US Secretary of State Marco Rubio on 7 October 2026 said Washington and multiple international agencies are tracking a suspected plague case in Russia “hour by hour,” while pressing Moscow to share more information with the world. Rubio made the remarks during a joint press availability with Icelandic Foreign Minister Thorgerdur Katrin Gunnarsdottir in Reykjavik, as global concern mounted over a reportedly fatal suspected plague infection linked to a laboratory setting in Siberia.

What Rubio Said

Speaking cautiously, Rubio declined to speculate on whether the case could involve an accidental release of an intentionally modified pathogen strain. “It would be irresponsible for me here to sit and speculate because we just don’t have all the information yet,” he said. He acknowledged that laboratory-linked disease cases anywhere in the world are inherently cause for concern: “Any time you hear that there’s some disease that infected someone in a lab anywhere in the world, you’re going to be concerned about it.”

Rubio stressed that the United States had not yet reached any conclusion about the nature or severity of the incident. “Maybe, you know, there’s nothing there. Maybe it’s bigger than we thought. We don’t know,” he said, adding that the level of response would depend on what further information reveals.

Call for Russian Transparency

A central theme of Rubio’s remarks was the demand for openness from Russia. “I think it’s incumbent upon Russia to obviously share more information with the world. That’s what they should do. That’s what we hope they will do,” he said. He noted that greater transparency from Moscow would allow global health authorities to calibrate an appropriate response. This comes amid longstanding tensions between Washington and Moscow over information-sharing on biosecurity matters, a concern that gained international prominence during earlier disease outbreaks.

Measures Already in Place

Rubio indicated that the US is not waiting passively. “We already have measures in place to be able to address it if it’s something more serious than what so far has been acknowledged,” he said. He confirmed that “multiple agencies, not just in the United States but internationally” are involved in the monitoring effort. Notably, available information remained “quite limited” at the time of his remarks, though he expressed hope that would “change in the next few hours and days.”

Background and Context

Plague, caused by the bacterium Yersinia pestis, is considered one of the world’s most dangerous infectious diseases historically, though it is now treatable with antibiotics if caught early. Russia maintains extensive Soviet-era biological research infrastructure, and any suspected laboratory-linked case draws heightened international scrutiny. The incident in Siberia has not been officially confirmed or detailed by Russian authorities, which is itself a point of concern for Western governments. This is the latest in a series of episodes that have tested trust between Moscow and international public-health bodies.

What Happens Next

The international community, including US agencies and global health bodies, will continue monitoring developments closely. Rubio signalled that the nature of any formal response—diplomatic or otherwise—would be contingent on the information that emerges. “We’re watching it very closely, and I think the whole world is watching it very closely because depending on what we learn about it, we would know how to respond,” he said. All eyes are now on whether Moscow will provide the transparency that Washington and international partners are calling for.