Sunday, August 22, 2010

Of Ducks, And Feathers, And H5N1



# 4826



Ducks and other aquatic birds  are a major reservoir of the H5N1 virus, with some species capable of carrying the pathogen without ill effect.  H5N1 is generally a gastrointestinal malady in birds, and the belief is that the virus is usually spread via infected feces.


In 2006, however, we became aware of a cluster of human H5N1 infections (7 cases, 4 fatalities) in Azerbaijan which were ultimately linked to the harvesting of feathers from dead swans.



And more recently, in June of this year, we saw a study (see Birds Of A Feather . . . .) in PLoS One, suggesting that waterfowl may be acquiring and spreading avian flu viruses because their preening oils bind the virus to their feathers.

Can Preening Contribute to Influenza A Virus Infection in Wild Waterbirds?

Mauro Delogu, Maria A. De Marco, Livia Di Trani, Elisabetta Raffini, Claudia Cotti, Simona Puzelli, Fabio Ostanello, Robert G. Webster, Antonio Cassone, Isabella Donatelli



So the findings  of today’s study, which was conducted by researchers at the  National Institute of Animal Health, Tsukuba, Ibaraki, Japan  and reported in the August issue of Applied and Environmental Microbiology shouldn’t come as a complete surprise.


They determined that the H5N1 virus may persist on the dropped feathers from infected ducks and that they may spread the virus to the environment.  You can follow the link below to read the abstract.


Applied and Environmental Microbiology, August 2010, p. 5496-5499, Vol. 76, No. 16
0099-2240/10/$12.00+0     doi:10.1128/AEM.00563-10

Persistence of Avian Influenza Virus (H5N1) in Feathers Detached from Bodies of Infected Domestic Ducks

Yu Yamamoto, Kikuyasu Nakamura, Manabu Yamada, and Masaji Mase


The surprising part of this study is how long these feathers retained some degree of viral contamination at various temperatures.


At 4°C (39F) the virus was detectable for 160 days, while at the higher temperature 20°C (68F), the virus was detected for 15 days.


While these results were obtained under laboratory conditions, and these impressive durations might not be equaled in the wild, this research does suggest that feathers could be a possible vector of the bird flu virus to other birds, to mammals, and to the environment.

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