Int. J. Environ. Res. Public Health 2012, 9 909 Figure 8. Phylogenetic tree based on the partial nucleotide sequences of 3C-3D junction region (185 bp) of AiV strains. The strains of the present study are in bold face. Scale indicates genetic distance. 3.5. Environmental Investigation The inspection of the localities affected by the outbreaks of gastroenteritis indicated the existence of densely populated slums with poor hygienic practices and sanitary conditions. The toilet facilities were shared by the residents of the localities. These localities were supplied with water twice daily through age-old pipes by Municipal Corporation. Examination of drinking water and drainage systems of the affected areas revealed the occurrence of both on the same route and leakages in the pipes supplying drinking water and in those of drainage. However, the water samples collected in March, 2006 from two different sites were tested negative for seven different enteric viruses. 4. Discussion To date, the occurrence of more than one enteric virus in gastroenteritis outbreaks has been reported from many countries [33,34]. However, only a single viral agent associated gastroenteritis outbreaks have been reported from India [24,35-37]. Most of these outbreaks except a few remained to be characterized for the genotypic specificities of causative viral pathogens. The present study describes detection of the multiple enteric viral infections in the two outbreaks of acute gastroenteritis occurred in southern Mumbai in 2006. A marked increase in the occurrence of cases of gastroenteritis in about a