Decline in Rotavirus Hospitalizations and Health Care Visits for Childhood Diarrhea Following Rotavirus Vaccination in El Salvador

Abstract

A recent postlicensure study from El Salvador showed that the monovalent rotavirus vaccine conferred 76% protection against rotavirus hospitalizations. We further examined the impact of rotavirus vaccination on the national burden of childhood diarrhea to help assess the total public health benefits of vaccination. We compared all-cause diarrhea and rotavirus-specific hospitalization rates during prevaccine year 2006, with postvaccine years 2008 and 2009 in children < 5 years of age from 7 sentinel surveillance hospitals. We also compared annual rates of diarrhea-related healthcare events during prevaccine years 2005 and 2006 with postvaccine years 2008 and 2009 to examine the national burden of healthcare utilization for all-cause diarrhea. Among sentinel surveillance hospitals, rotavirus hospitalization rates among children < 5 years of age declined by 81% (95% confidence interval [CI]: 78%-84%) in 2008 when 2-dose rotavirus vaccine coverage was 50% among infants < 1 year; the decline was 69% (95% CI: 65%-73%) in 2009 when 2-dose vaccine coverage was 61% among infants < 1 year, compared with 2006. The greatest declines were observed in children ≤ 1 year of age, although sizeable reductions were also observed among children ≥ 2 years in 2008. National diarrhea-related healthcare visits during rotavirus season decreased by 48% (95% CI: 47%-48%) in 2008 and by 35% (95% CI: 34%-35%) in 2009 compared with the mean rate from the 2005 and 2006 rotavirus seasons. Rotavirus vaccination had a substantial public health impact on rotavirus disease and overall diarrhea events in El Salvador. Important age-related changes in diarrheal incidence emphasize the need for ongoing rotavirus surveillance after vaccine introduction.