‘No plague case’ in Siberia, Russia tells WHO as assessments continue

This article is published in association with United Nations.

Health authorities in Russia say there is “no plague case” in Siberia following reports last week that a lab technician had died of pneumonia of an unknown origin in the region, World Health Organization (WHO) officials said on Wednesday.

Russian regulators told WHO on Tuesday that there was no evidence pneumonic plague played a part in her death and that no pathogens had been detected, agency chief Tedros Adhanom Ghebreyesus said. About 200 of her contacts have been placed in quarantine.

Further requests for information have been sent to Russian authorities, he added, noting that the lab is part of an institute in Irkutsk that studies dangerous pathogens, including plague, which occurs naturally in wild animals in the area.

Tweet URL

Post-COVID fears

When reports emerged last week of a possible pneumonic plague outbreak in Irkutsk, WHO immediately began monitoring and carrying out risk assessments.

Maria Van Kerkhove, who heads WHO’s department of epidemic and pandemic threat management, said the health agency has reached out to Russia for details on lab results, tests and further analysis.

She said the request included further information regarding media reports of another suspicious pneumonia death in the region.

Acknowledging that the world has a “heightened attention to risk” because of the 2020 COVID-19 global pandemic that killed more than 20 million people, Dr. Van Kerkhove said “we want to put out fair, factual information and when we don’t have an answer, we say so.”

Meanwhile, WHO has offered support to Russia and expects further answers from Moscow in the coming days, she said, emphasising that the agency will share new information as soon as it becomes available.

Fatal consequences

Cases of the deadly plague infection, which is caused by the Yersinia pestis bacteria usually found in small mammals and their fleas, are reported around the world every year, Dr. Van Kerkhove said.

Nearly 4,000 cases and 423 deaths were reported across 10 countries between 2019 and 2025, according to a WHO report.

Highly contagious pneumonic plague occurs when bacteria infect the lungs and it “can trigger severe epidemics through person-to-person transmission via respiratory particles”, according to WHO. 

If left untreated, the disease can be fatal within 18 to 24 hours of its onset. 

But common antibiotics for enterobacteria can effectively cure the disease if they are delivered early, the UN health agency said.

Fast facts

• Bubonic plague is the most common clinical form of plague and less common but severe forms include septicaemic and pneumonic plague
• The disease is transmitted between animals and humans through the bite of infected fleas, direct contact with infected tissues and inhalation of infected respiratory particles
• Plague has a case-fatality ratio of 30 to 60 per cent for the bubonic type, and it is always fatal for pneumonic and septicaemic strains when left untreated
• Antibiotic treatment is effective against plague bacteria, so early diagnosis and treatment can save lives
• Human plague remains endemic in several countries, with most of nearly 4,000 reported cases between 2019 and 2025 located in the Democratic Republic of the Congo and Madagascar