“I think it’s incumbent upon Russia to obviously share more information with the world,” Rubio told reporters, as quoted by the BBC. “We’re watching it very closely, hour by hour.”

Speaking about the incident, Rubio said, “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, and there’s concern that that could have spread, at least internally.”

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He added that Russian authorities had imposed quarantines in response to the incident.

“You’ve seen them do quarantines with this — of that nature. There’s very limited travel between the US and Russia, obviously,” Rubio said.

“But like anything else, something like that gets out, it could quickly spread. 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 added.

Meanwhile, the US State Department has warned Americans currently in Russia that the US government has “limited ability to help” them amid the ongoing health concerns.

In a travel advisory, the department said, “We continue to track the situation closely. The US government has limited ability to help US citizens in Russia, especially outside of Moscow. US government personnel may face additional restrictions for personal and official travel to specific regions due to health and security concerns.”

Also Read: Russia investigates suspected plague death as health officials step up monitoring

The State Department said its Level 4 travel advisory — “Do Not Travel” — for Russia remains in place and urged US citizens currently in the country to leave immediately.

“US citizens planning travel to Russia are again strongly advised not to travel to Russia due to risk of wrongful detention and security concerns,” the statement said.

The death of a laboratory worker in Russia’s Siberia region has raised concerns over a possible plague case, with the World Health Organization (WHO) saying on Tuesday that it was closely monitoring the situation.

“A woman who worked at the laboratory in Irkutsk oblast has died, and the authorities are looking into whether pneumonic plague caused her death,” WHO spokesperson Christian Lindmeier told reporters in Geneva.

He stressed that she worked at “an institute that studies dangerous pathogens, including plague, in a part of Siberia where plague occurs naturally in wild animals.”

Highly contagious
Plague is caused by the bacterium Yersinia pestis, which is usually found in small mammals and their fleas.

Pneumonic plague occurs when the bacteria infect the lungs. The WHO says this form of plague is particularly contagious and “can trigger severe