Genomic diversity of group A rotavirus strains in patients aged 1-36 months admitted for acute watery diarrhoea in northern India: a hospital-based study.

The diversity and capacity of human rotaviruses for rapid evolution and genetic reassortment suggests that rotavirus vaccine should be designed to provide heterotypic protection. The objective of the present study was to provide information on the circulating genotypes of rotavirus and allied baseline epidemiology in Lucknow, India. In a cross-sectional study, the prevalence of rotavirus G-P types was studied in patients aged 1-36 months with acute watery diarrhoea. Various sociodemographic, environmental and clinical factors were assessed as potential predictors of rotavirus infection; 412 patients with acute watery diarrhoea were recruited into the study from September 2004 to April 2008 and rotavirus was identified in 19.2% (79/412) cases using ELISA and PAGE. The genotypes identified were G1 (38.0%), G2 (15.2%), G3 (16.5%), G9 (10.9%), G4 (5.1%) and mixed G types (10.1%). The most common G-P combinations were G1P[8], G3P[6], G1P[6] and G2P[8]. Rotavirus diarrhoea was found to occur throughout the year with a single peak in winter months (November-January). Rotavirus diarrhoea was found to be associated with children not currently breast fed (adjusted OR 2.2, 95% CI 1.3-3.7, p 0.004), children < or =7 months of age (adjusted OR 1.1, 95% CI 1.0-1.1, p 0.002) and children with severe dehydration (adjusted OR 1.8, 95% CI 1.1-3.0, p 0.03) using multivariate logistic regression. A high degree of strain diversity of rotavirus G and P types was detected. Rotavirus was found to be associated with dehydrating diarrhoea, particularly in children aged 0-7 months, placing them at increased risk of mortality.