Rush to destroy deadly flu virus samples

Thousands of scientists in 18 countries are being urged to destroy potentially lethal influenza samples sent out in routine testing kits.

The US Government has warned that vials of a 1957 strain which killed up to four million people were sent to nearly 5000 labs, mostly in the US.

The World Health Organisation said there was a slim but real risk the samples could spark a global flu epidemic if they infected anyone.

The strain of the virus has not been in circulation since 1968, and those born after that date do not have antibodies to fight it. It is not immediately clear why the strain was in the proficiency kits, which labs use in quality control tests to identify viruses.

WHO's influenza chief, Klaus Stohr, said the decision was "unwise" and "unfortunate".

Almost 99 per cent of the labs that got the test kits are in the US, Stohr said. Fourteen are in Canada and 61 samples went to labs in 16 other countries in Europe, Asia, the Middle East and South America.

New Zealand did not receive kits containing the potentially lethal virus.