Bird flu has raised its ugly head again and is spreading quickly throughout most of Asia and beyond. Cases have been confirmed by the WHO in Hong Kong, North East India, Cambodia, Vietnam and Indonesia, while South Korea and Thailand have been put on high alert. According to the Wall Street Journal, Indian authorities in the North eastern state of Assam said they would cull 200,000 chickens while Hong Kong authorities have already quarantined a chicken farm and culled 80,000 birds. In Indonesia, two deaths by avian influenza were confirmed while in Cambodia, a 19 year old girl is known to have caught the H5N1 virus.
The spread and massive outbreak of the avian virus five years after it created havoc across south east Asia begs the question of effectiveness of the vaccines. Even though the spread of viruses are amplified when the weather changes – around this time, many experts believe that poultry farms are using vaccines that don’t provide full protection against the H5N1 virus or its mutations, leaving millions vulnerable.
“The virus is definitely mutating,” Guan Yi, an expert on the H5N1 virus at the University of Hong Kong told Reuters, warning that in some areas authorities were using batches of vaccine that were no longer effective.
What makes curbing the virus even more difficult is its various strains and its speed of mutation across the world. Vaccines used in order to be effective need to counter the exact virus they were built to fight. If used against a mutated strain of the H5N1, it will be ineffective.
Since 1997, when H5N1 was first identified in people in Hong Kong, scientists have discovered 10 clades, or branches, of the H5N1, which shows the speed and extent at which it is mutating.
The strain that is circulating in Indonesia, for example, is very different from the H5N1 strain that has been making the rounds in Europe, the Middle East and Africa, which experts say was brought to those parts by migratory birds after picking up the virus in China’s Qinghai Lake, Reuters continued.
The H5N1 virus has infected 391 people in 15 countries since 2003, killing 246 of them.
