Taiwan can be added to the growing list of recent HPAI (highly pathogenic avian influenza) outbreaks in poultry, with word this morning that a large egg farm in Pingtung County – in the far south of the island – has begun culling more than 120,000 birds after the H5N2 virus was confirmed.
First, this brief notice from Hong Kong’s government:
January 9, 2015
Taiwan authorities announced the outbreak of highly pathogenic H5N2 in Pingtung County subtype of avian influenza, CFS announced immediate entrance to the county's ban eggs.
It should be because of bird flu, the center in November 2012, August 2013 and December last year, has announced a ban on Taiwan and Penghu, Hualien and Ilan egg import ban is still in force.
Centre will closely monitor the OIE news about bird flu outbreak in Taiwan, to act according to the local epidemic.
Meanwhile Taiwan's Central News Agency (Focus Taiwan) is reporting:
Taipei, Jan. 9 (CNA) All of the 120,000 chickens on a farm in Pingtung County will be culled after some have been confirmed infected with highly-pathogenic H5N2 avian influenza, the county government said Friday.
Reports suggest that this outbreak may have begun sometime in December, and that eggs have been shipped from the farm after the virus emerged. Once cooked, however, the virus would be deactivated.
HPAI H5N2 is believed to pose very little risk to human health, although those with long memories will recall that we’ve seen a small number of seroprevalence studies that have found elevated H5N2 antibody titers – particularly among poultry workers.
J Epidemiol. 2008;18(4):160-6. Epub 2008 Jul 7.
Human H5N2 avian influenza infection in Japan and the factors associated with high H5N2-neutralizing antibody titer.
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.
Yamazaki Y, Doy M, Okabe N, Yasui Y, Nakashima K, Fujieda T, Yamato S, Kawata Y, Ogata T.
While suggestive of (possibly sub-clinical) prior H5N2 infection (note: other factors might be associated antibody positivity), there is precious little evidence to link any significant or serious human illness to the H5N2 virus. After an earlier HPAI H5N2 outbreak in Taiwan back in 2012 we saw assurances from the WHO: Human Risk From H5N2 Is Low.
Of course, the caveat holds that influenza viruses are constantly changing. What was true last year, or even last week, may not hold true forever.
But for now, much like the HPAI H5N8 virus, H5N2 is viewed as primarily a threat to birds, and not to humans.