Marco Rubio Warns Russian Plague Outbreak Could 'Quickly Spread'—What It Means for You - Newsweek

The United States is closely monitoring reports surrounding the death of a worker at a Russian anti-plague laboratory, Secretary of State Marco Rubio said, warning that an infection could “quickly spread” if it “gets out.”

Russian authorities have not confirmed that pneumonic plague caused the woman’s death. The employee of the Irkutsk Anti-Plague Research Institute of Siberia and the Far East was hospitalized with severe pneumonia symptoms last Tuesday and died Thursday, according to The Moscow Times, which cited Russia’s public health watchdog as saying she had been diagnosed with “pneumonia of unknown etiology.”

The case has attracted international attention because the woman worked at a facility that handles dangerous pathogens and because media reports have identified pneumonic plague as the suspected infection.

Pneumonic plague affects the lungs and can spread between people through respiratory droplets, but Russian authorities have not confirmed that the worker had the disease.

The White House referred Newsweek to the State Department when reached for comment by email Monday.

In a statement emailed to Newsweek on Monday, a spokesperson from Health and Human Services (HHS), which oversees the Centers for Disease Control and Prevention (CDC), said: "CDC is monitoring the situation closely with the State Department and our other interagency partners. The safety and security of U.S. citizens is our highest priority."

"WHO is aware of reports that a laboratory worker in Irkutsk oblast, in the Russian Federation, died of severe pneumonia on 2 October 2026. To date, no cause of death has been officially confirmed, and laboratory testing is reportedly underway. All of the patient’s contacts have reportedly been identified and are being monitored for illness, and none to date have shown symptoms of illness," a World Health Organization (WHO) spokesperson told Newsweek in an emailed statement Monday.

"In accordance with Articles 9 and 10 of the International Health Regulations (2005) (IHR), WHO is in contact with the Russian health authorities to verify the event, its circumstances, the laboratory tests underway, and their results, the rationale for contact-tracing and the health status of contacts, as well as any potential international public health implication. WHO has offered support if needed," the spokesperson said, adding, "Based on unofficial information available, the public health risk to the general population appears to be low. The risk assessment will be updated once more information is available."

"Persons with pneumonic plague can spread the Y. pestis bacteria to other persons who can then develop pneumonia," Dr. Richard Martinello, the Yale Medicine chief medical officer who also serves as professor of medicine for infectious diseases and pediatrics, told Newsweek in an email Monday.

"This person-to-person spread is what makes pneumonic plague so problematic," Martinello warned.

Martinello told Newsweek in a phone interview Monday that while the transmission is concerning, the chances of the spread to the U.S. are minimal due to the location and tracking already in place by local health officials.

"The most important thing is what's already being done," he said. "They identified 200 people who were close contacts, and I would assume for all those close contacts that they are being carefully assessed. I wouldn't be surprised if you know many of them were offered antibiotics preemptively because this is so contagious.

"Beyond that, it would be very surprising to see this extend into a global issue."

Russian officials have said the regional health situation remains stable and that laboratory testing did not detect microorganisms associated with the employee’s work, The Moscow Times reported.

Rubio said that, based on the information released by Russia, it appeared that a laboratory worker had been infected and that authorities were concerned the illness might have spread internally.

“There's very limited travel between the U.S. and Russia, but like anything else, something like that gets out it could quickly spread,” Rubio warned.

“We know what we know, obviously, about whatever the Russians have provided, which is it seems that there was a worker at the lab that was infected,” Rubio told reporters on a tarmac Monday morning, adding, “and there's concern that that you know that could have spread at least internally.

“So you see them do quarantines of that nature,” he said.

“So we're watching and monitoring it closely. I don't think it's cause for alarm, but it is cause for focus and a cause to just keep an eye on it, and we're doing that,” he continued.

The female employee worked at the Irkutsk Anti-Plague Research Institute of Siberia and the Far East. She was hospitalized with symptoms of severe pneumonia before dying two days later, according to The Moscow Times.

Alexei Tsydenov, the head of the neighboring republic of Buryatia, initially said the employee had died of plague before modifying his statement to say she had “maybe” died of the disease, The Moscow Times reported.

Rospotrebnadzor, the Federal Service for the Oversight of Consumer Protection and Welfare in Russia, said laboratory analysis of material taken from the patient did not detect microorganisms associated with her work handling dangerous pathogens.

A special commission established by the institute and the health watchdog also concluded that no emergency or security breach had occurred, according to The Moscow Times, citing Interfax.

Earlier reports said the employee may have broken a test tube containing live bacteria. Russian authorities have not substantiated that account, and the commission examining the incident reported finding no laboratory emergency or security breach.

Rospotrebnadzor said the woman’s close contacts were placed under medical observation and underwent daily laboratory testing.

The testing detected two COVID-19 cases and two rhinovirus cases but no other infections, according to The Moscow Times. The watchdog also said no other infectious-disease complaints had been recorded among institute employees during the preceding 10 days.

Local media reported that hospitals in the region continued operating on standard schedules apart from localized precautions, contrary to earlier reports that facilities had been broadly closed.

Pneumonic plague is a lung infection caused by Yersinia pestis, the bacterium responsible for plague, Dr. Martinello explained. Unlike bubonic plague, which is commonly transmitted through the bites of infected fleas, pneumonic plague can spread between people through infectious respiratory droplets.

"The Yersinia pests bacteria can cause persons to develop pneumonia, sepsis, or skin/soft tissue infection which can progress to sepsis," Martinello explained, noting, "Pneumonic plague is when you have pneumonia due to the Y. pestis bacteria. It too can become complicated by sepsis."

Martinello said that people who have "pneumonic plague can spread the Y. pestis bacteria to other persons who can then develop pneumonia.

"This person-to-person spread is what makes pneumonic plague so problematic," he warned.

"There have been cases of pnuemonic plague before in India and elsewhere, and while that is a severe threat for that community, with good public health measures, this will this will come to a close, and hopefully, we don't see anybody else affected like the first individual," Martinello said in a phone interview Monday.

Symptoms can include fever, headache, weakness and rapidly developing pneumonia accompanied by shortness of breath, chest pain and coughing. Some patients may produce bloody or watery mucus.

The disease can develop when plague bacteria spread to the lungs from untreated bubonic or septicemic plague, or when someone inhales infectious droplets coughed out by an infected person or animal.

"Bubonic plague occurs in person who have skin/soft tissue infections with Y. Pestis," Martinello told Newsweek. "They develop abscesses of the lymph nodes typically by the site where they were bitten by the infected flea. This abscess is known as a bubo."

He noted that the U.S. sees about a half-dozen cases of bubonic plague a year, mostly in the Southwest and Four Corners region but said it is "very uncommon to see pneumonic [plague]."

Plague is treatable with antibiotics, particularly when treatment begins early. Pneumonic plague is considered especially serious because it can spread directly between people and progress rapidly without treatment.

Martinello said the most important thing is good public health practices, like the ones the US already has in place for flu, covid and other more common illnesses.

"Something that is so important here is the rapid identification," he explained, noting that the authorities in Russia have already identified about 200 close contacts of the original patient.

Russian authorities are continuing to monitor the woman’s close contacts and conduct testing. Irkutsk regional Governor Igor Kobzev said Monday that quarantined family members and close relatives could be discharged the following week, according to The Moscow Times.

The State Department and other federal agencies will continue monitoring the reports. For now, Russian authorities have not confirmed that plague caused the worker’s illness or identified evidence of a laboratory accident, while Rubio has said the situation is not a “cause for alarm” but warrants continued attention.

Newsweek’s reporters and editors used Martyn, our AI assistant, to produce this story. Learn more about Martyn here.

Contact Newsweek editors on this story: Jason Lemon and Gray R. Thomas