A Russian official on Thursday sought to turn the page on the suspicious death of a worker at a plague research lab in Siberia, saying a quarantine and other preventive measures had been completed with no dangerous pathogens detected.

The statement by Irkutsk Gov. Igor Kobzev came a day after the World Health Organization requested more information from Russia about the death of the worker at the Irkutsk Anti-Plague Institute of Siberia that sparked global concerns about a possible case of pneumonic plague.

Media reports in Russia blamed the Oct. 2 death of the woman, whom news outlets identified as Darya Shipilova, 28, on pneumonic plague, which can spread from person to person.