Changing pattern of genotypic circulation of human bocavirus variants associated with acute gastroenteritis in Pune, Western India: A 5-year retrospective study.

Human bocavirus (HBoV) has been frequently associated with acute gastroenteritis. A 5-year retrospective study was undertaken to understand the circulation pattern and genotype distribution of HBoV in acute gastroenteritis cases in Pune, Western India. A total of 985 stool samples collected from sporadic acute gastroenteritis cases and asymptomatic controls (2007-2011) from children (≤5 years) were examined for the presence of HBoV. HBoV1 was detected throughout the study period while HBoV2 during 2007-2010, HBoV3 in 2007-2009 and in 2011, and HBoV4 in 2009 and 2011. Interestingly, HBoV2 was observed to be predominant in 2007 while HBoV1 and HBoV2 were detected at an equal frequency in the year 2008. HBoV1 was predominant from 2009 onwards. The present study highlights the changing pattern of genotypic circulation, emergence, and re-emergence of HBoV variants in acute gastroenteritis cases over a 5-year study period in Western India. The severity of gastroenteritis is reported to vary with HBoV genotypes. Thus, the present study emphasizes the need for routine HBoV surveillance in acute gastroenteritis cases from other parts of the country. This data will be valuable in the current scenario because implementation of rotavirus vaccination has led to the rising of other enteric viruses associated with the disease.