Hospital-based surveillance for rotavirus gastroenteritis among young children in Bangladesh: Defining the potential impact of a rotavirus vaccine program

Background: In anticipation of introduction of a rotavirus vaccine into the national immunization program of Bangladesh, active hospital-based surveillance was initiated to provide prevaccine baseline data on rotavirus disease. Methods: Children 5 years of age and younger admitted with acute gastroenteritis (AGE) (≥3 watery or looser-than-normal stools or ≥1 episode of forceful vomiting) at 7 hospitals throughout Bangladesh were identified. Clinical information and stool specimens were collected from every 4th patient. Specimens were tested for rotavirus antigen by enzyme immunoassays; 25% of detected rotaviruses were genotyped. Results: From July 2012 to June 2015, rotavirus was detected in 2432 (64%) of 3783 children hospitalized for AGE. Eight enrolled children died, including 4 (50%) who were rotavirus positive. Rotavirus was detected year-round in Bangladesh with peak detection rates of >80% during November-February. Most (86%) rotavirus AGE cases were 6-23 months of age. Sixty-nine percent of children with rotavirus had severe disease (Vesikari score, ≥11). Among 543 strains genotyped, G1P[8] (31%) and G12P[8] (29%) were the most common. Conclusions: Rotavirus is a major cause of morbidity in Bangladeshi children, accounting for nearly two-thirds of AGE hospitalizations. These data highlight the potential value of rotavirus vaccination in Bangladesh, and will be the key for future measurement of vaccine impact.