Carson-Tahoe Hospital's laboratory on Wednesday morning destroyed two samples of a dangerous Asian flu strain, which the hospital accidentally received in January inside a kit used for proficiency testing.
Doris Dimmitt, the hospital's infection-control specialist, said Wednesday afternoon that the specimens were destroyed with a method of sterilization using heat and pressure and a chemical called Formalin.
"I've been in clinical microbiology for 22 years and nothing like this has ever happened before," she said.
Influenza A/H2N2, which triggered the 1957 Asian flu pandemic that killed from1 million to 4 million, was mistakenly sent to 4,000 labs, mostly in the United States.
An official with the College of American Pathologists said Meridian Bioscience, which is the vendor for the kits, knew it was sending a flu virus but did not realize it was the deadly Asian flu strain, according to Associated Press reports.
The World Health Organization urged labs late Tuesday to destroy the samples and then send a confirmation in writing.
"The specimen was sent to us by mistake to be worked up in the lab," Dimmitt said. "But any exposure or concern about infection would've been in January. Lab personnel could've caught this nasty strain of influenza."
Dimmitt said the kit is a competency test that certifies labs for antigen testing. Kits contain blind samples that labs must correctly identify to pass the test. The tests are overseen by the College of American Pathologists. Dimmitt said a lab technician here tested the subject vial and found that it was positive for influenza A. The two samples then sat in the hospital's storage refrigerator for about three months.
A Canadian laboratory had the capability to test further, which is how the sample was identified on March 26 as the deadly 1957 strain. It later traced the strain to a test kit, then reported to the WHO and the Centers for Disease Control and Prevention on April 8. Dimmitt said she learned about the mistake Wednesday morning.
The CDC requires the strain to be handled at a biosafety level of 3, which is a higher level of lab safety precautions. Carson-Tahoe Hospital's lab, and most labs in this area, operate at biosafety level 2.
Dimmitt said one lab staff member said she had the flu in January, but they are not sure it's related. The strain would've stayed alive in the environment for only one or two days, she said.
"When you work in a lab you are aware of the risks. Microbiologists are very meticulous. We all take precautions. I think that's why nothing happened with this."
The CDC reported that there had been no sign of the flu strain circulating. The WHO also reported that there have been no reports of H2N2 infections in laboratory workers associated with the distribution of the kit samples.
Labs in 17 other countries, including South Korea, Saudi Arabia and Lebanon also received the kits with the strain. The WHO reported many of those countries had announced that they had destroyed all their samples.
Washoe Medical Center spokeswoman Judy Davis said its lab did not receive the dangerous flu strain.
n With AP reports. Contact reporter Becky Bosshart at bbosshart@nevadaappeal.com or 881-1212.
