Safety fears raised over biosecurity lapse

By Jeff Hecht and Debora MacKenzie Three researchers at the Boston University Medical Center fell ill in 2004 after being exposed to a potentially deadly bacterium in a Level 2 biosecurity lab. Yet city and university officials kept the news quiet until after the centre’s application to build a more high-level biosecurity lab (Level 4) in a densely populated part of Boston was accepted by the city this January. University officials blamed careless procedures in their existing Level 2 lab, and say the researchers were studying a strain of the bacterium which causes tularaemia, also known as “rabbit fever”, but had thought the strain was harmless. A spokeswoman told New Scientist that the affected lab has been decontaminated, but tularaemia research has been stopped until staff members are retrained and a new manager appointed – the former head of the infectious disease section was removed from his post. Yet the incident raises warning flags about the proliferation of biodefence labs working with dangerous pathogens in the US, in the wake of the still-unsolved anthrax attacks of 2001. According to the Biosecurity Center of the University of Pittsburgh, US, federal funding for civilian biodefence research rose from $414 million in 2001 to an estimated $5.5 billion in 2004. The US also plans to build six new maximum containment biosecurity Level 4 (BSL4) labs, including the one in Boston, US, and 19 less-stringent BSL3 labs. A strikingly similar incident also occurred in 2004 when a new biodefence lab at Oakland Children’s Hospital in California, US, received live anthrax instead of dead germs, says Richard Ebright, a microbiologist at Rutgers University in Piscataway, New Jersey, US. The Oakland researchers did not spot the mix-up until all the animals died in their experiments. The hospital immediately called a press conference and abandoned biodefence research. Boston University has worked hard for the $128 million BSL4 lab, one of two funded by the US National Institute of Allergy and Infectious Disease, but it reacted slowly to the live-bacterium exposure in its BSL2 lab. In fact, no one suspected tularaemia when two lab workers fell ill in May, although one spent a night in the hospital. A third researcher was hospitalised in September 2004, but the illnesses were not linked to tularaemia until October. University officials say tests revealed their supposedly harmless tularaemia bacterium samples had been tainted with a virulent strain. However, the US Centers for Disease Control did not find the virulent strain when it analysed the bacterium from the Nebraska lab which supplied the original sample. Such a mix-up “would be impossible for any competently run microbiology laboratory”, Ebright told New Scientist. Standard procedures call for isolating one cell and its progeny to be sure that samples contain only a single strain. He thinks it unlikely that the harmless strain reverted to the virulent form, but says an active form could have been supplied by mistake. As in the Californian anthrax case, the samples were shipped without special precautions, he says. Tularaemia is extremely infectious – inhaling less than 10 bacteria can cause the disease. That makes it a potential biowarfare agent, although it is not as deadly or fast-developing as anthrax. City and university officials claimed the Boston incident was not a public health issue, because tularaemia is not transmitted between humans. And Boston mayor Tom Menino has been a vocal supporter of the new lab. But critics are sure to jump on sloppy procedures. Level 2 labs offer minimal security, requiring only an autoclave for sterilisation and a biosafety cabinet to hold hazardous materials. Yet the Boston workers did not do all their experiments in the biosafety cabinet. The lab also had little biodefence experience. Ebright says that neither the former head of the section, Peter Rice,
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