H5N1 virus my be adapting to pigs

An excerpt from CIDRAP:

"Scientists report that H5N1 avian influenza viruses may be adapting to pigs, as evidenced by the finding that H5N1 viruses isolated from pigs in Indonesia were less harmful to mice than were H5N1 viruses from chickens.

The finding suggests that in growing in pigs, the virus may have become less harmful to mammals in general, the authors report. That sounds reassuring, but the authors say it may mean the virus is one step closer to turning into a human pandemic strain. "

.....


:The authors offer this interpretation of their findings: "Since our swine strains were isolated from pigs with no apparent influenza-like symptoms, the decrease of pathogenicity in mice suggests that the H5N1 viruses may have lost their pathogenicity in mammals during replication in pigs. Given that for the H5N1 viruses to cause a pandemic, they would likely become attenuated in humans, becoming attenuated in mammals may be a prelude to the generation of a pandemic strain."

They add that because H5N1 infections in swine increase the risk that a pandemic strain could emerge, the findings point up the need for "continuous surveillance and management of H5N1 viruses in pigs."

A good public reminder that surveillance is key to predicting and preventing a pandemic.

For the full article: http://www.cidrap.umn.edu/cidrap/content/influenza/avianflu/news/mar3109swine-jw.html