Polio Research Activities in India

Dr Sunil BahlWHO-India, NPSP

15 March 2012

IEAG recommendations and follow up actions

Recommendations of IEAG (July 2011):– Seroprevalence study in UP-Bihar– Accelerate research & product development

agenda (e.g. mucosal immunity, mathematical modelling, safe & affordable IPV approaches)

Studies completed during 2011– Seroprevalence study in UP & Bihar– Mucosal immunity study in Moradabad

Seroprevalence study, UP & Bihar-August 2011

• Objectives of study:– Assess seroprevalence to all poliovirus types– Compare seroprevalence of 2011 with 2010– Compare seroprevalence among three age sub-

groups

• Study age groups: 6-7, 8-9 and 10-11 months

10 high risk blocks each in West UP and Bihar

Western UP Bihar

20 children from each of 3 age groups in each block

Sample Size: 600 (UP) + 600 (Bihar) = 1200

Seroprevalence (6-11 month infants) – UP, Bihar: 2011

Type 1 Type 2 Type 3Percent

seropositive

Median SIA doses

Median RI doses

7 7

2

8

3 3

Seroprevalence in different age groups – UP, Bihar: 2011

6-7 months 8-9 months 10-11 monthsPercent seropositive

> 0.05 < 0.05 < 0.05p value

Comparative seroprevalence in 6-7 month infants : 2011 vs 2010 High Risk Blocks - UP & Bihar

2010 2011

Percent seropositive

p value < 0.01 < 0.01> 0.05

Mucosal immunity study-Moradabad, Oct to Dec 2011

Key Objectives:• Assess baseline mucosal immunity & if there is

waning of mucosal immunity in older age groups

• Evaluate which polio vaccine (IPV or bOPV) is more efficient in boosting mucosal immunity

• Assess correlations between humoral and mucosal

immunity in different age groups

Ten study sites for mucosal immunity study-Moradabad

Mucosal immunity study - study populationArm A: bOPV

6-11 mthsN=110

5 yearsN=110

10 yearsN=110

Arm B: IPV

6-11 mthsN=110

5 yearsN=110

10 yearsN=110

Arm C: No Vaccine (Control arm)

6-11 mthsN=110

5 yearsN=110

10 yearsN=110

•Study subjects distributed into three study arms

•Total sample size:110 children x 3 age groups x 3 study arms (990 children)

•110 children of three age groups in each arm

Mucosal immunity study - Study Design

BloodStool

Crevicular fluid

Arm A:bOPV

Arm B:IPV

Arm C:No

Vaccine(Control

arm)

Day 0

Blood

Day 7

BloodStool

Crevicular fluid

Day 28

Stool

Day 28+3

Stool

Day 28+7

Stool

Day 28+14

BloodCrevicular fluid

Day 56

bOPV Challenge to children in all arms

Mucosal immunity study- status

• Field implementation completed in December 2011• 989 subjects enrolled• 948 (96%) enrolled subjects completed study for all

samples• Samples collected

– Stool samples: 4871 – Blood samples: 2935 – Crevicular fluid samples: 1966

• Testing of samples ongoing in ERC Mumbai• Aliquot of samples being sent to CDC, Atlanta

Proposed Polio Research Activities in India : 2012-2013

Research activities proposed, 2012-2013

1. Seroprevalence study in Western UP & Bihar 2. Assess different bOPV products 3. Assess strategies for a safe tOPV-bOPV

switch4. Pilot to assess feasibility of IPV

administration in a mass campaign5. Assess social determinants of vaccine

refusals (survey for social networking analysis)

Seroprevalence study, UP & Bihar 2012• Objectives:

– Assess seroprevalence to all poliovirus types & compare levels with previous years

– Compare seroprevalence between HR and non- HR blocks

• Similar design as in 2011 except: include 5 High Risk (HR) blocks and 5 adjoining non- HR blocks (instead of 10 HR blocks)

• Age group 6-11 months

bOPV assessment study• Generate data on immunogenicity and safety of

additional bOPV products for potential licensing by national regulatory authority (DCGI) in India

• Demonstrate superiority of 2 doses of bOPV of

different manufacturers over tOPV for seroconversion to types 1 and 3

• Additional options for bOPV supply to meet high vaccine requirement in India & globally – important specially for the endgame strategy

Study to facilitate tOPV-bOPV switch under EPI

• Compare immunogenicity against poliovirus types 1 and 3 by bOPV & tOPV given as part of routine EPI schedule

• Assess gain in immunity (booster effect) of a full dose or fractional dose of IPV when added to tOPV or bOPV at 14 weeks (DPT3 contact) in EPI schedule

• Assess operational feasibility of intra-dermal IPV fractional dose using BCG syringe

Pilot administration of IPV in mass campaigns• Assess

– operational & communication challenges– coverage achieved– safety

• Co-administration of IPV & OPV at fixed sites/ house- to-house/in the street during campaign

• Pilot in 3 blocks of a Western UP district– Block 1: OPV + IPV full dose given IM using conventional

syringe– Block 2: OPV + IPV fractional dose given ID using needle free

device – Block 3: Only OPV

Survey for social network analysis• Areas of significance resistance/refusal to polio or other

vaccines persist: e.g. Malegaon, West Bengal etc.

• Assessment of community acceptance/refusal behaviour for polio and other vaccines

• Examine whether social connections to individuals with specific socio-demographic attributes are related to refusals

• Determine the extent to which non-compliant households in an area are connected and influence each other

• Identify how to leverage social networks for promoting polio vaccine compliance

Question for the IEAG

Are the studies/surveys proposed in line with current programme needs in India?

Thank You