Flaws detected after TB infects 3 at Seattle lab

Three workers in a downtown Seattle research laboratory were infected with tuberculosis while working on a vaccine for the deadly disease, state officials say.

The accident at the Infectious Disease Research Institute occurred when researchers were infecting guinea pigs in a small chamber containing aerosolized TB bacteria, according to institute officials and the state Department of Labor and Industries (L&I).

None of the workers — a researcher and two technicians — has active TB. All were treated with a preventive drug for six to nine months after the infections were discovered last year during routine TB testing.

"There was no hazard to anyone outside" the tightly controlled level 3 lab, said John Furman, occupational-nurse consultant for L&I. The lab is housed in space leased by Corixa, a biotech company, at 1124 Columbia St.

Biosafety level 3 laboratories are one step below those authorized to handle the most dangerous pathogens.

The Infectious Disease Research Institute (IDRI) is a small, nonprofit organization that sometimes collaborates with Corixa and other companies. It is supported by the National Institutes of Health and private donations and works on vaccines and diagnostic tests for a variety of diseases.

No one knows for certain how the workers were infected. But an extensive L&I investigation found there were leaks in the infection chamber, workers didn't wear sufficiently protective masks and there was no written protection program for working with TB.

IDRI was fined $2,000 for violations of state regulations. The company corrected the deficiencies and increased safety precautions, L&I officials said.

The accident was revealed in a Web site posting this month by the Sunshine Project, a small Texas- and Germany-based nonprofit that watchdogs biodefense programs.

News of the exposures comes as the University of Washington is being criticized for its proposal to build a biodefense and infectious-disease laboratory near Portage Bay. The facility also would be a level 3 lab, for studying lethal airborne agents and other diseases.

Area residents and UW faculty members have questioned why it should be built in Seattle. Federal officials will announce in September whether the UW's application for $25 million to build the facility is approved. It will then have to raise at least an additional $20 million for construction.

Referring to the IDRI incident, Albert Berger, UW vice dean for research, said the highest risk in such facilities is always to those who work with infectious agents.

"The UW is seeking community input while at the same time educating the public about the safety and security measures that will be part of the building," he said in a written statement. "Level 2 and 3 research is currently being conducted at sites throughout the UW as well as at other research facilities in Seattle."

L&I learned of the IDRI infections only when the three workers filed workers'-compensation claims to cover medical expenses. The agency's claims division notifies its inspection division about any cluster of three or more illnesses from one location, said Furman, of L&I.

Health officials said no state or federal laws required reporting of the lab accident because it was in a research lab, rather than a clinical lab. TB kills about 2 million people a year worldwide, but it must be reported to public-health officials only when the patient has an active case, causing serious illness, and is contagious.

"We didn't report it because we thought it was an automatic report from the claims the workers filed," said David Webster, chief of operations for IDRI. "We weren't trying to hide anything."

L&I and IDRI reported the incident to the University of Wisconsin, which makes the Madison chamber, as it is called. But officials there said they didn't think it necessary to alert any of the other 15 to 25 institutions using the chamber. The chamber operates with a vacuum, so no germs should get out, said Todd Kile, shops manager for the University of Wisconsin's College of Engineering.

Kile believes the workers were infected because they weren't wearing sufficiently protective masks when handling the infected animals. "We don't feel there was a fault in the design or construction of the chamber," he said.

L&I faulted IDRI for not testing the chamber for leaks before using it, beginning in December 2003. After the infections were confirmed in March 2004, tests showed that the chamber, under positive pressure, leaked from tubing and from a nebulizer used to aerosolize a broth containing TB bacteria. Two O-ring gaskets on the nebulizer had deteriorated, officials said.

Webster, of IDRI, said officials at other labs using the chamber had told him there had been no problems, "so we saw no need to go over it."

Researchers at Colorado State University have since tested their chamber with a saline solution and found a leak. No one has been infected, said Ian Orme, a professor of microbiology.

Webster said the chamber at IDRI is now tested for leaks before and after each use, about once every three months.

At least one institution that plans to use the Madison chamber to research biological-warfare agents had not heard of the IDRI accident. "That's a real problem. There needs to be some mechanism that informs us," said Dr. Thomas Ficht, professor of veterinary pathobiology at Texas A&M University in College Station, Texas. Ficht plans to use the chamber in researching brucellosis and Q fever, caused by potentially deadly bacteria that could be used in biological warfare.

L&I also faulted IDRI for not making sure respirators worn by the employees fit properly. But Webster said he was assured when he bought the chamber that respirators weren't needed because the chamber operates under a vacuum. He said he doesn't remember who told him that.

Webster and Dr. Rhea Coler, lead researcher, said workers now are required to wear powered respirators that force air out of the mask, rather than the fiber, surgical-type masks they previously used. They said a protection program for workers is now in writing and each worker is required to undergo a medical evaluation before using the new respirators.

The institute also recently installed a separate "Biobubble" to contain the infection chamber, all of which is in the level 3 laboratory. The lab, within the locked facility, is guarded by two sets of locked doors. It is also under negative air pressure, so air will flow in, rather than out.

Warren King: 206-464-2247 or wking@seattletimes.com

Times researcher David Turim contributed.