The Food and Agriculture Organisation (FAO) of the United Nations has warned India of a possible resurgence of the highly pathogenic H5N1 avian influenza (popularly known as bird flu).
FAO chief veterinary officer Juan Lubroth said in a report the government of six Asian countries including India, should focus on preparedness and surveillance to tackle the possible outbreak. There were signs that a mutant strain of the deadly virus, with unpredictable risks to human health, is spreading in Asia and beyond. Apart from India, FAO has rung the alarm bell for Bangladesh, China, Egypt, Indonesia and Vietnam.
In its first outbreak in 2003, millions of birds, mainly chickens, were culled and buried by poultry companies in India to control its spread among humans. The H5N1 virus has infected 565 people since it first appeared in 2003, killing 331 , according to figures compiled by the World Health Organisation (WHO). The latest death occurred earlier this month in Cambodia, which has registered eight cases of human infection this year, all of them fatal.
Since 2003, H5N1 has killed or forced the culling of 400 million domestic poultry and caused an estimated economic damage of $20 billion across the globe, before it was eliminated from most of the 63 countries infected at its peak in 2006.
However, the virus remained endemic in six nations, although the number of outbreaks in domestic poultry and wild bird populations shrank steadily from an annual peak of 4,000 to just 302 in mid 2008. But outbreaks have risen progressively since then, with almost 800 cases recorded in 2010-2011, FAO said.
At the same time, 2008 marked the beginning of renewed geographic expansion of the H5N1 virus, both in poultry and wild birds. The advance appears to be associated with migratory bird movements. Migrations help the virus travel over long distances. Thus, H5N1 has in the past 24 months affected poultry or wild birds in countries that had been virus-free for several years.