Molecular epidemiology of Rotavirus diarrhea among children in Nepal: Emergence of G12 and G9 strains

Abstract

Introduction: Rotavirus is the leading cause of diarrhea and dehydration among infants in both developed and developing countries. The primary objective of this study was to find the magnitude of rotavirus disease burden and genotypic variations of rotavirus.

Methodology: Questionnaires and stool samples were collected from 1003 enrolled children under 5 years of age attending tertiary care Children’s Hospital with acute watery diarrhea during January to December 2012. Rotavirus in stool samples was detected by Enzyme Immuno Assay (EIA) and strains detected from rotavirus positive samples were genotyped by Reverse-Transcription Polymerase Chain reaction (RT-PCR).

Results: Among these, 356 (35.4%) cases were positive for rotavirus by EIA, among the positive cases, 344 samples underwent genotyping by RT-PCR. Rotavirus positive cases were predominant in children who were admitted to the hospital which was 37.8% (115 out of 336). Overall G12 was the most prevalent genotype (52.3%), followed by G1 (17.7%), G2 (10.17%) and G9 (8.1%). The P types identified were P[6] (55.23%), P[8] (20%), and P[4] (12.5%).

Conclusion: The study reveals that rotavirus gastroenteritis accounted for more than one-third of all cases of acute diarrhea. Use of rotavirus vaccines may reduce of high burden of rotavirus diarrhea in children. Emergence of G12 and G9 strains proves the immediate need of vaccine in Nepal.