A killer flu virus, sent to laboratories around the world as part of routine test kits, could trigger a pandemic if it escapes and health experts have called for the potentially lethal samples to be destroyed.
Senior World Health Organisation (WHO) scientist Dr Klaus Stohr said the virus, which killed between 1 million and 4 million people in 1957, had been sent to about 3,700 laboratories, nearly all in the United States.
"The virus could cause a global (flu) outbreak. It was an unwise decision to send it out," said Stohr, who heads the United Nations health agency's influenza programme. But the laboratories, which are sent viruses to test their ability to detect strains, are experienced in handling such material and most had already been alerted to the danger, so there was little chance of anyone catching it, he added. "It is a risk, but it is considered low. It should not lead to a big scare," Dr Stohr said.
The US concern that sent out the virus, the College of American Pathologists (CAP), has issued instructions for all samples to be destroyed and would report to the WHO and US health authorities by Friday on the response, he said.
"By Friday we may be through with this," Dr Stohr said. The latest alert comes as the WHO is already sounding the alarm over influenza because it fears that a continuing outbreak of bird flu in Asia, if not contained, could eventually trigger a human pandemic.
The 1957 virus has not been used in anti-flu vaccines since 1968, meaning anyone born after that date would carry no immunity to the bug. It went to some 61 laboratories outside North America, all of which had been contacted, Dr Stohr said.
Agencies