IPV in Moderate to Severe Chronic Malnourished 9-12 Month Old Children in Karachi.

Chronic malnutrition is associated with lack of effective gut immunity which is a possible explanation for why we see polio cases among a proportion of children who have received 7 or more doses of OPV.Our proposed idea is to evaluate if IPV antigen given later in life may act together to boost humoral and mucosal immunity in children belonging to low-income background in Karachi who have moderate to severe chronic malnutrition (height for age Z score less than -2SD). We also intend to compare eIPV + OPV with OPV only in non-malnourished infants at 9 -12 month of age. Thus, the proposed study is a combination of two trials, with study population stratified by nutritional status, each with a reference arm (bOPV) and an experimental arm (bOPV plus IPV).