Washington, Aug 1: An avian flu virus is wiping out large numbers of baby harbour seals, after infecting these aquatic mammals with pneumonia, in New England, US.
Wildlife authorities first became concerned in September 2011, when seals with severe pneumonia and skin lesions (eruptions) suddenly appeared along the coastline from southern Maine to northern Massachusetts.
Most were just babies, less than six months and a total of 162 dead or moribund seals were recovered over the next three months, according to scientists at the Centre for Infection & Immunity (CII) at Columbia University’s Mailman School of Public Health, the National Oceanic and Atmospheric Association, New England Aquarium and others, the journal mBio reports.
Pathogen screening was conducted in a subset of afflicted seals, using sensitive diagnostic tools developed at the CII, and a new strain of avian H3N8 influenza virus was identified as the culprit, according to a CII statement.
“When initial tests revealed an avian influenza virus, we asked the obvious question: how did this virus jump from birds to seals?” says Simon Anthony, postdoctoral research scientist at the CII, who led the study.
Based on full genome sequencing and phylogenetic analysis, seal H3N8 descended from an avian strain that has been circulating in North American waterfowl since 2002, which implies recent transmission from wild birds to seals.
(Phylogenetics is the study of evolutionary relatedness among various groups of organisms (for example, species or population).
“Our findings reinforce the importance of wildlife surveillance in predicting and preventing pandemics, says W. Ian Lipkin, director of the CII and John Snow, professor of epidemiology, at the Mailman School of Public Health.
“HIV/AIDS, SARS, West Nile, Nipah and influenza are all examples of emerging infectious diseases that originated in animals. Any outbreak of disease in domestic animals or wildlife, while an immediate threat to wildlife conservation, must also be considered potentially hazardous to humans,” they said.