(ROME) -- A new strain of avian H5N1 influenza, also known as bird flu, has surfaced, the Food and Agriculture Organization (FAO) said Monday. The vaccine-resistant viral strain has shown up in flocks of poultry in both China and Vietnam, the FAO said, according to MedPage Today.
"In Vietnam, which suspended its springtime poultry vaccination campaign this year, most of the northern and central parts of the country -- where H5N1 is endemic -- have been invaded by the new virus strain, known as H5N1-188.8.131.52," FAO cautioned in a statement Monday.
While cases of human infection have not been reported, according to the World Health Organization, the FAO warned that spread of the strain could present "unpredictable risks to human health," MedPage Today reports.
Cases of the bird flu epidemic were cut down in 2008 after countries impacted by the virus slaughtered scores of afflicted poultry flocks. But new flare-ups surfaced, causing numbers of cases to jump to almost 800 in January 2010 from 300 in 2008, Medpage reports.
Now virus-stricken poultry cases have been reported in Bulgaria, Romania, Palestinian territories and Israel.
Human bird flu cases amount to 565 globally, with 331 deaths since 2003, according to the WHO.
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