1668. No Impact of Nutritional Status on Oral Polio Vaccine shedding after Vaccination of Under 5 Children in Rural Mexico

Abstract

BackgroundAs wild poliovirus is nearing global eradication and countries switch from Oral Polio Vaccine (OPV) to Inactivated Polio Vaccine (IPV), preventing circulating vaccine-derived poliovirus is a top priority. However, the circulation of OPV serotypes remains a concern in undervaccinated communities. We sought to examine the relationship between pediatric nutritional status and OPV shedding based on length-for-age categorizations. Mexico provides a natural environment to study these patterns as it provides routine IPV immunization and bi-annual OPV campaigns.MethodsWe enrolled 466 households with children eligible for OPV before the February 2015 national health week from 3 semi-rural Indigenous communities near Orizaba, Mexico. In each community, a different proportion of eligible children received OPV (10%, 30%, 70%), with a total of 155 vaccinated children. OPV shedding was measured by RT-qPCR detection of OPV in samples collected serially over 10 weeks. Anthropometric measurements were collected and compared with the WHO Multicenter Growth Reference Study growth curves to assign stunting. Associations between stunting, OPV shedding, and shedding duration were tested by Fisher exact test and Wilcoxon-Man-Whitney Test (α = 0.05).ResultsSamples of fecal OPV isolates were collected over time and analyzed from 148 vaccinees. 25 (17%) of the vaccinees were stunted. There was no relationship between pediatric stunting and likelihood of ever shedding any serotype of OPV (P = 0.82). The mean duration of OPV shedding by stunted and non-stunted children differed, but not significantly (10.9 days vs. 9.3 days, respectively, P = 0.32). We did not find any statistically significant differences between stunting status and shedding of any individual OPV serotype.ConclusionFurther understanding of factors related to OPV shedding is necessary to approach efficient worldwide poliovirus control. We found no relationship between stunting status and both OPV shedding and shedding duration post-vaccination, suggesting that nutritional status does not play a role in OPV shedding. The ongoing analysis includes longitudinal analysis of OPV shedding patterns by nutritional status, and the impact of stunting on viral load and reversion of OPV to vaccine-associated paralytic polio mutants.Disclosures All authors: No reported disclosures.