The World Health Organization fears that a global pandemic could occur should the H2N2 virus, the "Asian flu" strain of 1957, be unwittingly released, the virus which was mistakenly included in routine test kits and sent to 61 laboratories in 18 countries outside the United States.
Klaus Stohr, influenza chief of the World Health Organization says South Korea, Mexico and Lebanon have yet to destroy all samples of the killer influenza virus they received as part of test kits, but all three countries have made progress in tracing the missing shipments from the U.S.
WHO has been urging destruction of the 50-year-old H2N2 virus and believes that the matter will be resolved shortly.
Of the 3,747 kits distributed in October and February, U.S. laboratories received the vast majority and have destroyed more than 98 percent of them.
A sample that went astray in Lebanon had been handed over to another shipper for local delivery, it never arrived at the intended laboratory and authorities were now seeking to locate the kit.
A missing shipment to Mexico has been tracked down in a bonded warehouse, and is about to be destroyed. An attempt is being made to determine what happened to kits sent last year to three South Korean laboratories which they never received.
The H2N2 virus, 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.
Most of the samples were sent starting at the request of the College of American Pathologists, which helps labs test their ability to identify microbes.Stohr says it was extremely unwise and short-sighted and questions why a very pathogenic virus which can cause a pandemic be included in such proficiency testing. Once the H2N2 samples are destroyed, health authorities intend to look into tightening controls on the distribution of microbes.
Of concern is that, until health authorities raised the alarm over the testing kits two weeks ago, it was possible to buy H2N2 over the Internet.