Scientists Scramble to Destroy Flu Strain
Killer Virus Sent to Thousands of Laboratories

April 13) - Scientists around the world were scrambling to prevent the possibility of a pandemic after a nearly 50-year-old killer influenza virus was sent to thousands of labs, a decision that one researcher described as ''unwise.''

Nearly 5,000 labs in 18 countries, mostly in the United States, were urged by the World Health Organization to destroy samples of the dangerous virus because of the slight risk it could trigger a global outbreak. The labs received the virus from a U.S. company that supplies kits used for quality control tests.

''The risk is low and we've taken appropriate action,'' said Dr. Nancy Cox, chief of the influenza branch at the Centers for Disease Control and Prevention in Atlanta.

Her counterpart at WHO, Klaus Stohr, agreed but said, ''If someone does get infected, the risk of severe illness is high, and this virus has shown to be fully transmissible.''

The germ, the 1957 H2N2 ''Asian flu'' strain, killed between 1 million and 4 million people. It has not been included in flu vaccines since 1968, and anyone born after that date has little or no immunity to it.

The WHO said Tuesday that there have been no reports of infections in laboratory workers associated with the distribution of the samples and that ''the risk for the general population is also considered low.''

Still, the decision to send out the strain was described by Stohr as ''unwise'' and ''unfortunate.''

The CDC learned Friday that test kits prepared by Meridian Bioscience Inc. of Cincinnati contained the virus. The company makes kits for at least four groups that help labs do proficiency testing, which involves identifying viruses to check a lab's quality controls or to acquire certification.

The largest of those groups, the College of American Pathologists, said it had sent 3,747 kits to various labs starting last year and ending in February.

Dr. Jared Schwartz, an official with the pathology college, said Meridian was told to pick an influenza sample and chose from its stockpile the deadly 1957 strain, which it had received from a ''germ library'' in 2000.

Other test kit providers also used the strain. Schwartz identified them as Medical Lab Evaluators, the American Association of Bioanalysts and the American Association of Family Practitioners.

Officials at Meridian could not immediately be reached for comment late Tuesday after business hours.

Most of the labs that received the test kits were in the United States. The vials also were sent to labs in Belgium, Bermuda, Canada, Chile, Brazil, France, Germany, Chile, Hong Kong, Israel, Italy, Lebanon, Mexico, South Korea, Saudi Arabia, Singapore and Taiwan.

Some of the labs outside the United States have already incinerated their samples, Stohr said, and WHO hoped the rest of the vials would be destroyed by Friday.

The kits contain blind samples that labs must correctly identify to pass the test. The influenza virus included in the kits typically is one that is currently circulating or has recently circulated.

A Canadian laboratory detected the 1957 pandemic strain on March 26 in a sample that was later traced to a test kit.

The WHO notified health authorities in countries that received the kits and recommended that all samples be destroyed. The College of American Pathologists asked labs to incinerate the samples immediately and confirm their actions in writing.

The virus' presence in thousands of labs focused fresh attention on the safe handling of deadly germs - an issue that led to toughened U.S. rules after anthrax was sent in the mail in 2001, killing five Americans.

Cox said officials strongly doubt someone deliberately planted the dangerous germ. ''It wouldn't be a smart way to start a pandemic to send it to laboratories because we have people well trained in biocontainment,'' she said.

But Stohr said the test kits are not the only supplies of the 1957 pandemic strain sitting in laboratories around the world. ''The world really has to think what routine labs should be doing with these samples they have kept in the back of their fridges,'' he said.