Effectiveness of rotavirus vaccine against Severe rotavirus gastroenteritis: A case-control study

Abstract

Background: Since 2006, the rotavirus vaccines that are licensed and used worldwide are Rotarix and Rotateq. Both vaccines have shown a 72-100% efficacy in the prevention of severe rotavirus disease over a 3-year follow-up period. Objective: To evaluate the effectiveness of monovalent oral rotavirus vaccine in reducing the severity of acute diarrhea in children under two years of age at the Pediatric Emergency of the Dr. Mario Catarino Rivas National Hospital (HNMCR) from January 1, 2014 to May 20, 2016. Patients and Methods: A case-control study was performed in children under 2 years in surveillance for rotavirus gastroenteritis and admitted to the pediatric emergency room of the HNMCR. The sample size was 83 cases and 83 controls. The sociodemographic characteristics were analyzed by frequency and percentage and the effectiveness of the vaccine through the odd ratio. Results: the prevalence of rotavirus diarrhea in vaccinated infants was 45%, in non-vaccinated infants 76% with an Xi2 of 7.95 (p = 0.005). The effectiveness of the vaccine for cases of severe diarrhea vaccinated with 1 dose was 86% (OR = 0.14 [51.5-95.9]). For 2 doses, it was 98.99% (OR = 0.011 [42-99.98]). Conclusions: Children not vaccinated against rotavirus presented more severe cases of diarrhea, in contrast to children vaccinated with 2 doses, where the vaccine was effective (EV = 98%), presenting in most cases of moderate diarrhea.