RESUMO
The effect of diarrhea on oral poliovirus vaccine (OPV) failure was evaluated using data from Brazil, where 728 infants were immunized at birth (OPV1) and approximately 6 (OPV2), 10 (OPV3), and 14 (OPV4) weeks. Recent diarrhea history was significantly associated with increased vaccine failure only after OPV2 for poliovirus types 2 and 3. In multivariate models, controlling for breast feeding, season of vaccine administration (type 3 only), maternal antibody (type 3 only), and immunization campaign exposure (type 3 only) strengthened this effect. Diarrhea at OPV receipt was associated with vaccine failure to poliovirus types 1 and 3 only after OPV2. These data support the current recommendation that children with diarrhea receive OPV and be reimmunized once their illness resolves. Expanding this recommendation to include children with a recent diarrhea history should be considered. While the effect of diarrhea on vaccine failure may be limited to OPV2, programmatic realities may preclude dose-specific recommendations.
