Blood Donor Screening 2009 Blood Donor Screening 2009 --Current Tests & RisksCurrent Tests & Risks

Dr Patrick CoghlanNational Transplantation Services

Australian Red Cross Blood ServicesMelbourne

Source and Type of Source and Type of Regulated Blood ProductsRegulated Blood ProductsSource PlasmaSource PlasmaPlasmapheresisPlasmapheresis

Whole Blood DonationsWhole Blood Donations

Cellular componentsCellular components& Plasma& Plasma

TransfusionTransfusion

Recovered PlasmaRecovered Plasma

Manufacture ofManufacture ofPlasma DerivativesPlasma Derivatives

And inAnd in--vitro reagentsvitro reagents

~1,000,000 units~500,000 donors

~2,500,000 units

~450 tonne

Ref: SHOT Annual Report, 2007

SHOT: Cumulative data 1996SHOT: Cumulative data 1996--20072007

(B/O/T) Donor Derived Viral Infections(B/O/T) Donor Derived Viral InfectionsHBV, HCVHBV, HCV hepatitis, cirrhosis, HCChepatitis, cirrhosis, HCCHIVHIV AIDSAIDSHTLVHTLV Adult TAdult T--Cell Cell LeukaemiaLeukaemia, TSP/HAM, TSP/HAMCMVCMV CMV diseaseCMV diseaseEBVEBV Inf. Mononucleosis, Lymphoma PTLPDInf. Mononucleosis, Lymphoma PTLPDHHV8HHV8 Kaposi Sarcoma (Kaposi Sarcoma (immunocompromisedimmunocompromised))ErythrovirusErythrovirus ((ParvoParvo) RBC ) RBC aplasiaaplasiaDengueDengue DengueDengue FeverFeverCHIKVCHIKV ChikungunyaChikungunya FeverFeverWNVWNV WNMEWNMELyssavirusLyssavirus RabiesRabiesArenavirusArenavirus LymphocyticLymphocytic ChorioChorio--MeningitisMeningitis

PlasmodiumPlasmodium MalariaMalariaBabesiaBabesia BabesiosisBabesiosisTrypanosomaTrypanosoma ChagaChaga’’ss diseasediseaseTreponemaTreponema SyphilisSyphilisBorreliaBorrelia LymeLyme DiseaseDiseaseMycobacteriaMycobacteria TBTBTSEsTSEs CJD, CJD, vCJDvCJD,,

All volunteer donorsHBsAg test

AIDS high-risk exclusions

Anti-HIV testALT/HBcAb tests

Anti-HCV test

Improved HCV tests

1965 1970 1975 1980 1985 1990 1995 2000

Year of Transfusion

% R

ecip

ient

s In

fect

ed

25

20

15

10

5

0

NAT Implementation

Tobler and Busch, Clin Chem 1997.

Blood is much safer now, but is it safe enough?

TGA

Paradigm ShiftALARA ----- Precautionary principle principle

Clinically significant viral infections Clinically significant viral infections by blood transfusion have been by blood transfusion have been

virtuallyvirtually eliminated by:eliminated by:

Increasingly stringent donor eligibility Increasingly stringent donor eligibility criteriacriteriaIncreasingly sensitive/additional Increasingly sensitive/additional serological screening testsserological screening testsNucleic acid amplification testing (NAT)Nucleic acid amplification testing (NAT)

Sources of Residual RiskSources of Residual Risk

Window period (>90% of risk)Window period (>90% of risk)time between exposure to an agent time between exposure to an agent and detection with screening testsand detection with screening tests

Viral variants (strains, subtypes) not Viral variants (strains, subtypes) not detected by current testsdetected by current testsInfectious chronic antibody neg carriersInfectious chronic antibody neg carriersTesting errorsTesting errors

Busch MP. HIV and Blood Transfusions: Focus on Seroconversion. Vox Sang 67(S3):13-18, 1994.

Source: ANZOD

1 in 11 in 10

1 in 100

1 in 1,000

1 in 10,000

1 in 100,000

1 in 1 million

1 in 10 million

1 in 100 million

1 in 1billion

1 in 1trillion

1 in 10billion

1 in 100billion

-6 -5 -4 -3 -2 -1 0 +1 +2 +3 +4 +5 +6

Pat’s Take Home: Current estimates of risk

The Paling Perspective Scale © John Paling

Blajchman - 2002 Calman 1995

MinusculeRisk

MassiveRisk

Neg Min VL

One in 1 Million = Effective Zero

HCVHIV

HBV

HTLV

? O&T

? O&T

? O&T

General AnaesthesiaMistransfusion

TRALITA-GVHD

Cardiac

Metabolic risk in NeonatesUnder-transfusion

Dzik 2003

CMV

vCJD

‘‘Blood borneBlood borne’’ viral transmissibility viral transmissibility

Three primary criteria that generally need to be Three primary criteria that generally need to be met for a virus to be transmitted by blood met for a virus to be transmitted by blood

It gives rise to asymptomatic infection in the donorIt gives rise to asymptomatic infection in the donor

It is present in the bloodstream It is present in the bloodstream

It is able to survive during subsequent It is able to survive during subsequent storage/processingstorage/processing

Safeguarding the blood supplySafeguarding the blood supply

‘‘Safety tripodSafety tripod’’ **1.1. Donor selectionDonor selection

2.2. TestingTesting

3.3. Pathogen reductionPathogen reduction

4.4. [[HaemovigilanceHaemovigilance]]

** FarrugiaFarrugia A. Vox Sang 2004 86: 1A. Vox Sang 2004 86: 1--77

HIV prevalence in persons aged 15 HIV prevalence in persons aged 15 -- 49 49 years in selected countriesyears in selected countries

0 500 1000 1500 2000

Papua New Guinea

Thailand

Myanmar

Cambodia

Spain

United States

Italy

Malaysia

Vietnam

France

India

United Kingdom

Australia

China

Indonesia

New Zealand

HIV prevalence per 100 000

National Centre in HIV Epidemiology and Clinical Research: 2007

Diagnoses of HIV infectionDiagnoses of HIV infection and AIDSand AIDS11

in Australiain Australia

0

400

800

1200

1600

2000

2400

1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005

Year

Num

ber

HIV diagnoses AIDS diagnoses 1. AIDS diagnoses adjusted for reporting delays.

Source: State and Territory health authorities

Donor SelectionDonor SelectionSelect from Select from ‘‘lowlow’’ risk donorsrisk donors

ARCBS ARCBS –– voluntary, non remunerated voluntary, non remunerated Donor education Donor education –– ‘‘riskrisk’’ focusedfocusedComprehensive medical historyComprehensive medical history

Infectious diseases Infectious diseases -- asymptomatic deferral period > asymptomatic deferral period > usually 2x incubation period (e.g. WNV 28 days)usually 2x incubation period (e.g. WNV 28 days)Minimum deferral period after cessation of symptomsMinimum deferral period after cessation of symptomsAdditional deferrals for high risk behaviour, Additional deferrals for high risk behaviour, immunisations, medications, travel, transfusion, immunisations, medications, travel, transfusion, carcinoma etc. carcinoma etc.

How effective is donor selection?How effective is donor selection?

ARCBS studyARCBS studyReducing the risk of transfusion transmissible viral Reducing the risk of transfusion transmissible viral infection through blood donor selection: The Australian infection through blood donor selection: The Australian experience 2000experience 2000--20062006

Mark Polizzotto, Erica Wood, Helen Ingham and Tony Mark Polizzotto, Erica Wood, Helen Ingham and Tony Keller. Transfusion 2008; 48:55Keller. Transfusion 2008; 48:55--6363

6.2 million 6.2 million allogeneicallogeneic blood donations collected by blood donations collected by ARCBS between July 2000 and June 2006ARCBS between July 2000 and June 2006Tested for hepatitis C, hepatitis B, HIV, and HTLV I/IITested for hepatitis C, hepatitis B, HIV, and HTLV I/IIDonors with positive test results contacted for Donors with positive test results contacted for reassessment of risk factors and repeat testingreassessment of risk factors and repeat testing

Prevalence ReductionPrevalence Reduction

Reflects combined impact of education and selectionReflects combined impact of education and selection**Sourced from National Surveillance of Sourced from National Surveillance of NotifiableNotifiable Infectious Diseases ReportingInfectious Diseases Reporting

––

1 in 101 in 1033

55--10 in 1010 in 1033

11--2 in 102 in 1022

Population Population PrevalencePrevalence**

––3.2 in 1x103.2 in 1x10662020HTLVHTLV

3503502.9 in 1x102.9 in 1x10661818HIVHIV

5050--1001009.6 in 1x109.6 in 1x1055605605Hepatitis BHepatitis B

7575--15015013 in 1x1013 in 1x1055818818Hepatitis CHepatitis C

ReductionReductionDonor Donor

PrevalencePrevalenceNumberNumber

(Source: (Source: PolizzottoPolizzotto et al)et al)

Comparing Requirements for Blood TestingComparing Requirements for Blood TestingWestern Developing

Epidemiology Low endemicity High endemicity

HBV < 0.1% > 5-10

HIV < 0.1 > 2-15

HCV < 0.1 > 0.5-12

CMV ± 50 > 90

Blood Bank size >10,000/y < 10,000/y

Test emphasis Specificity Sensitivity

Testing strategy Automated Manual

EIA/NAT Rapid tests/EIA

Who pays Govt/Insurance Patient/family

Cost per unit $ 200 $ 10-40

Source: J-P Allain

CharacterisingCharacterising AssaysAssays

AssayResult

+

-

Presence of Disease

+ -True Positive

(TP)

False Negative(FN)

False Positive(FP)

True Negative(TN)

+ Predictive valueTP/(TP+FP)

- Predictive valueTN/(TN+FN)

SensitivityTP/(TP+FN)

SpecificityTN/(TN+FP)

Probability that test is negative in the absence

of diseasePJC 2000

Probability of a reactive sample being confirmed as positive.

Universal Viral Screening Universal Viral Screening Markers (ARCBS, 2007)Markers (ARCBS, 2007)

Serological Serological markers:markers:

HBsAgHBsAgAntiAnti--HIVHIV--1/21/2AntiAnti--HCVHCVAntiAnti--HTLVHTLV--I/III/II

(Abbott PRISM (Abbott PRISM ChLIAChLIA))O&T donations:O&T donations:

[Anti[Anti-- HBc/AntiHBc/Anti--HBsHBs]]

NAT:NAT:HIVHIV--1 RNA1 RNA

HCV RNAHCV RNA

(Chiron/(Chiron/GenprobeGenprobeProcleix TMA Procleix TMA multiplex)multiplex)

Repeat Reactive IA-1(anti-HIV, anti-HCV,

anti-HTLV)

Test on IA-2

NEG on IA-2: biological false reactive (BFR)

Reactive on IA-2

Immunoblot

ARCBS Sequential Immunoassay (IA) Strategy

Product discard

(NAT non-reactive)

Initial ReactiveIA-1

Blood Safety StrategiesBlood Safety StrategiesAb & Ag ChLIA

(HIV & HCV Antigen) (US$20m/QALY)NAT (US$~2M/QALY)

PatientsDonors------Donation

ScreeningSelection

* VI = Solvent Detergent/InactineMethylene BlueUV/PsoralensRiboflavinViral filtration

haemovigilanceTest System Optimisation•Registration•Supplier accreditation•Supplier audit•Assay evaluation/specification•Batch release certification•Pre-acceptance testing•Automation•Monitoring SPC•EQAS

Viral Inactivation*Fractionation

The transient increase in initial reactive rate (IR) and repeat reactive rate (RR) of a problematic HIV antibody assay.

M J Nightingale et al. Transfusion Medicine, 17,404-412, 2007

Initial reactive rate (IR) and repeat reactive rate (RR) during the ‘settling in’ of an HIV Ab assayM J Nightingale et al. Transfusion Medicine, 17,404-412, 2007

CMV NegLeucodepletionAppropriate Use

How good are current tests?How good are current tests?

Current serological tests for HIV, HCV , Current serological tests for HIV, HCV , HBV, HTLV, CMV are capable of HBV, HTLV, CMV are capable of detecting >99.9 % of infectious detecting >99.9 % of infectious donations. donations.

‘‘Window periodWindow period’’ riskrisk

PRISM Assay PerformancePRISM Assay Performance

99.9499.94

99.9399.93

99.8599.85

99.9999.99

Specificity Specificity (%)(%)

0.300.30226746741,153,6431,153,6431,153,6451,153,645AntiAnti--HTLVHTLV

11.611.61071079249241,153,5381,153,5381,153,6451,153,645AntiAnti--HCVHCV

0.170.1733175217521,153,6421,153,6421,153,6451,153,645AntiAnti--HIVHIV

48.848.81011012072071,153,5441,153,5441,153,6451,153,645HBsAgHBsAg

PPV PPV (%)(%)

confirmed confirmed positivepositive

repeatedly repeatedly reactive reactive

(RR)(RR)

negativenegativedonations donations testedtested

AssayAssay

Source: ARCBS 2006

HIVHIV

HBVHBV

HCVHCV

19961996199419941992199219901990198819881986198619841984

1:1001:100

1:10001:1000

1:10 0001:10 000

1:100 0001:100 000

1:1 000 0001:1 000 000

19981998 20002000

Risk Risk per unitper unit

20022002

Evolution of Approaches to Estimate Transfusion Risks

JAJA--Jan03Jan03

Measured Risk:•Prescreening donor prevalence

•PCR/culture studies

•Recipient SC studies

Modeled Risk: I – WP Model

< 1984< 1984

RetrospectiveCohorts:TTVSNIHTSS

Source: Mike Busch

Viral transmission: Measuring riskViral transmission: Measuring risk

Classical approaches to measure risk (i.e. followClassical approaches to measure risk (i.e. follow--up studies/missed infections in screened donors) up studies/missed infections in screened donors) --too few eventstoo few events

Risk estimates now use mathematical modelling Risk estimates now use mathematical modelling yielding theoretical risk levels based on:yielding theoretical risk levels based on:

Frequency of markerFrequency of marker--negative, window period negative, window period donationsdonations

Rare transmission events (variants)Rare transmission events (variants)

Antibody negative carriersAntibody negative carriers

Procedural testing errorsProcedural testing errors

Assumes that Window Period transmissions Assumes that Window Period transmissions represent the major component of the residual represent the major component of the residual riskriskProbably holds true for HIV and HCV, but less Probably holds true for HIV and HCV, but less so for HBV where chronic infection can be so for HBV where chronic infection can be marked by transient HBsAg detectionmarked by transient HBsAg detection

P = P = λλ x WPx WPwhere P = probability donor gave infectious unit where P = probability donor gave infectious unit

during window period,during window period,λλ = = the incidence and the incidence and WP = window periodWP = window period

IncidenceIncidence--Window Period ModelWindow Period Model

Source: Seed et al ARCBS 2005

P = P = λλ x WPx WPwhere P = probability donor gave infectious unit during where P = probability donor gave infectious unit during

window period,window period,λλ = = the incidence and the incidence and WP = window periodWP = window period

For HIV NAT [For HIV NAT [λλ = 6 x 10= 6 x 10--77 ; WP = 9 days (9/365) = ; WP = 9 days (9/365) = 0.02465]0.02465]

P = P = 6 x 106 x 10--77 x 0.02465x 0.02465= 1.479 x 10= 1.479 x 10--77

or 1 in 6,759,259or 1 in 6,759,259

IncidenceIncidence--Window Period ModelWindow Period Model

Source: Seed et al ARCBS 2005

NAT (US$~2M/QALY)

2005-2006 2006-2007Calendar Years Calendar Years

Virus Screening WP Median MedianTechnology (95 CI) (Point estimate) (Point estimate)

HIV Procleix NAT 9 1 in 69,560,000 1 in 35,256,000(8.0-10.3) (8,319,000– 86,473,000) (8,971,000– 41,558,000)

HCV Procleix NAT 5.4 1 in 12,215,000 1 in 3,211,000(4.9- 6.0) (3,565,000– 47,783,000) (2,855,000– 5,023,000)

HBV Prism HBsAg 38.3 1 in 669,000 1 in 1,927,000(33- 43.7) (447,000– 2,657,000) (678,000– 11,002,000)

HTLV Prism HTLV 1/2 51 1 in 10,549,000 1 in 14,728,000(36-72) (2,664,000– 18,578,000) (3,728,000– 25,059,000)

Seed et al: ARCBS 2008

Transfusion Transmitted Infections: Transfusion Transmitted Infections: Residual Risk Estimates for Periods 2005Residual Risk Estimates for Periods 2005--06 and 200606 and 2006--0707

How does Australia benchmark How does Australia benchmark internationally?internationally?

Residual risk per unit transfusedResidual risk per unit transfused

N/AN/A1 in 640,0001 in 640,0001 in 10 million1 in 10 million1 in 3.1 1 in 3.1 millionmillion

FranceFrance((PillonelPillonel et et al.2005)al.2005)

N/AN/A1 in 450,0001 in 450,0001 in 20 million1 in 20 million1 in 4.5 1 in 4.5 millionmillion

UKUK((SoldanSoldan et et al.2005)al.2005)

1 in 4.3 million1 in 4.3 million1 in 153,0001 in 153,0001 in 2.3 million1 in 2.3 million1 in 7.8 1 in 7.8 millionmillion

CanadaCanada(O(O’’Brien et Brien et al.2007)al.2007)

1 in 3 million1 in 3 million1 in 270,0001 in 270,0001 in 2 million1 in 2 million1 in 2 1 in 2 millionmillion

USAUSA(Dodd et al.2002)(Dodd et al.2002)

1 in 14.7 million1 in 14.7 million1 in 1.9 million1 in 1.9 million1 in 3.2 million1 in 3.2 million1 in 35 1 in 35 millionmillion

AustraliaAustralia(ARCBS 2008)(ARCBS 2008)

HTLVHTLVHBVHBVHCVHCVHIVHIV

Documented NAT Breakthrough Infections Documented NAT Breakthrough Infections

1 (since 2002), no NAT1 (since 2002), no NAT0000UK: (England, Scotland, Wales, UK: (England, Scotland, Wales, No Ireland) + EireNo Ireland) + Eire

SpainSpain

70702211JapanJapanN/AN/A0000AustraliaAustralia

000000Rep. So AfricaRep. So Africa

110011FranceFranceEUROPEEUROPE

ASIA ASIA -- PACIFICPACIFIC

AFRICAAFRICA

000000Greece ("covering 75% of the Greece ("covering 75% of the total blood supply")total blood supply")

992222GermanyGermany

000000ItalyItalyPolandPoland

4 (since 2000); no NAT4 (since 2000); no NAT1144USAUSA000000Canada: (Quebec Canada: (Quebec only)only)000000Canada: (Canada: (exclexcl Quebec)Quebec)

NORTH AMERICANORTH AMERICA

HBVHBVHCVHCVHIVHIVRegion / CountryRegion / Country

M. Busch

HBV: To NAT or Not?HBV: To NAT or Not?

Current screening test is HBsAgCurrent screening test is HBsAg

Should additional Should additional test(stest(s) be introduced for ) be introduced for detection of Hepatitis B?detection of Hepatitis B?

-- Anti Anti HBcHBc

-- HBV DNAHBV DNA

Hepatitis B NAT virusHepatitis B NAT virus--positive blood donors in the positive blood donors in the early and late stages of HBV infection: analyses of early and late stages of HBV infection: analyses of

the window period and kinetics of HBV DNAthe window period and kinetics of HBV DNA

Yoshikawa et al Vox Sanguinis 88 (2), 77-86

HBV NATHBV NATRoche and Chiron have new automated assays Roche and Chiron have new automated assays that include hepatitis B NATthat include hepatitis B NATNeed to be performed in single donor (Chiron Need to be performed in single donor (Chiron UltrioUltrio) or very small pools( Roche S201)) or very small pools( Roche S201)ARCBS participated in a trial to evaluate the ARCBS participated in a trial to evaluate the instrumentationinstrumentationAccurate statistics for hepatitis B transmission Accurate statistics for hepatitis B transmission are unavailable. In the absence of a are unavailable. In the absence of a haemovigilance system transmission rates are haemovigilance system transmission rates are estimated by modelling.estimated by modelling.

Automated NATAnalytical SensitivityAnalytical Sensitivity

-- 95% Limit of Detection of WHO standards (IU/mL)95% Limit of Detection of WHO standards (IU/mL)

NoNo8.48.4(5.0 (5.0 –– 21.7)21.7)

12.212.2(7.3 (7.3 -- 29.2)29.2)

HBV (A) HBV (A) (97/746)(97/746)

YesYes6.06.0(3.9 (3.9 –– 12.5)12.5)

2.02.0(1.4 (1.4 -- 7.4)7.4)

HCV (1) HCV (1) (96/798)(96/798)

NoNo50.550.5(29.6 (29.6 –– 118.2)118.2)

42.242.2(24.8 (24.8 -- 99.3)99.3)

HIVHIV--1 (B)1 (B)(97/650)(97/650)

SignificanceSignificance(P<0.05)(P<0.05)

CobasCobas MPXMPXIDTIDT

Procleix ULTRIO Procleix ULTRIO IDTIDT

95% Detection Limit95% Detection Limit(IU/mL)(IU/mL)WHOWHO

ReferenceReferenceStandardStandard

Margaritis et al. Transfusion 2007; 47:1783-1793

The case of WNV• 2002 first death – blood donation

• FDA challenge – summer 2003

• 2003 WNV NAT

• 2007 – automated NAT

Prevalence & Incidence of HIV, HCV, HBV and HTLV among Musculoskeletal Tissue Donors and First Time Blood Donors

Yao et al . Annals Int Med 148,10; 793-5

22221:345,0001:345,000

44441:172,0001:172,000

WPWPRRRR

HBVHBV

771:500,0001:500,000

66661:55,0001:55,000

WPWPRRRR

HCVHCV

991:400,0001:400,000

22221:161,0001:161,000

WPWPRRRR

HIVHIV

NATNATSero.Sero.NAT: residual risk* NAT: residual risk* reductionreduction

* Estimated probability of viraemia in donor

DDI Risk: Reg BD << FTBD << O&TD

TT TT -- CytomegalovirusCytomegalovirusCMV Abs in 30 CMV Abs in 30 -- 80% blood donors80% blood donors

22--12% 12% AbAb+ capable of transmitting virus+ capable of transmitting virus

WP 42 WP 42 –– 56 days56 days

Residual Risk of seronegative donationResidual Risk of seronegative donation

1:66,000 (1:42,000 1:66,000 (1:42,000 –– 165,000)165,000)

2 2 --3 cases per year3 cases per yearStrategies to eliminate TTStrategies to eliminate TT--CMV:CMV:

CMV CMV AbAb negative bloodnegative blood

LeucocyteLeucocyte depletiondepletion

CMV immune globulin/intravenous immunoglobulinCMV immune globulin/intravenous immunoglobulin

prophylactic acyclovirprophylactic acyclovir

Source: Seed 2008

Sample5,050 random blood donors and 13 seroconversion panels. Applying a modified cutoff of 9AU/mL for the AxSYM IgG MEIA

50135013Efficacy: Efficacy: 99.4%99.4%

20832083Spec: Spec:

98 98 –– 99.0%99.0%

29302930Sens: Sens:

99.8 99.8 --100%100%

totaltotal

20542054--PV 100%PV 100%

2054205400--

29592959+PV 99%+PV 99%

292929302930++totaltotal--++

AxSYMAxSYMIgG IgG MEIAMEIAAssayAssayResultResult(9AU/ml)(9AU/ml)

Resolved CMV InterpretationResolved CMV Interpretation

Seed et al Transfusion 2008; in press

Blood Testing in AfricaBlood Testing in Africa

Most blood centres screen for antiMost blood centres screen for anti--HIV by HIV by ELISA or rapid testsELISA or rapid tests

80% screen for 80% screen for HBsAgHBsAg with rapid testswith rapid tests

< 20% screen for anti< 20% screen for anti--HCVHCV

Few countries have a QA system in placeFew countries have a QA system in place

Kits and equipment are often donated, Kits and equipment are often donated, supply is not sustainedsupply is not sustained

Source: J-P Allain

Simple/Rapid (S/R) TestsSimple/Rapid (S/R) TestsPropertiesProperties

SimpleSimpleInstrumentInstrument--freefreeElectricityElectricity--freefree

TypeTypeAgglutinationAgglutinationMembraneMembrane

ImmunofiltrationImmunofiltration (flow through)(flow through)ImmunochromatographicImmunochromatographic (lateral flow)(lateral flow)

Sensitivity/SpecificitySensitivity/SpecificityHIVHIV 100% / 98.6%100% / 98.6%HBVHBV 99% / 99.6% 99% / 99.6% HCVHCV 100% / 99.4%100% / 99.4%

Source: J-P Allain

Real World Testing –The Need for Simple Rapid Tests:•Rudimentary lab facilities•Poorly maintained equipment•Interruptions to power supply•Unreliable refrigeration•Interruption in supply of tests•Poor training and performance

LACSLEWNDEN2WEE(VEE)CTF

LACSLEPOWWNDEN2EEEHJEVE(VEE)

EEEWEEVEEMAYWNDEN2

EEEWEEVEEMAYSLEWNYFDEN2

SINCHIKWNYFDEN2TAH

SINPOW(TBE)WN(TAH,INK)

CHIKSINPOW(TBE)JEWNSSH

RRBFSINMVEDEN2

Global Distribution of Major Human Flaviviruses

2010

nanobiotechnologies

1990

Ag / Ab

serology

2000

NAT

molecular biology

Microarrays ?

genomics

Emerging technologies

AcknowledgementsAcknowledgements

ARCBSARCBS

Clive SeedClive Seed

Angelo Angelo MargaritisMargaritis

Phil Phil KielyKiely

Dr Tony KellerDr Tony Keller