The World Health Organisation issued a warning yesterday after a US institute sent to thousands of laboratories samples of a lethal flu virus that killed up to four million people in the late 1950s.The controversy revealed an apparent loophole in biosafety procedures, as the WHO and national health authorities ordered the labs to destroy the samples.
"There is a slim, but a real risk that this could spark a pandemic," said Maria Cheng, a spokeswoman for the WHO, explaining that many people around the world would have no protection if the virus were ever released from the high-security labs.
The virus, PN2, killed between one million and four million people worldwide during the Asian influenza pandemic of 1957-58 before disappearing in 1968.
"As far as pandemics go, it (the event in 1957-58) was relatively mild. But if this were to recur, it would have significant consequences for the public health system," Cheng said.
The samples were included in kits used to regularly test the ability of the laboratories in 18 countries to identify strains of flu virus.
Ninety per cent of the laboratories were in North America.
US President George W Bush considered the destruction of the virus samples as a "high priority", a White House spokesman Scott McLellan said in Washington, while playing down the risk to the public.
The virus was sent to laboratories in Belgium, Bermuda, Brazil, Canada, Chile, France, Germany, Hong Kong, Israel, Italy, Japan, Lebanon, Mexico, Saudi Arabia, Singapore, South Korea, Taiwan and the United States, the UN's health agency said.
So far, laboratories in Canada, Hong Kong, Singapore and South Korea were known to have destroyed all the PN2 samples they received, it said.
The agency's top flu expert, Klaus Stohr, said all the samples were expected to be destroyed by tomorrow after the "short-sighted" distribution.
"We are certainly also a little bit fortunate here that things have not gone worse," he added, while praising the skill and response of lab workers and authorities.
A US-based private institution, the College of American Pathologists, distributed the samples of PN2 to 3,747 laboratories through the private Meridian Bioscience Inc in two batches, in October last and February this year.
The samples appeared to have been distributed deliberately and legally because of national differences in the hazard rating of the strain, Stohr told journalists.
PHOTO CAPTION
A worker feeds chickens at a private farm in Hoc Mon district on the outskirts of Ho Chi Minh-City. (AFP)