GENEVA, April 18 (Xinhuanet) -- All labs that received samples of a fatal flu virus in test kits, except for those in the United States, have destroyed the virus, the World Health Organization (WHO) said on Monday.

    The destruction of the virus samples is still ongoing in the United States, and is expected to be completed shortly, the United Nations health agency said in a statement.

    The WHO statement criticized the College of American Pathologist in the United States for sending the virus as "unwise",saying that the virus could trigger a pandemic if it escaped from the labs.

    So far, more than 3,700 labs in 18 countries and areas have received samples of the H2N2 virus, which killed between one and four million people in 1957-58 in Asia, as part of routine testing of labs' ability to detect strains.

    A week ago, the agency asked all labs to destroy the virus.

    There has been no report of infection by the virus this time, according to the WHO. Enditem