Rotavirus vaccines Rotavirus vaccines

Is a road map needed for Is a road map needed for introduction to the EPI in introduction to the EPI in

Sri Lanka ?Sri Lanka ?

Dr. Pushpa Ranjan Wijesinghe, MDConsultant Epidemiologist

Immunization Summit -2010

Consensus statement Consensus statement Immunization summit-2007Immunization summit-2007

• Current rotavirus vaccine is less effective against the serotype G9 which is the second commonest reported serotype after G3 which is the commonest

• Hence, introduction of rotavirus vaccine to Sri Lanka should be considered at a later date.

• Rotavirus surveillance activities should be extended and strengthened further.

What is known about rotavirus in SL ?What is known about rotavirus in SL ? Authors No of

Rotavirus + patients

No of Diarrhea patients

% Rotavirus +

patients

Mendis L et al (1980) 98 326 30.1%

Chandrasena et al (2006) - NCTH 126 606 20.8%

EPID Unit / IVI study phase I

(2005-2007)

428 1806 23.9%

EPID Unit / IVI study phase II

( July 2008- June 2009)

182 624 29.1%

EPID Unit / WHO

( July 2008- Dec 2009)

88 343 25.7%

EPID Unit / WHO (Jan – March 2010) 103 360 28.6%

WhatWhat are the circulating strains ?are the circulating strains ?

• What was detected in the phase I

• Detection of antigens by enzyme-immunoassay

(EIA)

• WHO Reference lab was set up in Chennai – 2010

• Strain identification – from this month

What are the circulating strains ?What are the circulating strains ?

Type G1 G2 G3 G4 G9 mixed NT Total

P4 0 4 0 0 0 0 1 5

P6 0 0 0 0 0 0 1 1

P8 6 0 17 0 14 4 13 54

P9 0 0 0 0 0 0 0 0

mixed 0 0 0 0 0 0 0 0

NT 3 3 13 0 14 0 0 33

Total 9 7 30 0 28 4 15 93

SOURCE : Epidemiology Unit

Epidemiology of rotavirus diarrheaEpidemiology of rotavirus diarrhea

Source

Rate of gastroenteritis 1119.4/100000 population

(under estimate ?)

AHB 2007

Expected number of diarrhoeal diseases among under five

19477 Based on

AHB 2007

Mean incidence rate of Rotavirus diarrhoea

26.4%

(95% CI = 22.8%-30.0%)

Based on

all studies

Expected number of rotavirus cases per year

5142 (4440- 5843) Based on

all studies

Estimate of Rota specific deaths for Sri Lanka

1500 per year

Case Fatality Ratio = 29%/?

(Over estimate ?)

CDC

Efficacy/Effectiveness of monovalent RV(Rotarix)

Efficacy of preventing

severe diarrhoea

South Africa & Malavi combined

61.2% ( 95% CI-44-73%)

Efficacy of preventing

severe diarrhoea

South Africa 76.9% (95% CI-56-88%)

Efficacy of preventing

severe diarrhoea

Malawi 49.5 % (95% CI-19-68%)

Efficacy of preventing

severe diarrhoea

China, Hong Kong, Taiwan & Singapore

96.1%

Effectiveness of preventing

severe diarrhea

El Salvador 74% ( 95%CI- 51%-89%)

Effectiveness of preventing

very severe diarrhoea

El Salvador 88% (95% CI- 47%-97%)

Efficacy/Effectiveness of Pentavalent RV(Rotateq)Efficacy of preventing

severe diarrhoea

Africa 64.2% (95% CI -40%-79%)

Efficacy of preventing

severe diarrhoea

Asia 51 (95% CI -13%-73%)

Effectiveness of preventing

severe diarrhoea

US 85%-95%

Effectiveness of preventing

Hospitalization needing IV fluids

Nicaragua 46%(95%CI-18%-64%

( children under 2 years)

Effectiveness of preventing

severe diarrhea

Nicaragua 58% ( 95 % CI = 30%-74%)

Effectiveness of preventing

very severe diarrhoea

Nicaragua 77% ( 95% CI- 39%-92%)

Source – WHO

Source : WHO

Are these vaccines safe ?Are these vaccines safe ? • Recommendations of GACVS

– Vaccines are safe – Risk of intussusception ruled out with confidence– No data to support increased risk of intussusception

when administered outside the age range • 6–15 weeks for the first dose• 32 weeks for the second dose

– No interference with OPV and other EPI vaccines – OPV inhibit the response of the first dose of Rota

vaccines – No change in clinical status of

• HIV infected children• Children born to HIV infected mothers.

Update on rotavirus vaccinesUpdate on rotavirus vaccines • FDA recommendations – USA

• Addition of Severe Combined Immunodeficiency as a Contraindication

• DNA from porcine circovirus type 1(PCV1) in the vaccine (Monovalent RV)

• Fragments of DNA from PCV1 and from a related porcine circovirus type 2 (PCV2) (pentavalent RV)

• Resumption of using both vaccines• strong safety records-trials/post marketing surveillance • Benefits > theoretical risks

• Follow-ups by the FDA• Clinicians to inform parents – non availability of a safety risk

Can Rotarix be incorporated into Can Rotarix be incorporated into the EPI schedule ?the EPI schedule ?

• 2 & 4 months schedule – effectiveness demonstrated

• 6 weeks , 10 weeks schedule - effectiveness not

demonstrated

Can Rotateq be incorporated into Can Rotateq be incorporated into the EPI schedule ?the EPI schedule ?

• Rotateq vaccine – 3 dose schedule only used in clinical trials – 6, 10, 14 weeks

• General guidelines • first dose of either RotaTeq or Rotarix

– at age 6–15 weeks.

• The maximum age for administering the last dose of either vaccine– 32 weeks.

Preventable number of Rotavirus cases by live Preventable number of Rotavirus cases by live

attenuated monovalent vaccine in Sri Lankaattenuated monovalent vaccine in Sri Lanka Non vaccinated scenario

Vaccinated – vaccine recipients (90%)

Vaccinated – vaccine non recipients

(10%)

Total cases prevented by vaccine

Rotavirus infection

5142 532 514 4096

Target population – under five children Efficacy – 86 % with 2 doses of monovalent RV vaccineVaccine coverage – 90%

What are the costs involved ?What are the costs involved ? Approximate cost for vaccines

7 $

per a dose

12.4 $ a dose

(376843 X 7 $ X 2)

(376843 X 12.4 $ X 2)

52 75 802 $

per year

9345706 US $

Treatment cost in a non vaccinated scenario

33 $ per a case

( 33$X5142)

169686 $

per year

Treatment cost in a vaccinated scenario

33 $ per a case ( 33$X1046)

34518$

per year

Treatment cost saved from vaccination

135168 $ (0.14 million)

per year

Cost per case averted

Scenario I

Scenario II

1288 US $

2281 US $

What are the costs involved ?What are the costs involved ? Approximate annual cost for vaccines 7 $

per a dose

2 dose schedule

5 million US $

Average cost of an episode of rotavirus diarrhoea hospitalization

Rs. 3626 (US$ 33)

Cost saved through averting rotavirus hospitalizations per year

US$ 0.26 million.

Deaths averted per a year 8

Hospital-based study of the severity and economic burden associated with rotavirus diarrhea in Sri LankaNilmini Chandrasena ,*, Shaman Rajindrajith b, Ahmed Kamruddin c, Arunachalam Pathmeswaran d and Osamu Nakagomi e

Journal of Pediatric Infectious Diseases 2009; 4(4)

FutureFuture • Rotavirus disease burden study

• General population• Among high risk groups

• Morbidity cost study

• Economic analysis

• Expansion of surveillance to other areas• semi urban, rural ,slum, estate settings

• PCR training for the virological focal point @ MRI ( WHO support) • Strain identification @ the MRI

• A large base of rotavirus strains

Discussion pointsDiscussion points • Is there a need for introduction of rotavirus vaccine ?

– present & future

• If so, what will be the time line ?

• If so what approach do we need ?– Population or high risk

• What should be the risk groups – Role of epidemiology and disease surveillance information

• What will be the communication strategy for the community– Perception – all cause remedy for all diarrhoea – One strategy in the intervention package

• What and how can NPI learn from the private sector ?

• What will be the future direction of rotavirus surveillance in Sri Lanka ?

Acknowledgement• Dr.Nihal Abeysinghe• Dr.Paba Palihawadana• Dr. Sudath Pieris• Dr. Ranjith Batuwanthudawe• Dr.Geethani Galagoda• Dr.Sarath Silva• Dr. Kalyani Guruge• Dr. Padmakanthi Wijesuriya• Dr.Paul Kilgore• Dr. Niyambat Batmunkh –IVI• Dr.Aparna Singh Shah• Royal Murdoch children’s hospital – Melborne • International Vaccine Institute• GAVI’s ROTAADIP• WHO- SEAR & HQ-Geneva• Asian Rotavirus Surveilance Network