The bird flu strain that killed 24 people in east Asia this year and resurfaced in recent weeks has become endemic to the region, and the virus could trigger a global health crisis if it goes unchecked, a new study says.
The World Health Organization said Thursday that the study suggests the virus is more widespread than previously thought and therefore will be harder to eliminate. The WHO urged governments in the region to share virus samples from recent outbreaks with WHO laboratories so the disease can be effectively monitored.
In the study, published by the London-based science journal Nature, researchers led by a Hong Kong microbiologist found that domestic ducks in southern China played a key role in creation of the H5N1 flu virus, while wild birds probably helped spread it through Asia.
Early this year, the virus raged through Asia’s poultry farms, and jumped to humans in cases that were mostly traced to direct contact with sick birds, killing 16 people in Vietnam and eight in Thailand. Health officials raised concerns about the illness mutating into a strain that could easily be passed among humans, but said there was no sign that had happened.
New outbreaks from the same deadly strain re-emerged in eastern China and two Thai provinces this week, and officials began slaughtering thousands of chickens to halt its spread. Vietnam also has reported bird flu outbreaks in recent weeks.
Virus is rapidly mutating
The researchers found that the bird flu strain earlier this year had evolved from one that crossed over to humans and killed six people in Hong Kong in 1997.
Guan Yi, the University of Hong Kong microbiologist who led the research, told The Associated Press on Thursday that the virus is rapidly mutating, and chances are high it eventually will be able to jump from human to human.
“We already know that it can kill humans,” he said. If it becomes human-to-human transmission occurs, Guan said, “then a pandemic would happen.”
Guan said the scientists have reported their findings to the WHO and the U.S. Centers for Disease Control and Prevention. He urged governments in the region to take prompt measures to contain bird flu outbreaks, including developing a vaccine and diagnostic test for the virus.