Isolation and molecular characterization of a H5N1 virus isolated from a Jungle crow (Corvus macrohynchos) in India.

In 2008, India experienced widespread outbreaks of H5N1 virus in West Bengal, Tripura, and Assam. The virus was detected in Kamrup district of Assam in November 2008 and subsequently spread to eight more districts. Two Jungle or Large billed crows (Corvus macrohynchos) were found dead in a hospital campus at about 8 km from the foci of initial detection of the virus in the same district. One of the crows was positive for H5N1 avian influenza virus by virus isolation, real time RT-PCR, and RT-PCR tests. Full length sequencing of all the eight segments of the virus was carried out. The phylogenetic analysis indicated that all the eight genes grouped with clade 2.2 viruses and were closely related to the human isolate of Bangladesh and avian isolates from India, Bangladesh, Kuwait, Germany, and Saudi Arabia. The molecular analysis indicated avian receptor (alpha 2,3 sialic acid) specificity, susceptibility to oseltamivir and amantadine group of antivirals and lower pathogenicity to mice.