1. Introduction
RV infection, diarrheal disease, Rotavirus, diarrhea, infection, deaths
DISEASE, INFECTION, SECONDARY, DIARRHEAL DISEASE
A correlate of protection for rotavirus (RV) has not been consistently identified. Shedding of RV following an oral rotavirus vaccine (ORV) challenge has been investigated as a potential model to assess protection of parenteral RV vaccines. We previously showed that shedding of a challenge ORV dose was significantly reduced among recipients of a parenteral monovalent RV subunit vaccine (P2-VP8-P[8]) compared to placebo recipients. This secondary data analysis assessed the association between fecal shedding of RV, as determined by ELISA one week after receipt of a Rotarix challenge dose at 18 weeks of age, and serum RV-specific antibody responses, one and six months after vaccination with the third dose of the P2-VP8-P[8] vaccine or placebo. We did not find any association between serum RV-specific immune responses measured one month post-P2-VP8-P[8] vaccination and fecal shedding of RV post-challenge. At nine months of age, six months after the third P2-VP8-P[8] or placebo injection and having received three doses of Rotarix, infants shedding RV demonstrated higher immune responses than non-shedders, showing that RV shedding is reflective of vaccine response following ORV. Further evaluation is needed in a larger sample before fecal shedding of an ORV challenge can be used as a measure of field efficacy in RV vaccine trials.Rotavirus (RV) occurs globally and causes severe dehydrating diarrheal disease in young children. In 2013, it was estimated that 215,000 children died as a result of RV infection. This corresponded to 37% of all deaths as a result of dehydrating diarrhea amongst children less than 5 years of age, of which more than 90% occurred in low- and middle-income countries (LMIC) [One of the major factors hindering the development of RV vaccines is the lack of a reliable correlate of protection for RV, which can serve as a proxy indicator of protection against disease [Upon infection with either naturally occurring RV or live-attenuated ORV strains, the viral strains replicate within the gut and are shed in the stool until the immune system can mount sufficient response to clear the infection [This secondary data analysis assessed the association between fecal shedding of RV following a challenge dose of Rotarix and serum RV-specific antibody responses, one and six months after vaccination with the third dose of the parenteral monovalent RV subunit vaccine (P2-VP8-P[8]) or placebo.