Siberian plague researcher dies from unknown cause, hospital quarantined

Russia quarantined an entire hospital in Siberia after a researcher at a plague institute died from unknown causes, sparking fears the disease may be spreading. The woman died last week from pneumonia of "unknown" origin, though authorities found no evidence linking her death to pathogens she worked with. The researcher worked at the Irkutsk Anti-Plague Institute in southeastern Siberia. The hospital in Shelekhov stopped admitting and discharging patients, while health agents are monitoring her contacts. Unconfirmed media reports suggested she may have died of pneumonic plague, a rare but severe form transmissible person-to-person. US Secretary of State Marco Rubio said the case is being closely watched, while the Kremlin urged the public to rely on official statements. The World Health Organization describes pneumonic plague as a serious form of the disease caused by Yersinia pestis bacteria.