Following an investigation of avian flu cases in Vietnam, the World Health Organization yesterday said it found no evidence that the virus had mutated in ways that would make it more easily transmitted among humans.
So far, scientists have documented just one case of the virus spreading from human to human - a chain of transmission among a family in Thailand. But many have warned that a simple genetic change could enable the virus to spread more efficiently among humans, touching off a pandemic that could put millions of people at risk worldwide.
At the request of the Vietnamese health ministry, the WHO dispatched an international team of experts to that nation last week to see if the agency should issue a heightened pandemic alert. After reviewing laboratory evidence and case studies, the team said it found no grounds for that.
"While these first results are reassuring, further retesting of clinical specimens will continue over the next few weeks to provide the most reliable possible foundation for risk assessment," the agency said yesterday in a prepared statement.
Vietnam has reported the largest number of human fatalities to avian flu in the region. Yesterday, the country reported its 39th case, bringing the total in Southeast Asia to 55.
The victim was a 72-year-old man from Hanoi who died Tuesday after being admitted to Bach May Hospital six days earlier, said a hospital spokesman.
Another 12 people have died in Thailand and four in Cambodia.
Meanwhile, Vietnam said Wednesday it would begin in August to vaccinate poultry against bird flu. The vaccinations will begin at commercial poultry installations and smaller family farms in two provinces, one in the north and the other in the south along the Mekong Delta, the Associated Press reported.
Vaccinations will then be expanded to another 40 high-risk provinces over the next two years. An initial 20 million doses will be imported from the Netherlands and China.