Russian lab worker's suspected plague death leaves experts puzzled

The unexplained death of a lab technician at a Russian research institute handling plague bacteria has raised questions among infectious disease experts, who say the circumstances surrounding the case are unusual and key details remain unanswered.According to local reports, some 200 people have been put under medical observation, or quarantined, in the Siberian area of Irkutsk. Other reports say an incident in the lab dealing with the bacteria preceded the fatality. CNBC has not been able to independently verify these reports.Russia told the World Health Organization on Tuesday that no cases of plague had been recorded in Irkutsk, according to a WHO spokesperson. It wasn't immediately clear if that included the diseased lab worker. While the WHO and health authorities around the world say the risk of a wider outbreak appears low, experts told CNBC that the reported circumstances of the death are difficult to reconcile with the stringent safeguards normally used when working with the deadly pathogen.Javier Pizarro-Cerda, head of the Yersinia Research Unit at the Institut Pasteur in Paris, told CNBC he was "very surprised" by the report coming out of Russia, since people working with...