US urges Russia to disclose details of suspected plague pathogen leak at Irkutsk lab

The Trump administration has called on Russia to disclose more information about a suspected plague pathogen leak at a research institute in Irkutsk, saying it cannot determine its response because information is limited. US Secretary of State Marco Rubio told a press conference in Iceland on October 6 that it would be irresponsible to speculate without all the facts, and that Russia “clearly has an obligation” to share more with the world, Yonhap and Asia Economy reported. [ 4 , 6 ]

Rubio said that the more is known about what happened, the better the response can be, adding that “maybe it is nothing, maybe it is a bigger problem than we thought.” He said measures are already in place if the situation is more serious than what is known so far, and that the United States is watching the situation “hour by hour.” He said he hoped the situation would change within hours or days, and that the day before he had said the matter was not something to be anxious about but something to keep watching, according to the two reports. [ 4 , 6 ]

The incident occurred on September 25, when a female researcher at the Irkutsk plague control research institute broke a test tube containing plague pathogen. She was hospitalised on September 29 with severe pneumonia symptoms and died between October 1 and 2. Local media reported that about 200 people at the hospital where she was taken were designated for quarantine observation, and that a maternity hospital in the city was also placed under quarantine, Yonhap and Asia Economy reported. [ 4 , 6 ]

According to the Washington Post, cited by Yonhap, US officials have warned that much about the incident is unknown, and the Centers for Disease Control and Prevention, the State Department and the Administration for Strategic Preparedness and Response are among the agencies trying to understand it. Current and former US officials want to know whether the institute used “gain-of-function” techniques to make plague samples more infectious or more resistant to drugs. Ashish Jha, who led the Biden administration's COVID-19 response, told the Post that unconfirmed reports of Russian security agencies being involved in transporting the researcher to hospital were “concerning,” and said Russia is known to run an offensive biological weapons programme. [ 4 ]

Axios said it is important to establish whether the incident arose from legitimate Russian plague research or from a biological weapons development programme. There is currently no evidence that the researcher was involved in weaponised or genetically modified bacteria research, and some reports say she had recently visited the Russia-Mongolia border region, where plague occurs naturally in animals. Axios also noted that the James Martin Center for Nonproliferation Studies has pointed out that the institute developed vaccines and diagnostics against pathogens modified by Russian military authorities, and that the US State Department assessed in 2024 that Russia maintains an offensive biological weapons programme. [ 4 , 6 ]

According to Axios, US authorities lack information on the cause of the researcher's illness and death and on how well any spread has been contained, making it difficult to judge how serious the plague threat is and whether travel alerts, US entry restrictions or other precautions are needed. The Trump administration is holding off on a government-level response in the meantime. [ 4 ]

Korean outlets began covering the story on the evening of October 6. Kukmin Ilbo reported the suspected leak and, later, the US call for disclosure, saying some suspect a biological weapon; Newsis led on the Secretary of State's demand; Asia Economy carried the incident details and Rubio's remarks. Yonhap, the national news agency, provided the fullest account. [ 1 , 2 , 4 , 5 , 6 ]