WHO: Bird flu virus unpredictable
Associated Press | June 10, 2005
By Audra Ang
BEIJING (AP) — A top World Health Organization official warned Friday that the avian flu virus is evolving quickly and urged heightened vigilance because the strain in China appears to have increased in virulence.
“The virus remains unstable, unpredictable and very versatile,” Shigeru Omi, the WHO’s Western Pacific regional director, said at a news conference.
“Anything could happen,” he said. “Judging from the way the virus has behaved it may have new and unpleasant surprises in store for us.”
Omi said the H5N1 virus is behaving differently in China and Vietnam. China has reported no human cases of bird flu while Vietnam has had 38 of Asia’s 54 human deaths.
But the cases in Vietnam appear to be becoming less deadly, with fatality rates dropping from a high of 60 to 70 per cent last year, to about 10 to 20 per cent so far in 2005, Omi said.
Vietnam has also seen more asymptomatic cases, where people are infected but don’t develop symptoms.
In China, however, two outbreaks among birds in the country’s remote west in the past month have killed large numbers of different species of birds which had previously been relatively resilient to the disease, Omi said.
“The outbreaks indicate that the virus has become highly pathogenic to more and more species,” he said.
The different paths H5N1 has taken in China and Vietnam shows that it “is evolving very quickly,” he said.
The only way to safeguard against further outbreaks or worse — a mutation of the virus into a form easily passed between humans — is “heightened vigilance,” he said.
“Our work remains urgent,” Omi said.
That means it’s imperative for countries to share information, research and samples from their outbreaks with international agencies to strengthen efforts to fight the disease, he said.
Countries also need to strengthen their pandemic preparation plans, which include improved vaccine development and making anti-viral drugs available, Omi said.
Beijing has in the past been criticized for its reluctance to release information on its outbreaks.
Omi said the WHO is looking forward to getting samples from China because “sharing samples is very critical.”
WHO officials said they were waiting for Beijing to approve a trip with Chinese health officials to Qinghai province, where more than 1,000 wild birds, including geese and gulls, were killed by the H5N1 flu strain in late May.
On Thursday, the Agriculture Ministry confirmed a second outbreak of bird flu in the Xinjiang region.
It said it had culled more than 13,000 geese at a farm after discovering that about 460 had died from the virus.
China said both outbreaks appeared to be isolated incidents, with the case in Qinghai possibly carried there by migrating birds.
Omi and other health experts were in Beijing for a three-day conference on eliminating and controlling measles and hepatitis B in the region.
The panel agreed on a target to eliminate measles by 2012 and have less than two per cent of chronic hepatitis infection in children under five the same year.
There are now 160 million chronic carriers of hepatitis B in the region, with 120 million of them in China.