Clinico-Epidemiological Profile and Genetic Characterization of Rotavirus Strains Among Children Aged Under 5 Years Hospitalized with Acute Gastroenteritis in Karnataka, India

Objectives: Rotavirus is the most frequent cause of severe acute gastroenteritis (AGE) in children aged under 5 y in India. This study aimed to determine the proportion of rotavirus gastroenteritis in children aged under 5 y admitted with AGE and to characterize the circulating genotypes after implementation of rotavirus vaccination within the Universal Immunization Program (UIP) in Karnataka, India. Methods: This multicenter, cross-sectional observational study included all children aged under 5 y with AGE admitted to four hospitals in Karnataka. Their demographic and clinical characteristics were recorded using a predesigned electronic form. Stool samples were tested for rotavirus using an enzyme-linked immunosorbent assay (ELISA), and all ELISA-positive samples were genotyped using polymerase chain reaction. Results: Of the 433 children enrolled, 405 had a stool sample tested for rotavirus, of which 97 (23.9%) were positive. The prevalence of rotavirus was highest among children aged 12–23 mo (41.2%), followed by infants aged 24–59 mo (26.8%). Among the 97 rotavirus-positive children, the predominant clinical manifestations were vomiting (95.9%), fever (79.4%), and severe to very severe dehydration (87.6%). G3P[8] (54.2%) was the most common genotype, followed by G1P[6] (17.8%) and G2P[4] (11.5%). Conclusions: Of the children admitted with AGE, 23.9% tested positive for rotavirus, with the highest burden in children aged 12–23 mo. The predominant genotypes were G3P[8], G1P[6], and G2P[4]. Ongoing genotypic surveillance is warranted to assess the impact of rotavirus vaccination on the incidence of rotavirus AGE and circulating rotavirus genotypes in the population to inform rotavirus vaccination strategy.