a

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Side-effects of ivennectin............. ,........42Using a dental formula to determine a child's age.. ..................44Equipment needed for a field trip........ ........46Codes for countries, villages, ethnic groups .............48The DEC patch test......... ........49

. CHECKLISTS:. Preparing for a field trip.. ..........51. Upon arrival at a village........ ........52. Discussing problems with villagers. ............54. Setting up the facilities and organising the movement..............56. Census procedure: first visits.. .......58. Census procedure : later visits...... ......62. Preparing and applying DEC patches... ......64. Writing up the'Village Reporl'.......... .............61. Reading a DEC patch test...... ........12. Verification of new cases; the rnigration history .....74. Giving ivermectin during the visit. ..........75. Completing summary sheets of data collected ...............76. How to store and forward data after field visit. ........84

. CASE STUDTES. ..........85

Student assessntent. Assessment plarr.... .........88. Assessment form ..............90

PREFhCE

This module is intended for the following categories of worker:r Members of epidemiological surueillance teams who will be

conducting onchocerciasis surveillance in villages.r Supervisors of these teams (at zonal, regional or district level,

depending on the country).r Head office managers of onchocerciasis control in the country.

Trainers for this module should:r Have extensive field experience of all aspects of conducting

epidemiological surveillance for onchocerciasis control.I Have previous experience of conducting practical training courses.

Tlris rnodule is also suitable for in-service training. lrr such a case onlv tlrerelevant sessions are used.

The training of village level distributors, and general infonnation aboutonchocerciasis, are the subjects of other modules.

This manual has been prepared by Prof D Prozesky in collaboration with staff ofthe Planning, Evaluation and Transfer Unit of OCP - especially Dr B Boatin, Dr KSiamdvi, Dr W Soumbey Alley, Dr N Dembdld.Printing coordinated by Mr A Daribi

IF{TRODUCTIOI{ TO THE MODULE

In the past two decades onchocerciasis has been eliminated in West Africaas a disease of public health importance, and no longer constitutes anobstacle to economic development. This has been achieved at great effortand cost, and it is essential that the disease should not be allowed to retunr.The situation therefore has to be monitored continually.

The most important tool we have to monitor the situation is the so-called'epidemiological evaluntiott oJ'surveillnnce villoges'. Such villages havebeen carefully selected, so that if the infection starts being transmittedagain in an area we should find signs of such 'recrudescence' in theseparticular villages almost irnrnediately. Fonnerly this used to be done byexamining every person in the village over tlre age of one year, using aprocedure called 'skin snipping' - i.e. taking two small pieces of their skin,and examining these to see if there were any microfilariae of the parasiteOnchocerca volvulzs present in them. Every three years the same villagewas revisited, and the skin snips repeated.

The skin snip is an excellent test for surveillance, but it had certaindisadvantages:

' Villagers in surveillance villages were becoming reluctant to be'snipped' every three years. This is because it is a painful procedure,especially for children.

r The skin snip may fail to pick up cases where the number ofmicrofilariae in the skin is low (which is happening more and more,now that the disease is under control). In such cases the skin snip willfalsely be reported as negative.

For tlrese reasons a new test has been developed - the so called 'DEC patchtest'. 'DEC' stands for 'diethyl carbamazine', a drug which was formerlyused as a microfilaricide, but which has too many side effects and wastherefore discontinued. It is only applied to children from 5 to 20 years ofage. In this module learners are going to leam how to conduct'epidemiological surveillance' in a village, using DEC 'patches'.

The indicator used to establish a focus of possible recrudescence is thepresence of new infections. However any new infection should be carefullyinvestigated to establish if that infection has been acquired locally orelsewhere; and if elsewhere an effort should be made to localize as far aspossible the area wlrere the infection was acquired by carrying out amigration study. Only infections acquired locally suggest possiblerecrudescence, which is an indication for further investigation within thevillage and surror"rnding villages.

This module is designed so that it is both a tool for training, and a manualfor field workers to use in their day-to-day work afterwards.

In some situations the skin snip method is still being used forepidemiological surveillance. Its use during epidemiological surveillance isdealt with in a separate training module.

LEARNII{G OBJECTIVESEpidemiological surveillance is conducted by a team. For surveillancewhere DEC patches are used, each team has to perform two main tasks:taking a census; and preparing, applying and reading the DEC patch tests.Learners have to learn to perform both. The supe.uiro., of the teams alsoneed to learn them, so tlrat they can supervise the surveillance teameffectively.

At the end of the nndule ull trainees hnve to be nhle to perform tlrcfitllowing tnsks:I Prepare for the trip to the villages.. Approach a village for the first tirne.

' Approach a village for the second and susbequent times.

' Discuss the problems which the villagers have with the visit (andespecially with the examinations) with them,

r Set up the facilities for an epiderniological evaluation in a village.I Complete a 'Village repoft, (first visits only).r conduct a census of the village, using a standard form.r Detennine a child's age by using the 'dental formula'.I Attach a piece of adhesive tape to the left wrist of each person w6o is

to have a DEC patch test, and mark it with that person's opatch testnuntber'.

' Keep a notebook of census data corrections wlrich have to be made.I Prepate a 20Vo solution of DEC (diethyl carbamazine) in Nivea milk,and store it safely.

' Explain to villagers why the patches need to be applied.I Use the DEC solution to make a patch.

' Apply a patch securely to the skin over the left and right iliac crestareas of eligible villagers.

r Disctrss with each villager how to care for the patches during the 24hours that they have to remain applied.

r Read the result of the patch test after 24 hours.

r Record the findings in columns 38 and 41 0f the census form N602.

. Administer ivermectin correctly to persons fulfilling the necessary

criteria.. Analyse data collected at the end of each day, to identifu villagers who

may be classified as 'new infections'.

. Obtain a 'migration history' from each villager classified as a 'new

infection'.r Summarise the data collected in each village on three forms: 'Result of

the census'; 'Parasitological examination results'; and 'Summary ofnew cases'.

r Store all data sheets safely, making photocopies of them as soon as

possible and forwarding them without delay to the person wlro will do

the data entry into the comPuter.

At the end of tlte mhdule all trainees have to be nhle to:

r Describe how onchocerciasis is caused, and how it is controlled.. Discuss the reasons for doing epidemiological surveillance for

onchocerciasis in selected vi llages.

' List the equipment needed for a field trip.. Discuss important matters to consider when approaching a village for

epidemiological surveillance to be done there.r Describe the indications for giving ivermectin during epidemiological

surveillance visits, the contra-indications for giving it, and the dosage.

r List the equipment needed for perfonning DEC patch tests.

. Discuss how to store and forward data after a field trip.

PRACTICA L ARRANGEMEI\TS

Epidemiological surveillance is a skill - or more precisely, a group of skills.Learners learn skills by:

' Seeing them demonstrated by someone who is an expert.. Perfonning them themselves under supervision.I Cetting feedback on their perfonnance, so they can improve.

The ideal learning situation is therefore for learners to accompany anexisting epidemiological surveillance team when they go out on a field trip.The overall module timetable will therefore look like this:r Preparatory classroom work.r Field trip with existing epidmiological surveillance team.r Classroom work for debriefing and assessment.

The team of trainers should consist of at least one experienced census takerand one person experienced in preparing, applying and readirrg DEC skinpatches.

A detailed timetable is given in the next section. The programme is fivedays long, but another day or lnore may be needed to accommodate tirnefor travel to distant villages, larger villages which take longer to workthrough etc. The content of the module has to be covered, but trainersshould adapt the timetable according to tlre realities of their local situation.

Most surveillance villages have been used for a long tirne, and first visitswill therefore rarely be done. The practical training in this module willtherefore take place during a repeat visit to a village.

We assume that most of the learners are trained health workers, who havelearnt certain skills during their basic training, and practise themcontinually. It is therefore not necessary to include these skills in thiscourse. Examples:r Treating common ailments.

' Communicating health messages effectively.

The visit will take longer than usual, because in addition to the usual workthe leamers are observing, performing and being checked by tlreir trainers.A smallish village should therefore be chosen (not more tlran 200 persons).

In order not to disrupt the work of the team too much, the maximumnumber of leamers should be eight.

Learners must be warned in advance that they will be going out into the

field, so that they can bring along the necessary personal belongings, Even

if the village is close to the training centre it is better if the team sleeps out,

since that is what they will have to do in the field later. In any case theyhave to have time for the medical care of the villagers.

It is essential that the practical in the village should work well. The trainersmust therefore visit the village that is going to be used well in advance, tomake sure that the villagers are willing to cooperate. The date for the visitmust suit the villagers, and also fit in with the timetable for the trainingcourse. A few days before the course there should be a second visit, just tomake sure that the villagers are expecting the team.

In case the first village doesn't work out (e.g. because of an unexpectedevent like a funeral) it is as well to make affangements with a second

village, just in case.

The course is 5 days long and looks like this:r One day in classr Three days in the fieldI One day in class.

It is likely that the classroom training will be done at or near the districtheadquarters, so there should be a suitable village nearby. This shouldmake it possible to fit the training into the five days.

Amangements for transport and rneals for the field trip have to be made

well in advance. All the equipment that has to go with the team to the fieldhas to be checked, to see that it is working well. The supplies in the medicalkit must be checked. The medical kit may present a problem, in countrieswhere cost recovery is in operation. Whatever the team can get togetherwill be useful.

l0

There are plenty of materials to be prepared before the course starts:

. Teachers are advised to go through the plan for each session, where the

materials needed are clearly stated, and make sure they have everythingready that is needed.

. They need to get copies of handouts and checklists ready for eachlearner as well.

It may be that you have to train a group which is already familiar withepidemiological surveillance, using the skin snip method. In that case it isunnecessary to run this whole training course. Rather, you will select thesessions and handouts which deal specifically with the perforrnance of thenew DEC patch test:

I Especially Sessions 7a, 8, l0' Sr-nall portions of Sessions 5, 6, l1

It will be best to do this training in the field, but it need only last two days,

travellins included.

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DETAILE.D COURSE TTMETABLE

DAY 1

Morning: Classroom Session

Session I Introduction to the course

Time 07h00-07h50

Content . The objectives of the module.r Practicalarrangements.

Method r Introductions - trainers and learners introducethemselves to each other.Trainer introduces the objectives of the course. Time for leamers to ask questions, discuss,

clarif,'.Trainer hands out course timetable, goes through itwith learners.Trainer discusses practical arrangements withlearners: accommodation, transpoft etc.

Materials Handout:courseobjectives

12

Session 2 Onchocerciasis andsurveillance

epidemiological

Time 08h00-09h20

Content Onchocerciasis: how it is caused and spread.Onchocerciasis: symptoms and signs.The control of conchocerciasis and the success ofOCP.The role of epidemiological surveillance inpreventing the return of the disease.The end of OCP in 2002, and the need for countriesto take over the surveillance.

Method This sessions is best done as a discussion, since thelearners may know a lot already aboutonchocerciasis. Tlre trainer introduces each of thetopics above; asks what learners know; adds whatthey don't know.At the end lre asks: 'So what is epiderniologicalsurveillance? And why is it important ? And why doyou have to learn to do it?'

Materials Handout: 'Onchocerciasis(including if possible picturesskin and eye lesions caused).

and its management'of the parasite, blackfly,

l3

Session 3 Ivermectin; determining a child's age

Time 09h30-1 0h20

Content Ivermectin: indications, dosage, side-effects.Determining a child's age from his dentition.

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Method ' Discussion about ivennectin: its dosage, and thecontra-indications for its use. The trainer finds outwhat learners know and adds if necessary. Give outthe handout and discuss it.

' Similar disussion about the side-effects and tlreirtreatment - again giving out and discussing handoutat the end.

' Give out the handout about the dental formula.Discuss it until everyone is clear about what itmeans. Then call in the mothers with the smallchildren and use the formula to determine thechildren's ages.

NOTE: If the practical with children can't be organisedmake up a few case studies (see example at the endof the module).

Materials II

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Measuring rod.Ivermectin tablets.Handouts: 'Dental formula to determine a child'soge'; 'Giving ivermectin during the visit'; 'Side-effects of ivermectin' .

A few small children - ages 3 to 8 (of district teamstaff members if possible - with their mothers).

t4

Session 4 Approaching a village

Time 1 0h30- r 2h00

Content The irnportance of doing the visit well: building agood relationship.The information the village ueeds to have.Exactly what the villagers will be asked to do.

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Method Trainer asks: 'Why is it so important to have a goodrelationship with the villagers in the sentinelvillages? How can we build a good relationshipwith them?' Learners discuss, come up withsuggestions.Trainer gives handout: 'Upon arrival at a village' -all read the section 'Things to bear in mind' quietly,followed by a discussion of its main points.Group discussion about what to tell the villagersabout epidemiological surveillance - the key facts -trainer summarises on blackboard.Group discussion about what to ask villagers to doduring the visit - trainer summarises on blackboard.Learners work in groups of 2, read through thesecond part of the handout: 'Steps to follow'. Eachprepares a small memo that he can use during sucha meeting, on a srnall piece of paper.Role play: three learners play a team arriving at avillage, trainers and other learners play chief andvillagers (tlre learners use the memo tlrey haveprepared). After the play the 'team' get feedbackfrom the others, using the material in the handout asa checklist.Trainers asks a learner to summarise the lessonslearnt.

Materials II

Handout: 'Upon arrival at a village'Blackboard and chalk.

l5

Session 5 Problems villagers may have with theDEC patch test

Time 15h00-15h50

content . lll?"TJi:Fl.villagers

mav experience with the

Dealing with these problems constructively.

Method ' Trainer asks: 'How would you feel if a group ofpeople arrived in your village every few years andinterrupted your lives for two days?' Learnersdiscuss.Trainer asks: 'ls it important always to go back tothe same village? Why?' Leamers discuss thereasons.Trainer gives handout: 'Discussing problems withvillagers'. Learners work through it together.Role play. Three learners play the 'team', the

trainers and the other learners play a group ofdisgruntled villagers. The 'teaffi' tries the approachsuggested in the handout. At the end the others givefeedback.The trainers ask one of the learners to summarisethe lessons learnt.

Materials Handout: 'Discussing problems with villagers'

l6

Session 6 Preparing for the field trip

Time From 16h00 - as lons as is needed

content j Iffi :i'liH*: nTL::-H[T,HJ"l:lt:"0Preparing the census forms and the list of familiesto be examined.Preparing for the clinic for sick villagers.

Method . Learners are given the handout 'Preparing for afield trip' to read. The trainer discusses it withthem, and points out important practical aspects.Under guidance of the census clerk in the team thelearners prepare (by hand) all the census fonnsneeded for the coming visit. They complete thecolumns indicated in tlre handout: 'Censusprocedure: later visits'.When the forms are ready they are safely stored in afolder in the record box for that village.Everyone plans together how they will run the clinicfor sick villagers in the evenings.For the rest of the afternoon learners help the teamto prepare for tlre trip. They check all theequipment, using the checklists; also the box ofmedical supplies.The trainers (who are of course team rnembersthemselves) let the learners do as much as possiblethemselves, and guide them where necessary.The vehicles are checked and loaded.

Ma'feriars

: f,;;:Hru#ilf.l:Hi1;fl :;,. ff,'Preparing for a field trip'.

. Handout: oCensus procedure: later visits'.

. Handout: 'Preparing and applying DEC patches'.

T7

' All the equipment needed for the trip.

Session 6a In the evening

t Trainers meet to discuss the learners' progress thatduy.

' They make sure everything is ready for an earlystart the next mornins.

DAY 2

All day: Practical in the village

In the morning

The team travels to the village that is going to be

examined.

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Session 7 Arriving at the village

Time Sometime in the afternoon.

Content I

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Greeting the village leaders.Making practical al'rangements.Setting up camp.Preparing for the practicals the next day.

Method On arrival the trainers and leamers go to see thevillage chief and councillors, to greet them and tomake the necessary arrangements. The trainers letthe learners handle everything, and give feedbackafterwards.Using the box of past records of the village, thelearners prepare the list of families that must cornefor examination the next day, in the order that theyshould come (i.e. in the order of the 'Familynumbers'). They give the list to the person(councillor/ secretary) who is going to be arrangingthe arrival of the families for the examination thenext day.Tlre learners set up the camp and the working area,being guided by the handout 'setting up thefacilities and organising the movement'. Thetrainers superuise them.The learners also set up a place where they can seesick villasers.

Materials All the equipmentexamination.Handout: 'Setting upthe movement'.

for the camp and the

the facilities and organising

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Session 7a In the evening

' The learners have to familiarise themselves witlr theskills they are going to be learning the next day.Together with a trainer they work through thefollowing checklists:| 'Census procedure: first visits' and 'Census

procedure: later visits'.r 'The DEC patch test', 'Preparing and applying

DEC patches' and 'Reading a DEC patclr test'.

NOTE: This can be done in the aftemoon if the teamgets to the village on time.

r Group members with the necessary curative skillstake tums to see any sick villagers that arrive to be

examined and treated.r Finally trainers meet to rnake sure everything is

readv for the next dav.

20

DAY 3

All day: Practical in the village

Session I Conducting epidemiological surveillance

Time All day - w'ith breaks for tea and lunch.

Content Setting out the equipment.Conducting the census according to families.Noting changes from the previous census in thecensus notebook.Applying patch tests to everyone from 5 - 20 years.

Method r Learners set out the equipment under guidance ofthe trainers.The farnilies are called, as agreed, and the nonnalprocess of taking the census and applying the DECpatches starts. The trainers demonstrate first, thenlet the learners practice, and give feedback. Thismeans that every learner will have manyopportunties to practise the skills he needs to learn.Each learner must get sufficient opporturrity to learnboth tasks: taking the census, and preparing/applying the DEC patches. Here is an example of asuggested tirnetable, which will enable all learnersto learn eaclr skill well:

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. This is for 8 learners. If there are more or fewerlearners, this timetable can be adapted accordingly.

2l

lst period 2nd period 3rd period 4th periodtaking the census A,B,C,D E,F,G,H A,B,C,D E,F,G,Hpreparing and applyingDEC patches E,F,C,H A,B,C,D E,F,G,H A,B,COD

Materials II

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All the equipment that has been brought along.Handout: 'Equiprnent needed for a field trip'.Handout: 'Setting up the facilities and organisingthe movernent'.Handouts 'Census procedure: first visits'; oCensus

procedure: later visits'; 'The DEC patch test','Preparing and applying DEC patches'.

Session 9 Writing the oVillage Report'

Time 2Vrhours in the later afternoon/ early evening

Content ' The headings of the report.. Writing the repoft.

Method I

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Learners sit at the folding tables, in the shade.

Learners get a copy of the handout: 'Writing up the"Village Report"'. The trainer works through it withthem. They briefly look at the example in thehandor"rt.

Working in groups of 2 the learners write the reportfor tl-re village they are in, using the informationthey have gained during the visit. If they need anyadditional information they ask one of the villagerswho has been helping them.They first do a rough draft, then a neat one. Uponcompletion they hand them to the trainers whocheck them and give feedback (then or later).

Materials II

Handout: 'Writing up the "Village Report"'Paper and pens.

Session 9a In the evening

Learners with tlre necessary curative skills taketurns to see any sick villagers that arrive to beexamined and treated.It may be that villagers will arrive whose DECpatches fell off after less than 3 hours. They areirnmediately given new ones,, and instructed toreport towards midday on the next day for the test tobe read.Trainers meet to assess learners' skills, using theskills assessment sheet at the end of the module.Leamers who are still not coping are called in andan opportunity is made for them to practice againthe next day. This is unlikely, since the skills are notcomplex and there has been a lot of opporlunity topractise.

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I}AY 4

Morning: Practical in the village

Session 10 Reading the DEC patch tests at 24 hourslidentifying o new infections' ;ad ministering ivermectin

Time 3 lrours during the morning (24 hours after applying thepatches)

Content I

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Reading the DEC patch test.Identif,iing 'new infections' and taking a 'migratoryhistory' from them.Giving ivermectin appropriately to positive cases.

Method ' Begin 24 hours after the first DEC patches wereapplied.

' Demonstration by trainer, practice by learner,feedback from trainer.

' All the lean"rers get an opportunity to practicereading tlre patch tests, and recording the results.

' For every new case two learners work together totake a 'migration history' - all according to thehandout: 'Verification of new cases; the migrationhistory'. The trainers supervise.

NOTE: If there are no 'new infections', the trainers makeup one imaginary one for each learner. The learnerswrite down the 'migratory history'. Trainers checkthe work and give feedback afterwards.

' Positive cases are given ivermectin in the rightdoses (provided there are no contra-indications).

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Materiars . illliill;,+T,1*i.L?:r'":T'IJTJ;the migrationhistory'.Handouts: 'Giving ivermectin during the visit';' Side-effects of ivermectin'.

session 11 Writing the summary data tables

Time I % hours in the morning (after Session l0)

content : TffifflT:jllru'fr,:n:;The sumrnary of new cases.

Method . Learners sit at the folding tables, in the shade.Trainer gives out handout 'Completing summarysheets of data collected'.Learners work in groups of two. Each group getsgiven a copy of each summary form, and use theraw data to complete them. Tlrey refer to thehandout and are guided by the trainers.Trainers give feedback afterwards.

Materials . trtffi,.

'to-pleting summary sheets of data

The completed census fonns and migratory historiesfrom the previous day.Enor"rgh copies of each summary form.

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Session lla In the afternoon and evening

' The team works together to pack up the camp.

' Couftesy visit to chief and councillors to make areport, and to thank them. The learners undertakethis agairr, with feedback from the trainersafterwards.

r Return journey to the course base and classroom.

' Trainers meet :

. They go through Village Reports and assess

them.. They assess all the skills the learners learnt that

day, using the skills assessment sheet at the end

of the module.

26

DAY 5

Morning: Classroom session

In the morning

Trainers meet at 07h00 to set the questions for thewritten/ oral examination.

Session 12 Debriefing after the village visit

Time 08h00-08h50

Content Lessons learnt from the visit to the villase.

Method . Discussion. Both trainers and learners get theopportunity to raise problerns they had, or observed;solutions are worked out.This is also the opportunity for the trainers tocomment on any specific weaknesses they noted,and to reinforce important issues.

Materials The skills assessment sheet.

27

Session 13 Storing and distributing data

Time 09h00-09h50

content : i:".H?.1ffff,n'ii,1,,-o to be anarvsed.

Method ' Trainers give out lrandout 'How to store andforward data after field visit'. All work quicklythrough it.Learners decide what has to be done with the datanow; trainers give guidance. Photocopies are madeof every form that is to be sent off; the originals arestored in the box with the village data.If no photocopier is available, this will be done onreturn to Headquarters. Learners then discuss whatshould still be done.

Materials ' tu:$out: 'How to store and forward data after fieldvlslt'.Photocopier and paper (if available).

28

session 14 Choosing new sentinel villages

Time 10h00-10h50

Content ' The criteria for choosing sentinel villages.The process of choosing one.

Method r Trainer asks: 'Under what circumstances may wehave to choose new sentinel villases?' Discussionfollows.Trainer refers learners to criteria for sentinelvillages, at the back of the handout: 'Onchocerciasisand its management'. They work through it briefly.Trainer presents learners with a case study. Thelearners work through it two by two, and reporttheir decisions to the group. Decisions are discussedand feedback given.

Materials . Handout: 'Onchocerciasis and its management'.Case study on choosing a new sentinel village.

29

Session 15 Written test

Time 11h00-11h50

Content Questions covering all the knowledge and decisionslearners have to learn - dealing with 'rnust knows'ratherthan 'nice to knows'.

Method ' The trainers will have set the questions early thatmornlng.While the learners are writing the teachers meet tofinally assess all the leanters'practical skills, usingthe skills assessment sheet, and work out a totalmark. They decide who passes and fails thepractical.The trainers do the marking during the lunch break,and prepare the sheet with the final results.

Materiars : i[#:;":.:::,--

Afternoon : Short classroom session

Session 16 Closing ceremony

Time 14h00- 14h20

Method ' The results are put up oll a notice board before the

ceremony.

' The usual: thank yous, handing out of attendance

certificates and enjoying a snack.

30

OI{CHOCERCIASIS AI{D ITS MAI\AGEMENT

onchocerciasis is a disease caused by the macrofilaria onchocercavolvulus, which invades the subcutaneous tissues of the body.

The Iife cycle of Onchocercfl volvulus

Within ayear the f'emale worm startsproducing millions of microfllariae, r+'hichmigrate to the skin of the infected person.The adult worms live for about 15 vears.

When the blackfly bites a human again,the larvae are introduced into the skin ofthis individual. The larvae grow intoadulthood in the subcutaneous tissues ofthe new victim.

The female blackfly Simulittm needsblood meals befbre she can lay hereggs. When she bites an infectedperson she ingests some of themicrofilariae together with the blood.

The microfilariae go through three larvalstages in the blackfly. The last one migratesto the head and mouthpiece of the fly.

The life cycle of the blacklly Simulium

After taking a blood meal the fbmale backfly lays hereggs at the edge of fast flowing streams and rivers.

After going through a fewlarval stages and a pupalstage, the adult flies emergefrom the water 7- l0 days afterthe eggs were laid.

The eggs hatch and the larvae live inthe rvater. attached to objects likeleaves. sticks and stones. They needoxygen rich rvater to thrive. which iswhy the fly lays her eggs nexr to f-ast

flowing water.

A blackllySinmliunttaking its

[rloocl nreal

liggs of thcblackllySintuIiturt

attachcd to astick

The adult female fly lays a large number of eggs every 4 to 5 days ofher short life. Between every egg laying she has to take a blood meal.

She will therefore bite several lrumans, at an interval of a week or so.

This makes her an ideal vector for the parasite.32

' The blackflies clearly prefer living close to rivers, and that is wheremost cases of onchocerciasis are found (hence the old name 'riverblindness'). However a single fly can migrate a hundred kilometres orfirore, especially if assisted by strong winds.

Symptoms and signs of onchocerciasisAlmost all the symptoms and signs are caused by the microfilariae, and notby the adult worm.

' Tlre most comnton symptom is itcltirtg, which is caused by body'sreaction to microfilariae dyirrg in the skin. It is severe and continuesday and night. This leads to the following clinical signs:

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An onchocercal dermstitis - small papules.

'Lizard skin' - areas of roughening.'Leopard skin' - areas of depigmentation (especially on the lowerlirnbs).

As the number of rnicrofilariae in the body increases, increasingnumbers find their way to the eyes. Every part of the eye is everltuallyaffected by inflarnmation, tissue damage and scarring. This leads to agradual loss of vision, and eventually to irreversible blindness - oftenby as early as the age of thirty-five.

The adult wonns may cause painless nodules under tlre skin. These areespecially noticeable over bony parts like the skull and pelvis.

The constant itch (leading to lack of sleep), the slow loss of vision, andthe effect of the high parasite load together have a profound effect onthe quality tf life of the sufferers. They become weak, debilitated anddepressed. In small children tlre heavy parasite load can interfere withgrowth and development, leading to a clinical syndrome refered to as

' onchocercal cretinism' .

As a result of the disease many fertile river basins were abandoned bytheir populations, with profound economic consequences for the countriesconcerned.

JJ

Symptoms and signs of onchocerciasis

Itching Onchocercal dermatitis 'Lizard skin'

'Leopard skin' Nodule on the face Loss of vision

Diagnosis of onchocerciasisThe diagnosis is made by taking two small skin biopsies (over the left andright iliac crests respectively) and examining them microscopically. Theliving microfilariae are easily observed emerging from the biopsies.Alternatively the 'DEC patch' method may be used - more about this later.

34

C OT{TROL OF ONCHOCE.RCIASIS

ln order to control the disease we have to break its cycle of transmission(man + blackfly + man). There are two ways of achieving this:

L LarvicidingThe goal here is to eliminate the vector Simulium by killing its larvae:

. Each river where it breeds has to be identified, and an insecticideadministered to each breeding site in those rivers once a week.

' This has mostly been done by helicopter, but also on the ground andwith boats.

' The process has to be continued for atworms have died out and there are nopopulation.

least l5 years, until all the adultrnicrofilariae left in skins of the

Larviciding bl' hcl icoptcr

JI

Crouncl larviciciirrg

Larvic:idinu bv boal

38

2. Community directed trestment witlt ivermectin (CDff)Ivermectin is administered to the whole population of the affected areas

once a year (sometimes twice):

Such infrequent administration is sufficient since all microfilariae are

killed, and the feftility of the female worm is dminished for a

susbstantial period.

As a result transmission of the parasite is cut down by 7 5Yo (but nothalted completely).

The administration is achieved done by enlisting the help of thevillagers themselves.

Even those who feel well must be treated, since althouglr their parasite

load may be low they can still be sources of infection for others.

Larviciding is the most reliable and effective wny of eliminating tltedisease. CDTI helps the larviciding to take effect more quickly, but is notsufficient in itself to achieve control where there is a high prevalence oftlre disease. In situations where the parasite load is low CDTI willprobably be sufficient to control the disease, but it will have to continueyearly for many years.

39

Since 1974 the Onchocerciasis Control Programme (OCP) has been usingthese strategies to control the disease in West Africa - first only larviciding,then later CDTI as well. We now have a situation where the disease is nolonger a public health threat. In addition, many thousands of hectares offertile land in river basins have been resettled.

The role of epidemiological surveillanceIt is very important to know whether the control measures are working. Oneof the ways in which this has been done is by active epidemiologicalsurveillance - going out into the community to find out whether the parasiteis still there. OCP has selected specific villages in each river basin that wasaffected by the disease. The population in thern is followed up every threeyears, to see what is happening to their parasite load. This may be done irrtwo different ways:

' By examining the biopsies described above for every person over theage of one in the village.

' By performing the DEC skin test on all persons form 5 to 20 years ofage in the village.

In both cases this is done to see how many are still carrying the parasite.

It is essential to use the same village every time. For example:

In 1998 Village A has l2 people with positive tests, and Village B hasonly 5. So we would think that the situation is worse in Village A.However we know that in 1995 Village A had 23 positives, whileVillage B had only 2. This rneans in fact that Village A is improvingnicely, but Village l3 is having a problem! There may be a problem inthat river basin. We only know this becaase bte examined both of thevillages before.

Up to now OCP has been organising the examination of these 'sentinelvillages' every three years. However OCP is coming to an end in tlre year2002, and the healtlt services of the II coantries where it operates willhnve to take over this nctivity of 'epidemiological surveillnnce'. Only thencan we be sure the disease is detected early if it returns, which makes itpossible to control it with CDTI.

40

Criteria for selecting villages for epidemiological surveillanceThrough the years OCP has developed strict criteria for selecting villageswhich are suitable as 'sentinel villages':r They must have had a high level of onchocercal infection in the past.r They must be near a major blackfly breeding site.

They must be 'in the first line' - that is, there 'ray

not be any othervillages between them and the breeding site on the river.They must not be too big - the population shourd be frorn 200 to 300.They must have a stable population- there must not be a lot ofmigration in and out of the villaee.

It is important to know about tlrese criteria. Although the 1l countries willcontinue to use the sentinel villages that OCP identified, they may have toselect more as time goes on.

t

I

41

SIDE-EFFECTS OF IVERMECTII{

These are usualty mild, and are mostly caused by the reaction of the body

to rnillions of dead microfilariae - a sign therefore that the treatment ltas

worked. Interestingly community members spontaneously have this

perception too. In most cases the side-effects appear within 24 hours of the

ivennectin being given, and clear up spontaneously, without further

treatment, within a day or two. The most common side-effects are:

Itching. This can be very harsh but only lasts for a few days.r It is considered severe if it stops the person from working or sleeping.

It should tlren be treated with an antihistamine.

Oedema. Tlris is sometimes generalised but is usually localised in some part of

the body - often the face, often like a nodule. It disappears a few days

later.r It is considered severe if it intertbres witlt normal movenrent of the

affected parL Aspirin should be given.

Fever

' This is usually mild and of short duration.r It is considered severe if it lasts longer than a day. In that case the

patient shogld be investigated fufther, and the real cause (e.g. malaria)

should be treated.

Pain. This can be located in any part on the body, ffi&Y be localised in the

swollen parts, may involve the joints, or take the form of a headache.r lf it is severe it should be treated with aspirin.

Dizziness or syncoper This coffres on fairly quickly after taking the ivermectin. The patient

should be encouraged to rest, and to take extra fluids-

42

I)iarrhoea

' This is a very rare complaint.r If it is severe it should be treated with the usual rehvdration solution.

All severe reactions must, if possible, be seen by a doctor or nurse at ahealth centre. There is a specific form that has to be completed in such acase. This form will be passed on to the manufacturers of Mectizan@ fortheir records.

43

USING A DE]\TAL FORMULA TO T}ETERMIF{E ACHILD'S AGE

I Numbers above the line refer to teetl-r in the top jaw, those below the

line to teeth in the bottom ja*.I The Roman numbers indicate milk teeth, the Arabic numbers indicate

adult teeth.. The ase estimations are accurate within 2 months for rnilk teeth arrd I

Milk dentition Adult dentition

6-8 months

8-10 months

12 months

14 months

16 months(first molar)

l8 months(canine)

20-30 months(second molar)

II

I

1.il

t.tII.II

I.II.III.IV

r.il.ilI.ru.v

1.2.III.IV.V.6

6 years

7 years

8 years

9 years

10 years

L1 years

12 years

I.II.III.IV.V.6I.II.III.IV.V.6

I.II.III.IV.V.61.[.tII.IV.V.6

2.rrr.4.v.6

2.3.4.V .6

2.3 .4.5.6

2.3.4.5.6.7

year for adult teeth.

Estinratio'of a child's age usine the dental fbr'rLrla

45

EQUIPMEI{T I{EEDED FOR A FIELI} TRTP

The following equipment needs to be taken on a field trip:

For the censusr d folding table and chair.r f, pencil.. Enough census forms (pre-prepared, in the case of repeat visits).. Copies of all the past records for that village, in their box'

For the isolation tent (where the patches are applied and read)

I d piece of canvas, poles, ropes and tent pegs to rig up the tent.r I folding table and chair.. All the equipment for preparing and applying the patches (see handout:

'Preparing and applying DEC patches').

For the ivermectin treatment pointr fi folding table and chair.r I supply of 1000 ivermectin tablets.

For personal needst For each team member:

t a stretcher or foam mattress

. beddingI a mosquito net and/ or tents for sleepingr a set of eating utensilsI personal bag with clothes' toiletries etc.

r For the team:r a 50 litre water container, fullr a paraffin stove (two burners)| 3 paraffin lamps and l0 litres of paraffin. cooking pots,, pans, knives, spoons

r bowls for washing upr washing up liquid.

46

For the vehicleI An extra spare tyre.r I jack and wheel spanner.r Basic tools for the vel-ricle.t 25litres of petrol.I ,{ litre of engine oil.

A basic pharmacy/ first aid kitEvery team will have to see wl-rat it can get together by way of rnedicalsupplies. In countries where cost recovery is in operation it may not bepossible to get any rnedicines at all. Here is a list of what would be useful -but anytlring is better tlran nothing:. Aspirin (tablets)r Paracetamol (tablets and syrup)

' Chloroquin (tablets)

' Penicillin VK (tablets and syrup)r { broad spectrum antibiotic like co-trimoxazole or ampicillin (capsules

and syrup)r Metronidazole(tablets)I Tetracycline(capsules)I A bottle of antiseptic solution (e.g. chlorhexidine)r Antiseptic creaffr (e.g. povidone iodine)r d fungicide cream (e.g. Whitfield's ointment)r fi thiazide diuretic (tablets)r Aminophylline (suppositories and tablets)

' Bandagesr Gauze and cotton wool swabs. Sticking plaster.

47

CODES FOR COUNTRIES, VILLAGES,ETHNIC GROUPS

Country codes

I I Burkina Faso

2 | Mali3 | C6te d'Ivorre4 | Ghana5 | Togo6 | Benin7 | Niger8 | Guinea9 | Senegal10 | Guinea-Bissau1l I Sierra Leone

Codes for ethnic groups and villages

These are specific for every country. The national onchocerciasiscoordinator will supply them to the team at the time of training.

48

THE DEC PATCH TEST

The way it worksDiethyl carbamazine (DEC) is a microfilaricide drug. It is still beilg used(given by mouth) to treat some filarial diaseases, and was fonnerly used totreat onchocerciasis. Its use in onchocerciasis was discontinued because itcaused a severe inflammatory reaction around the microfilariae that werebeing killed - the so-called Mazotti reaction:r In the skin this caused intolerable itching for a few days.r Ocular lesions often became much worse, even leading to blindness. It

was this complication that led to the decision to stop using it.

DEC therefore causes a strong inflammatory reaction when it comes intocontact with tlre microfilariae of Onchocerca volvulus. It is thischaracterisitic of the drug that forms the basis of the DEC patch test:. The DEC is mixed with a neutral cream

rectangle of filter paper.(Nivea milk) and applied to a

' When this filter paper is applied to the skin, the DEC is absorbedlocally.

NOTE : A commercial 'patch test' is being developed and will be availableshortly.

r If there are any microfilariae of O. volvulus in the skin nearby, aninflammatory reaction will commence within 3 hours. This can easilvbe seen with the naked eye after 24 hours.

Advantages of the test

' The great advantage is that, unlike the skin snip, it is 1ot painful.Villagers are therefore less likely to object to the test being peifonnedon them repeatedly.

I Another advantage is that it is more sensitive than the skin snip. Incases where there are few microfilariae left in the skin, the patch test ismore likely to show them than the skin snip.

49

lt is easier to perform and to read thanapplied by staff after simple training.

the skin snip. It can therefore be

Inflartrnratory reaction caused by DEC

Disadvantages of the patch test. Although not painful, positive tests are sometimes itchy, which may be

troublesome especially for small children.

r One has to wait 24 hours before reading the test

which can be examined immediately).r The patches can coffIe unstuck during the 24 hours

to the skin.r If a person is infected with the parasite Mansonella streptocerca the

test is also positive - in other words, afalse positive.

(unlike the skin snip

that they are applied

50

PREPARING FOR A FIELD TRIP

In preparing the plarr for a sirnple evaluation round, the team leader shouldbear the following points in mind:1. Check with the national oncho co-ordinator if and when ivennectin has

been distributed in the villages concerned. It is no use doingepiderniological evaluation if ivennectin has been recently given out.

2. Evaluations must be conducted during the dry season. In the rainyseason farmers are busy in the fields and only a few people would beavailable for examination. Moreover, some villages aie inaccessible atthat time of the year. Avoid the Ramadan period and importantfestivities of the area.

3. To ensure maximum collaboration by the population, village authoritiesshould be informed of the impending evaluation and if possible of theprecise date of the team's arrival.

4. The team slrould arrive irr each village during the aften.loon of the daypreceding the evaluation in order to mobilize the population.

5. Even an experienced team cannot examine more tharr 300 people in aday.

6. A pattern of one day's travel alternating with one day of evaluation isideal unless the evaluation of one or more villages with populations ofover 300 is planned. A longer time will have to be spent i1 such avillage.

7- Information should be collected on the accessibility of roads a'd tracksso that travel times can be calculated realistically.

8. In case of a follow-up evaluation, a list of all people examined duringthe baseline survey should be taken to the field, plus ALL theirprevious results. This is absolutely essential if new cases are to beindentified.

5l

UPON ARRTVALAT A VILLAGE

Things to bear in mind

' Villages are being asked to help with the surveillance voluntarily - they

cannot be forced. The team members therefore have to be very polite

and respectful throughout.

' Village authority structures are different :

Some are lnore autocratic, with the chief in council rnaking

decisions on behalf of the village. In such a case the team willexpect decisions to come from the chief.

Some are more democrstic, with decisiols being made by

discussion and eventual consensus in a .meeting

In some tlrere is a conflict of leadership, in which case the team

faces a difficult situation. If there are porblems in such villages(for instance, a reluctance to cooperate) it is probably best to tryfor a meeting with many villagers present, as a forum to explain

the programme again and ask for help.

Team members have to draw on their knowledge of the local

community to decide which approach to use-

r The team has to work tl-rrough the village authorities (chief, council).

However the cooperation of the whole village is going to be needed.

Therefore the team should use each opportunity to reach out to the

villagers, explaining the programme and motivating them to take part'

' The curative service offered by the team to sick people in the village

during the visit is very imPortant:

r It helps those in need.r It builds confidence in the team-r It improves cooperation : villagers feel they are not just being used.

Steps to followl. As soon as the team arrives in a village, the Chief and the Secretary of

the village should be contacted, together with any other persons of note

(e.g. trainer or health assistant) who are present. Explain to them:

52

r The purpose of the evaluation - they may be clear about thatalready, but it is worth making sure.

r That the team will try to treat the sick. A time and place forconsultations must be agreed upon - for example, at the team,scamp on both evenings while the team is in the village.

2. In most villages the key person wilt be the secretary, whoseresponsibility it will be to inform lreads of families of the impendingexamination and arrange for them to be present the following mornin!with all the members of their farnilies.

3. Prepare a list of the families to be examined:r In the case of a follow-up evaluation the list will be available from

the previous survey forms.

' [f the village is being evaluated for tlre first tirne (which isunlikely), collect information on the number of families, their sizeand duration of their residence in the village frorn the Secretary.

4' Give the list of farnilies to be examined to the Secretary. Ask him tocontact the heads of farnilies included in the list, and io u.ru,lge forthem to be present the following day early in the morning (latest by7.00 a.m.) at the survey site, with all rnembers of their family.

5. If the village is too large for the survey to be completed in o1e day,nrake sure that tlre families convened for the first morning do not totalmore than 300 individuals, leaving the rest to examine the dav after.

NOTE:

' For epidemiological surveillance, it is necessary to follow up the same villagefor a long time.

' The whole population in the village must be examined, and it is essential toimpress that fact upon everyone - the team's census clerks, the village Chiefand Secretary, and the heads of families.

' If the percentage of non-attendance is too high, the data collected will bemeaningless.

' An additional effort should be made to examine atl individuals of the villagewho were examined during the baseline (meaning the first ever) survey.

' In view of the fact the procedure is a nuisance, the reasons for comingback tothem every 3 years must be discussed frankly and openly.

53

DISCUSSING PROBLEMS WITH VTLLAGERS

The DEC patch test is not painful, but it can be rather itchy and villagers

may regard it as an unnecessary nuisance. Small children especially rnay

,-,oi like it. On the other hand it is essential for surveillance ofonchocerciasis that the same village must be examined repeatedly, so that

new cases can be picked up as soon as possible.

If the team finds that they are not entirely welcome in a village, they willhave to enter into dialogue with the villagers. The unhappiness will usually

be verbalised by the rhi*f of the village, when the team goes to visit him

upon arrival:. First of all the problem has to be discussed with the chief - to find out

what his objections are. His objections must be taken seriously, and

every effort taken to persuade him that his fears are groundless, and

that the testing can only be of benefit to hirn and his village.

r If it is clear that some villagers are not going to cooperate, the team

should ask potitely if as many villagers as possible can be called to a

meeting, so that they can explain the reason for the examination again,

and perhaps persuade villagers to take part after all. This is important,

since it is part of the process to give ownership of the programme to the

village,which is going to be necessary to legitimise the programme in

the village.

Once the villagers are assembled, the team gives first opportunity to the

villagers to voice their complaints and objections:

. The villagers must be given enough time to say everything they want to

say, without interruPtion.

r The team members have to take everything that is said seriously, and

not minimise it. However if the villagers have any misconceptions, the

ream can politely state the true facts as they know them.

Once the villagers have had their say, the team explairrs carefully why they

always come back to the same village:

54

This village was chosen because there used to be such a lot ofonchocerciasis sufferers in it. So if the disease comes back, if there are

new cases, this is where we are going to find it quickly.

If we take another village now and find people with onchocerciasisthere, we won't know whether they are old or new cases (remember the

adult worm continues to live and produce babies for 12 years).

lf we find itquickly it's easyto stop it- butonce ithas gonetoo far it'svery hard. You can share with thern a saying frorn Togo: 'lf you wantto kill a snake you have to cut off its lread' - so if we want to kill thesnake of onchocerciasis we have to do this monitoring of villagesthoroughly. Imagine how awful it would he if the disease comes back,and we find out too late to stop it.

You use this kind of reasoning to try to persuade the villagers. Do not try tothreaten or force them - they are not obliged to help you at all, and youwant them to continue helping in the years to come.

55

SETTII{G UP THE FACILITIES AI\D ORGAI\ISIT\GTHE MOVEMENT

Use a shady outdoor area (e.g. under trees), or the school buildirrg, or acombination of both. You lrave to set up three 'stations', like this:

Families will be called one at a time, but some may contain a large numberof people, so leave sufficient space between the different posts to avoidovercrowding.

56

census takenstart (dayl & 2) finish (day 1)

WWWMv"

patch appliedpatch read

t:W,,finish (day 2)

Iwwwsxffiw

$

Staff member

Movement of villagers

Movement of forms

ivermectingiven

The familiesOn the Jirst dny:r The census clerk asks the family to approach. As soon as each family

member is wriffen up, those that will get the patch (everybody over 3

years of age) gets a piece of sticking plaster with their patch numberstuck on their left wrist.

' Then they go one by one to the isolation tent for their patch (except thechildren under one year).

On the second duy:r The census clerk asks the family to approach. He checks the name and

patch number of each person.

' Then they go one by one to the isolation tent for their patch to be read.

. Then they go to the ivermectin table, with the census form. Thepositive ones get the right number of tablets (unless tlrey have a reasonfor not getting treated). Note that the ivermectin table is manned bywhichever team member is free.

r Then the whole family can go home.

The census formsOn thefirst day:r The census clerk fills them in first, and sends them to the person

applying the patclr.

On the second clay:r The census clerk checks tlrem, and sends them to the person applying

the patch.

r The person applying the patch fills in the test results, and sends them tothe ivermectin table.

r At the ivermectin table the number of tablets siven is filled in. and theforms are sent back to the census clerk.

57

CEII{SUS PROCEI}URE:

The first taskbroken down

in any village is to conduct ainto residents present, residents

First visit: procedure

' The equipment required consists of: apens, and a supply of N602 census foattached to this lrandout.

NOTE: An interpreter, preferably native tothe census officer cope with lanindigenous from non-indigenous

All families that reside in the village a

each farnily is included: those that are(short or lorrg term); and children under INOTE: If the trend of onchocerciasis incide

population studied must betemporarily in the village must'visitors','nomads','government

Each family unit is allocated a separateif the number of familv members exceed

After you have entered all the particus/he passes to the isolation tent, put on hplaster marked with her/ his patch test nu

First visit: fiIling in the c€nsus form (NFirst identify the data sheet by filling in the

' 5-8 Date of survey.

' 9-I0 Passage number.

' II-12 State - code number.

' 13-16 Village - code number.t l7-18 Section - only complete if a villa

58

IRST VISITS

nsus of the entire population,absent and non-residents.

ble, a chair, some ball-points. A copy of such a fonn is

e village, will be needed to helpge problems and distinguish

included. Each member ofresent; those that are a way

year.

is to be properly reflected, thele. Therefore persons onlyincluded and noted as such:

icials' and so on.

rrn or 'data sheet' (or fonns"the spaces on one form).

for an individual, and befores left wrist a piece of stickingber.

)xes at the top:

has more than one section.

!9-21_ Family number - given by the census clerk at the first visit.Each family has a separate sheet (or two, if it is very rarge).22-24 Ethnic group - using the ocp/Epl list of ethnic codes.

The body of the form consists of l4 columns,t First colamn The patch test number _

individuals who qualify for, and agreeallocated by the census clerk.

' second column The serial/ order number - 1,2,3, 4 etc. (for eachindividual in the village - those who get examined and those who donot)' This is allocated by the census clerk, as the people are entered onthe list.

' Tltird column Name of the person.r [n the first line write the name of the head of the flamily; in the

'extthat of the first wife, followed by those of her children in order ofdecreasing age; then those of theiecond wife and her children, etc.

' All persons sharing the household's dairy meal (e.g. nephew,grandchild, widow) are considered to be members of the-farniry.r Family relationships are indicated by a code written immediatelyafter the person's name. Adults are identified by their positionwithin the family, and children by reference to thelr parents. Thefollowing key is used:

HF : Head of family

Wi : Wife

Ch : Son or daughter

Sib : Brother or sister

FR _ Cousin

EN : Nephew, niece, grandson or granddaughter

W : Widow or widower

Pa : Father or mother

to be completed as follows:7,2, 3,4 etc. (only for thoseto, the examination). This is

59

. Some examples:

Coulibaly Omer HFOUA|fiATA ZenAbOU WiI (meaning: 'the wife of l')

Coulibaly DdSird ChIxZ (meaning: 'the child of I and2')

Traord Bernard FRI (meaning: 'cousin of 1')

ZS-j/L Individual number - the individual number is assigned later on

at the office to enable the data to be processed by computer.

3l Sex - assign code 1 for male and 2 for female' A person's name

does not necessarily reveal his or her sex' and errors are frequently

made in this regard. Always ask whether a child is a boy or a girl'

32-33 Age:r If a birth certificate or identity paper is available, record the age the

person or familY gives You.. if not, estimate by reference to a person of the same generation

who does have one. Otherwise ask the person his age and take the

average between his reply and the census taker's guess.

. Children's ages are determined by the dental formula (see handout)'

34 Already registered - the coding is as follows:

NOTE: lf this is a first passage, codes 1, 2 and 3 will not be used.

60

0 never.registered before"(first survey in the village

already registered in the village

born since the last survey

born before the last survey

I2

I4

: Ji Exam.status - the coding is as follows:

1 present during the visit and examined

2 present but refused examination

3 present but not examined (because of old age, illness,pressure of work, etc.)

4 absent from tlre village for less than a year

5 changed residence to another village

6 Deceased

7 absent from the village for more than a year

NOTE: Codes 5 and 6 will be used only on second andsubsequent passages.

' 36-41 Patch test readiog - reading after 24 hours. Write the left sidereading in column 38, the right side in column 41.

' 42 Leave blank.

' 43 Height. 44 lvermectin dose.These columns are completed only when ivermectin is indicated andhas been given after microscopy.

' Last column - observations. Specific mention should be made, inparticular, of:I The whereabouts, if known, of anyone who is temporarily absent or

has Ieft the village for good - write name of present residence.r Migrants who have come into the village - write 'recent

immigrant'.. Any person who did not present him/herself for examination but

resides in the village and is known to be blind - write oabsent-

blind'.. Skin rashes present at the time when the patches are applied.

6l

CEI\SUS PROCEDURE: LATER VISITS

Preparation in the officeThe census officer's work begins in the office with the preparation ofupdated forms (N602) to take to the field:r You prepare the forms by filling in the pafticulars of all the persons

whose 'Examination status' at the previous visit was 1,2,3 or 4.

' Start by copying from the previous visit's forms the data in the :

r Third colamn Name of person.r Fourth column : 25-30 Individual number.. F{th colamn: 31 Sex.

' Sixth column: 32-33 Age - increase the ages by the time that has

elapsed since the previous visit.

' Seventh column : 34 Already registered - write the code '1' for allpersons listed.

NOTE:r The patch test numbers will not be assigned until the examination takes place.r For the old villages surveyed before by OCP a computer programrne called

SEPT can be used to prepare do this preparation automatically.I The prepared forms are carefully stored in a file/ jacket, which will be taken to

the field. Indicate on the jacket the scheduled date of the visit andthe passagenumber (second, third, etc.).

In the fieldI On a second passage, new registrations will include:

. Children born since the first passage.r Women newly married into a family and coming from another

village.. Any family members overlooked ou the first visit.These persons are written down on a new line at the bottom of thefamily sheet of tlre farnily tlrey now belong to.

62

Seventh colamn: -34 Already registered - newly registered personsmust be coded 2, 3, or 4 in the to distinguish them from those alreadyregistered on the first visit.

Eigth column: Ji Exam.status - codes 5 and 6 are used foreliminating from the sample persons who have left the village or havedied since the previous visit.NOTE: Often a person coded 5 on the previous visit reappears in the village.

In that case the earlier file should be corrected, code 5 being replacedby 4 or 7 depending on the length of the absence.

Any correction needed to the data recorded on the previous passagemust be made in the field, and then brought to the attention of thoseresponsible for the data processing. For this it is essential that thecensus officer keep a notebook in which all such corrections arerecorded. Examples:

fndividuat no. 138432 - Sex I on Page Ifndividual no. 138720 - Age 4 insfead of g on Page 3fndividual no. 13900? - Exam.sfafus 7 insfead of 5 on Page Z

When an individual changes family (moving for example from Family4 to Family 12):r Enter all his particulars on the data sheet for Family l2 and cross

them out under Family 4.r Note tlre change in the respective Observations columns:

Transferced fron F/4 and Transferredto F/12

After you have entered all the particulars for an individual, and beforehe/she passes to the isolation terrt, put on his/her left wrist a piece ofsticking plaster marked with his/her patch test number.

63

PREPARING AND APPLYING DEC PATCHES

Preparing the 20"h DEC solution

You need the followingequipment:

' Nivea milk.r Diethyl carbamazine (DEC) in powder form.r I chemical balance.r A. measuring cylinder.r I one litre plastic or glass storage bottle (with a tight fitting lid).

The fol lowing procedure is followed:. Using the measuring cylinder, measure out 500 ml of the Nivea milk

and pour it into a beaker.

r With the chemical balance weigh out exactly 100 g of DEC powder(crystals). Add these to the Nivea milk in the beaker.

I Mix until all tlre DEC has dissolved:t You can use a laboratory rotator if you have oner Otherwise you mix by shaking the beaker gently by hand.

r Pour the resulting rnixture into the bottle, and close the lid firmly.. Write the date of preparation on a piece of sticking plaster, and stick it

onto the bottle:r If the solution is stored at room temperature in the shade it will last

for 6 months.. If it is kept in the main compaftment of a refrigerator it will last as

long as a year.

Preparing the DEC patch

You need the following equipment:r The 20% DEC solution.I d few sheets of Wattrnan no. I filter paper.r d pencil and ruler.. Scissors (suitable for paper and cloth).

r Forceps.r several rolls of zinc oxide sticking praster, width 50 ffiffi, with

perforations (the perforations are essential in hot climates, to allow theskin to breathe and remain drv).r ,{ small bowl.

You can do the following in advance:r Mark out rectangles of 2 cm by 3 cm on the filter paper.r Carefully cut out tlre rectangles.r Also cut a few rectangles of zinc oxide sticking plaster, about 50 mm x

100 rnm. Place them on a flat surface with the sticky side up.However the next steps are perfonned immeiiately before applying thepatches:

' Slrake the DEC solution well. Pour about 50 rnl into the small bowl.r Take a rectangle of filter paper with the forceps, and dip it into theDEC mixture. wipe off the excess on the rim of the bowl.r Place the wet paper in the rniddle of one of the pieces of stickingplaster that you have prepared. Together the sticking plaster and thepaper fonn the patch.

Applying the DEC patches

You need the following eguipment:r The prepared DEC patches.r Cotton wool swabs.r 80% alcohol solution.

Here is the procedure you follow:r The patches are only applied to persons from 5 to 20 years of age.

NOTE : It is likely that younger children will also be tested in the near future.I Prepare two patches for each person, just as s/he arrives.r comrnunicate with each person throughout the process:

r Greet him/ her in a friendly way. If it is a small child, greetthe mother or father as well.

I Ask if s/he (or his/ her parent) knows what is going to happen. Ifs/he does not know, explain carefully:

65

't The aim of the test is to find out if people have the onchocerciasis

parasite.* -Explain

the procedure briefly. It is painless, but the patches rnight

start being a bit itchy after a few hours.

'. Explain that s/he must try very hard to keep the patches from falling

off until s/he sees you again after 24 hours. For example, s/he must

try not to fasten a belt or girdle over the place where the patches are

applied, since this will spoil them.

'? After 24 hours s/he rnust return to you for the test to be read.

. Explain that if s/he is found to have the parasite, s/he will be

treated immediatelY.I Ask hirn/ her to come back if the patch falls off within 3 hours.

r Thank hirn/ her for participating.

Ensure each person's privacy - remember, you are asking them to

expose themselves. Small children won't mind, but teenagers might.

Clean the skin over the middle of both iliac crests with cotton wool

soaked i1 alcohol, so that the sticking plaster sticks well. Wait for the

skin to dry.

Carefully examine the skir-r where you are planning to apply the patch.

If there is any lesion or rash, try to move the place where you plan to

apply the patch a little to one side (but still on the iliac crest).

If you cannot avoid the rash, or if the person has a generalised rash,

*uk" a note of it under the column 'Obsentations' on the census form

N602, as follows:t 'Local rash' : rash on iliac crests, on site of patch test

. 'Body rnsh': gefl€ralised rash on other parts of the body

In such a case you apply the patch anlrway. When you read it 24 hours

later, you take the existing rash into account.

Apply a patch in the middle of the area you have just cleaned and

examined:I Place the long axis of the patch along the iliac crest, not across it.

I Try to avoid the place where the person seems to place hisi her belt

or girdle.o Rub the sticking plaster thoroughly to make sure it sticks well-

Repeat the same for the other iliac crest.

66

WRITII\G UP THE 'VILLAGE REPORT,

Note that this is only done at the very first visit to a village.

To facilitate the completion of the'Village Report', the headings are listedbelow, and information given about the expected content under eachlreading. Please treat them in the order indicated below so as to standardisethe presentation of the forms. Each form should be signed by its author(s).

At the top left hand:r Name of state (followed by

its code number

At the top right hand:. Name of village (followed by

its code number).r Latitude and longitude (if

available from Head Office).r Council/ Sub-district.t District.. Region.

source and date); iffield. [n either case

sketch a plan as an

l. Date of visit.2. Purpose of visit.3' Onchocerciasis Jbcas: Name of river and/or the tributary to the river.

This is a very important information. As far as possible co-ordinatesmust be established.

4.

5.

6.

7.

8.

Access: Itinerary; state of tlre roacl.

working conditions: where tlre team stays and works.Name of the village chief.Ethnic group(s) and sub-groups.Population: From available censlls data (showingnot available then census done by the team in thecomment on reliability of figures.

9. History and structure of the viilage: If possibleannex.

67

. Origin of the inhabitarrts, stages of settlement, contacts with the

natives and/or modes of land occupancy, important events'

. Layout of the houses, inter-connection between the hamlets and

the village.r social facilities: school, dispensary, youth clubs, etc.

r Socio-political strgcture: Social units (family, lineage, clan) and

political organ ization (traditi onal authorities, tnodern authority)'

10. Activities, resources and economic problems'. Agriculture: land tenure system, location of farms, modes of work

(men, women, children), extension service bodies (governmeutal

or non- governmental), products harvested'

r Other activities: animal husbandry, handicrafts, fishing, etc'

r Infrastructures and structures for trade: roads, markets, marketing

bodies, etc.

11, Present migratiotts:o fmmigration: since when? Origin and rnotivations, modes of

settlement, numerical volume, age groups and Sex concerned,

elvisaged duration of residence, activities of irnmigrants.

. Emigration: since when? Numerical volume' age groups and sex

concerned, destination, motivations, envisaged duration.

12. Particular problents.. Water: what water is used for during the different periods of the

year; how men, women and children use the river and backwaters.

r Schoolchildren: the youth in general.

Other particular problems (modes of sleep, food, dress, pleasure,

etc.).

13. Miscellaneous notes. Questions, problems, interesting facts'

14. Annexes: For example the map of the area (sketched by one of the

team members), photographs (aerial or others), age pyramid etc.

68

Example of a village report

Cdfe d'fvoire (03) Gbando (I9O)

Bondiali regionBondiali disfrictTenhoure counci | (Ghando)

t Date of vt'sit and no. of passage: 24 and 25 April 2001. FirstPaSSage.

2 Purpose of visit: Detailed evaluation.

3 Onchocerciasis focus: Gbanoni or Bagoue, locatedabout 6 kn from fhe village, and Passe, itsfribufary, locafed about 0,5 km away.

Access: Road from Bondiali fo tlilandinani. From Bondiali,Qhando is the second village found after fheBagoue bridge, on the right-hand side of theroad. The left-hand side of the road isoccupied by the Nyafara hills on the norfhernside of which flows the Passe.

Working condifions: Living and working accommodafionin a compound within the village, situafednorfh of fhe chief's house.

6 Name of fhe villaae chief: tlilanudjo Fone.

'ic grouP: Senoufo (code, 060), sub-group of theNyoudougous.

69

Population: EPf enumerated 127 persons, examined g0of then in parasitology. 55.9"2 of them aremen and 44.1% women.

Hisforv and sfructure of fhe village

9.1 Oriain of the inhabitants: The inhabifanfs ofGbando say they have always lived in fhis village

which suffered greatly during Samory's passage.

ff was the capital of Gbando disfrict but lostthaf title to Bondiali recently.

9.2 Layouf of the houses: Qbando has relativelygrouped houses, buf there are no secfions of thevillage, nor do houses have clear delimifafions.

9.3 Social facilities: None. One has fo go fo Bondiali.

9.4 Socio-political strucfure: Chieftaincy is thepolitico-adninisfrafive system. The village chief isassisted by o secretary. The household is the basicsocial unif, followed by the clan. There are fwoclans: thaf of the Fannis, fo which fhe chiefbelongs, and that of fhe Bembas to which thevillage Secretary belongs.

10 Economh Acfivities resources and problems

rc.I Agrrculfure: The village chief is also the landchief. The farms are on the opposife side of theriver. However, fhe women of hhando have hadrice farms on fhe banks of river Passe for a longtime, up to the 1975-1976 farming season. The

main crops are yam, maize, groundnufs, rice and

70

cofton. Rice, cotfon and groundnufs are cashcrops.

Io.2 other acfivities: Rearing of sheep, goafs andpoultry. There are cows foo, all of which belong tothe Fulanis.

10.3 Trade: Nothing fo reporf.11 Present mnraftbns:

ILI Immigrafion: None.11.2 Emigration: out of fhe Jz persons absenf, z0

(15.77") have emigrafed. The main directions areBondiali (8), Abidjan (4) and yamoussokro (5).The main age groups involved are: 10-14 (J), Ii-Ig(3), 20-24 (S) and Zg-29 (J).

LZ Parficular problems:

I2.l wafer: unfil 1925, the village was drinking riverwafer. Since them, if has a covered weil eguippedwifh pump.

P.D. Attioh R.G. Brika26 April 2001

7l

READIF{G A DEC PATCH TEST

The test is read after 24 hours:

r Privacy is essential, since we are asking people to expose themselves.

r Remove the two patches. If there is any cream or dirt under a patch,

clean it away gently with a cotton wool swab soaked in water.

r Now examine, carefully, each of the two rectangles where tl,e patches

were in contact wth the skin. Do this in good liglrt (preferably sunlight)'

If the patch has already fallen off when the person arrives forthe testto be

read, the following procedure is followed:. Read the test. lf at least one patch is positive, record the grades. No

more needs to be done.

. If both are negative, enquire carefully for how long the patch remained

attached to the skin:r lf it remained affached for 3 hours or more, no lnore needs to be

dotre. Simply record the grade.r If it fell off before 3 hourse or if you are not sure, repeat the test

(but note: this will not happen often - when the patches were

applied you asked people to come back if it fell off soon).

The following grades are used to record the results of the test:

Grade 0 Tlre skin looks completely normal - there is no reaction,

there are llo papules.

Grade I There are 1-3 definite raised papules on the area that was

covered by the patch.

Grade 2 There are 4-8 definite raised papules on the area that was

covered by the patch.

Grade 3 There are more than I definite raised papules, but there

are also some areas of normal skin.

Grade 4 Tlre entire skin surface that was covered by the patch is

raised and oedematous - one cannot distinguishindividual papules ('peau d'orange').

72

Note that pre-existing rashes have to be taken into account when doilg thegrading' These will have been noted in the 'Observations' column on thecensus form N602.

The left and right sides are read separately. The results are recorded asfollows on the census form N602:r First clreck the number on the sticking plaster on the villager,s left

wrist, as well as his/ her name.

' In the same row as the number/ narne, fill in the test result as fbllows:. Left side: column SB.. Riglrt side: colamn 41.

Reading a test

73

VERIFTCATIOI\ OF I\EW CASES ;

THE, MIGRATIOI\ HISTORY

The most important objective for the surveillance is the detection of new

infections. For this reason the results of the average of the 2 patch test

grades of the previous survey is compared to the present results' The

iollowing persons are treated as new infections:

. Any persons that were exarnined and found negative at the previous

examination and are now Positive.. Chidren under 10 years who are found to be positive on their first ever

patch test.

For each new infection, a migrntion history must be established at the salne

time as the result of the teit becomes known, to ascertain whether the

person has or has not been residing in an area where onchocerciasis

transmission is known to occur' Note down:t The person's nalne.r The person's 'Individual number''

' Where the person was born.

' Any other places where s/he has lived:I Since the last examination (if s/he had one)'

: Or for tlre past 10 years (if this is her/ his first examination).

r In recording a previous place of residence be sure to specifo:

r Name ofvillage.r Sub-district.e District.r Region.r Country.This is so that the village can be located'

If new infections are proven to have occurred in ildividuals who have

never gone out of the village in question, a sirnilar sllruey is to be carried

out later in the surrounding non-indicator villages. This will be done later

on instruction from Head Office.

74

GIVING IVERMECTIII{ DURING THE VISIT

During the surveillance visit we only give ivermectin to persons withpositive skin snips or patch tests. However the following persons withpositive results may not get it:

I

t

Children less than 5 years old.

Pregnant women (however you can give them the right dose to takehorne, and explain that they may only take it a week after they havedelivered).

Women who are breastfeeding a child which is less than a weekold (however you can give them the right dose to take home, andexplain that they may only take it when the child is a week old).

People who are very sick (however you can give them the rightdose to take home, and explain that they may only take it when theyare feeling better).

You work out the dose according to the person's height, as follows:

r Heisht less than 119 cm I tablet

I Height between 120 and 140 cm 2 tablets

t Height between 141 and 158 cm 3 tablets

. Height 159 cm or more 4 tablets

75

COMPLETII\G SUMMARY SHEETS OFTHE DATA COLLECTET}

After the survey of a village has been completed the consolidated resultsare entered on three speciul fornrs (specimens are attached):

' The first form is for the census data.r The second form is for the results of the parasitological examination.

' The third is the summary of new cases.

First form: Census resultr First enter the identification information: village name and number, and

the date.r In theJirst column write the identity numbers assigned to the families.

' In tl'te second column write the number of individual members in eachfamily.

I In the third to eiglttlt columns enter the number of persons coded 1, 2or 3, 4, 5, 6 and 7 respectively for 'Exam.status'.

r In the last column enter the total number of persons in a family knownto be blind.

' Finally, add up the figures in each column and write the totals at tlrebottom.

76

CENSUS RESULT

Name of villag e= Naga Number of village: I?i Date:21/2/83

Fam. Total 1 2-3 4 5 6 7 BlindI 52 I8 5 I 7 2 il2 24 17 T 2 T 33 I T

4 7 5 25 3 36 6 4 27 I I 3 I I 2I 11 5 I 2 I 2I 3 I I I10 6 T 2 2 T

t1 2T T3 2 2 3 T

12 12 3 3 4 2T3 7 4 I T II4 6 3 2 T

ffi 5 4 T

I6 3 I I T

I7 I I18 3 T I It9 3 320 I I T

2I 7 3 2 2Tofal 201 91 25 25 t8 TI 31 0

77

Second form: Parasitological results

First portiott. First enter the identffication information: village name and number

plus date.

r Then you record the results of the patch test reading by age group and

sex, as in the examPle attached:. since you only test persons from 5 to 20 years of age:

* You leave the rows '0-4', '30-49' and '>50'blank

ir You change the row heading '15-29' to ' l5-20'.I If a person is negative for both patch tests, use the notation '0l0' or

just '0-'.o 1f u p*tson is positive for at least one patch test, record both

figures, e.g. '/0-ll' or'12-21' -

. Count the total number of persons found positive and the total

examined in the age and sex sub-groups. Write the two figures in

the bottom right-hand corner of the corresponding box: e.g. '0117'

for'age 0-4 Male'.r Finally, atthe bottom of the fon-n, record:

* On the left: the total number of males positive and the

total number examined.,r On the right: the total number of females positive and

examined.* In the middle the grand total for both sexes positive and examined.

r It is very easy to miscount, so always count twice and write down the

result only if it is the same both tirnes. Otherwise re-count.

78

Second portiort

' This portion helps you work out the rfiw previlIences, per age groupand overall for the village.

' You copy the scores from the first portion:r Those examined and those positive.r Per age group and per sex:

o Only for the three age groups '5-9', '10-14'and ' 15-20'.

* Change the heading ' I 5- l g' to ' I 5-20'.r Then you calculate the prevalences.

79

PARASITOLOGICAL EXAMINATION RESULTS

Name ofvillage: Naga

M: 3/30

Number of village: | 105 |

4/48

Date: 21/2/2001

T:

80

F: 1/18

Age M F

04

NOTE: This age group is included in theform, since it is likely that youngerchildren will also be tested in the near

future.

5-90-0-0-0-0-

0/50-0-0-0-

0/4

10-140- 0 - 0 - 0- 0- 0- 0 - 0- 0- 0- 0- o- 0- 0-

0/14

0-0-0-0/3

15-201 /0- 3 /3 - 3 /2 -0-0-0-0-0-0-0-0-

3/11

1 / 2 - 0 - 0 - 0- 0 - 0- 0- 0- 0-0 - 0 -

u[1

Here is an example of the second portion of the 'Parasitological examination results' form, after it is filledin:

Name ofvillage: Naga

Numb.er of a r* Date:village:i '"" I Ys 21/2/2001

Ages Examined Positives PrevalenceM F M F M F Total

04

5-9 5 4 0 0 0% 0% o%

10-14 14 3 0 0 0% 07 0%

15-20 11 II 3 T 27.2% 9.f i r8.2%

Totalssol rc

48

3 T

4rc.0% 5.6% 8.3%

8l

Third form: New casesI Enter the identification information: date, passage number, country

code, village code and name of river basin.r Enter the following datafor each new c&se, in the respective columns:

. The persott's nalnes.r The person's family number, individual number, sex and age.r The patch test scores on the left and riglrt sides.r { summary of the person's migration history:

* Migrant YJN: whether or not s/he is a migrant.* Origin.' where s/he lived last, before coming to this village.* Year of anivnl in the village: self-explanatory.r' Observatiorts.' other relevant information, e.g. other places

recentlv visited.

82

OCP/EEU/ ONCHOCERCIASIS CONTROL PROGRAMME IN WEST AFRICA

SUMMARY OF NEW CASES

Date of survey: (month/year) 5 /1998 Passage number: /O /4,/ State: /O /4,/ Villaget /5 /?/6 /3/Basin: Sissili

Name andsurname

FamilyNumber

IndividualNumber

SCX Age MeanMfs lstsnip

MeanMfs 2ndsnip

MigrantYAI

Ori-gin

Year ofarrival in thevillage

Obser-vations

AsepuaKwame HF

066 e 6 2 2 6 5 I 64 5 3 ru

83

HOW TO STORE AI{D FORWARD DATAAFTER A FTELD VTSIT

It is of vital impoftance to organize a data bank for storing theinformation collected. Use boxes about 34 x 25 x | 0 un in size. Everyvillage surveyed should be allocated a separate box to allow room forthe results of the subsequent surveys. Write the name and code of thevillage on each box, e.g.'135'.As the data bank may be damaged or destroyed by termites, fire, etc.,make photocopies of all records and establish a duplicate bank inanother bulding. Keep copies in the national team headquarters and onein the district/regional office.

Forward the data sheets to the person entering the data into a computeras soon as possible, This may be at district/regional level, or at nationalheadquarters.

84

TEACHING AIDSVisual aidsA visual aid is needed to show leamers what the skin looks like for each ofthe five stages of the DEC patch test. possibilities:

' showing the students the photographs (e.g. the one on page 49 above)r Showing them real patients with positive DEC patch tests.

Case studies

Learners need to learn to take a number of decisions.

Case study tto. I : What to do if u sentinel villnge no longer exists, ar rbno longer suitnhle

The epidemiological surveillance team arrives at village X. Last time theywere there they noted that the cooperation of the vilLgers was generallypoor - people were muttering a lot about having to waste two days, uniabout the fact that the otlrer villages around didnl have to put up with this.This time the chief says he frankly doubts whether many #omen willbother to come or to bring their clrildrerr.

. Q :Whar do you do?t I : Arrange a meeting to try to ntotivate them.

At the rneeting you arrange to explain, very few villagers botlrer to attend.Those that are there make it quite clear that while tf,ey might cooperate,many will not.

I e :Ittrhat do yott do?t l -' Yott can't ttse that village since you need close to 100%

attendance,. so choose another village nearby.There are three villages nearby: A, B and c. you visit them all. you findthe following:

t A is close to the river, has 400 inhabitants and the chief says thereis very little migration in or out. He arranges a meeting with thecommunity

-and they agree to help by being tested .u*ry threeyears with the patches. According to your past records the villagewas examined once in the 1970s, and the prevalerrce oronchocercias.is wasn't very high. There are lots of blackflies

85

around.B has 320 inlrabitants and there is a lot of blindness there. tt is

further from the river than A, in fact it is altogether more isolated.

There doesn't appear to be another village between it and the

river. It was alJo examined once near the start of the control

programme, and had a very high prevalence rate with high

miciofilaria counts at that time. The chief tells you that there are

always blackflies around in the wet season' He says he would be

very happy if you were to come around to examine his people

from time to time.C is almost like B. However our original village X lies between

and the river. But there are lots of blackflies, there were lots

cases when it was examined early in the 1980s and the chief

very helpful and keen. The population is about240'

Q :Which village wottld you choose, und v'hy?

itofis

Case stutly no. 2 : Whnt the age is of a person who doesn't know

A woman brings a little girl to the census table. It is her triece, and the

child's mother has died. She has no idea when the child was bom or how

old she is.o Q :What do yott do nov"l: A : look in her moullt; conlpare with the dental chart.

You see she has 4 incisors above, 4 below and} molars below as well.

t Q :Hou, old is she ntore or less?

86

Case study no. 3 : Wltot the age is of a person who doesn'l know

A middle aged man Mr X arrives at the census table for the first time. Hehas no idea how old he is.

: Q :What do yott do tofind our?t I : Ask if he has any personal documents ut home that he ccut

fetch.He says he has no documents - they got wet and spoiled in the last rainyseason.

t Q :What do yott do nov,'?t A : Ask about his stage of life at intportant clutes like

Independence Year; ask if he has a f iend or relatit,e v,ho is moreor less the same age ttnd has docttments ot' kttotvs v,hen he u,asborn.

He can remember that his first son was born a year or two beforeIndependence Year; also he brings a cousin Mr z who says he is two orthree year older than Mr X, and whose identity book shows him to be 47years old.

: Q :With this idormation, what age would you recordfor Mr X?

Cnse study no. 4: When ivermectitr mily or may nol be given

Mrs Y is l8 years old and has a positive patch test. She arrives at theivermectin table to get her treatment.

I Q :What do you do?: 1 :Ffind otrt if she is pregnant, or has just delivered, or is

s ulferin g from any il lne s s.

She is not pregnant and her only child is a year old. She is suffering froma chronic vaginal discharge but feels well otherwise.

I Q : Can she get ivermectin?t l:Yes.

You lrave to work out how much ivermectin she can set.t Q :What do you do nov,?: A : Measnre her height.

She is 145 cm tall.r Q :What dose of ivermectin should she get?

87

ASSESSMEI\T PLAN

It is very important that the learners must leam especially the skills in thismodule to a high degree of competence. The plan for conducting suchassessment is as follows:

SkillsAt the end of each day's practical the trainers meet to assess whether eacl-t

learner has mastered each skill he has to learn. This is done by using theassessment form below. Leamers who are not coping are given furtheropportunities to practice, under supervision. An average final skills rnark of2 or more is a pass.

Knowledge and decisions

' On the last day of the course a short written or oral exam is conductedto see if the leamer has mastered essential knowledge and can makedecisions with that knowledge. This should take the form of a few shortquestions (to assess knowledge) and a few short case studies (to assess

how they use that knowledge to make decisions).

' This test should cover the following areas:. Onchocerciasis: its cause, spread, symptorns and signs, control.r The meaning and importance of epidemiological surveillance.r Criteria for selecting a village to be a sentinel village.r The indications for giving ivermectin during epidemiological

surveillance visits; the dose.. How to store and forward data after a field trip.r Determining a person's age who does not know what it is.

r As always, the test should concentrate on what learners 'must know',and not on what is 'nice to know' . A 5A% mark for the test is a pass.

The decision to pass or to failr d learner must pass both tlre practical and the test to pass. However the

practical mark is clearly much more important than the test mark.

88

Finally the question is: are the trainers happy thatwill be able to perform the job, if he is sent off in aanswer if 'yes' he passes; if not, he fails and has tosome stage.

a particular learnerteam to do it? If there-do the module at

89

SKILLS EVALUATION SHEET

Date:

3 : excellent2:good-passI : poor - needs more practice

Write the score in pencil in lhe relevantblock. TIis means you can chsnge it laterwhen the learner ltas improved.

Learners'names

re for the trip to the villah a villaee effectivel

Discuss problems with villSet up examination facilities in a villaConduct a census of the villaKeep a notebook of correctionsAnalvse data to find 'new infections'Verifv'new infections'Obtain a'migration historv'Adrninister ivermectin correctlSumrnarise all data on 3 formsWrite a 'VillStore and forward data sheets safelPrenare a20Yo solution of DECExplairr the need for tlre test to villaUse the DEC solution to make aApply patclr to the skin over iliac crestsDiscuss how to care for the patch

Read the result of the test at 24 hoursRecord the findinss of the test

Average markfor skills (1, l%,2, 2%,3)

Examiners :