Credit U.S. Fish and Wildlife Service
# 8216
And while we’ve been primarily concentrating on the H7N9 virus situation in China this morning, we’ve also this report from Korea on the testing of migratory birds for the H5N8 virus, and concerns that it may spread further.
This video report from Arirang News, after which I’ll return with a bit more.
As flocks of migratory birds make their way around Korea this winter, it seems they are both the carriers and the victims of the latest bird flu outbreak.
On Friday, local officials announced that more ducks had been found dead in a city closer to Seoul, in the central province of Chungcheongnam-do.
And.. further south in the nation's port city of Busan, officials are testing to see if a group of dead birds found there also tests positive for the latest H5N8 strain of bird flu.
As the birds' exact cause of death is being determined, officials have confirmed that still another group of ducks found dead in a river in Chungcheongnam-do Province was infected with the H5N8 strain of the AI virus.
This is the first confirmation that AI has spread to other regions in the country.
For now, we’ve no evidence to suggest this H5N8 virus poses a substantial risk to human health, although our experience with its more famous avian cousin – H5N1 – certainly dictates caution.
Other H5 avian viruses, such as H5N2, have only demonstrated a very limited ability to infect humans.
Eighteen months ago, in Taiwan: Three Poultry Workers Show H5N2 Antibodies, we looked at a report that three poultry workers and officials working in animal quarantine have tested positive for antibodies for the H5N2, but all remained healthy and asymptomatic (note: refer to article for other possible causes of seropositivity).
Some earlier H5N2 studies suggestive of prior H5N2 human infection – particularly among poultry workers – include:
J Epidemiol. 2008;18(4):160-6. Epub 2008 Jul 7.
Ogata T, Yamazaki Y, Okabe N, Nakamura Y, Tashiro M, Nagata N, Itamura S, Yasui Y, Nakashima K, Doi M, Izumi Y, Fujieda T, Yamato S, Kawada Y.
Arch Virol. 2009;154(3):421-7. Epub 2009 Feb 3.
Serological survey of avian H5N2-subtype influenza virus infections in human populations.Yamazaki Y, Doy M, Okabe N, Yasui Y, Nakashima K, Fujieda T, Yamato S, Kawata Y, Ogata T.
Still, we haven’t seen any good evidence that H5N2 has produced significant or serious human illness.
The caveat being, that up until the emergence of H7N9 in March of this year, H7 avian flu viruses had been generally regarded as posing a minor threat to human health as well.
Which, when you combine it with the massive economic losses to the poultry industry, makes the rapid and intense response to bird flu outbreaks – such as we are seeing with H5N8 in South Korea right now – the prudent course of action.
