The World Health Organization (WHO) has asked the Russian government for more information about the death of an employee at a Siberian plague research unit, including details about the laboratory tests conducted on her, the WHO Director-General told a media briefing on Thursday.

The WHO has also asked Russia for more details about the public health measures it has imposed, the health status of the woman’s contacts, and whether a second employee has been infected with “pneumonia of undetermined cause”, said Dr Tedros Adhanom Ghebreyesus.

This follows reports on Monday of the death of a 27-year-old female employee at the Irkutsk Anti-plague Research Institute of Siberia and the Far East – possibly of pneumonic plague.

The employee was hospitalised at Shelekhov Hospital on 29 September with symptoms of pneumonia, placed on a ventilator and died a few days later, according to media reports.

Tedros said that the WHO had sent queries to Russia on Saturday, and received a report on Wednesday that “no case of plague had recently been reported in the Irkutsk Oblast” where the research unit is, and that they had “placed about 200 [of the woman’s] contacts in quarantine”.

WHO has also offered Russia technical support related to “plague and lab biosafety and biosecurity”, Tedros said, adding that “we don’t yet have the full picture of this event, and we are not able to conduct a full risk assessment”.

Broken test tube?

Some media reports say the employee died after breaking a test tube in the laboratory, but Dr Maria van Kerkhove, WHO director of Epidemic and Pandemic Management, said that employees working in such laboratories would wear personal protective equipment (PPE) and be vaccinated against various diseases.

“We are following up on what type of PPE would be used, and under which conditions? What were they doing with these pathogens?” said Van Kerkhove.

“If there was a lab incident in this lab, there are procedures that must be followed in terms of the assessment that they do in the lab. There would be post-exposure prophylaxis, for example, for this individual. They would probably run tests, so there’s more to come as it relates to what actually happened,” she explained.

“What we have been told is that [Russia] has no case of plague registered in this area, and that no high threat pathogens were detected. So clearly, we would like more information to understand which laboratory tests were conducted, which pathogens were evaluated, and if this individual didn’t die from plague, then then how did she die?” Van Kerkhove added.

Plague is a severe, life-threatening infection caused by the bacterium Yersinia pestis and there are two types: bubonic and pneumonic. 

However, Van Kerkhove said there are thousands of cases of suspected plague every year around the world: “Between 2019 to 2025, 10 countries reported almost 4,000 suspected human plague cases and 423 deaths.”  

Central Asia is the hot spot, and people are infected by bacteria carried by small rodents.

“Sometimes there are small, sporadic outbreaks. Plague is caused by a bacteria. There are antibiotics that can treat this. So if anyone does have an infection with plague, it can be treated.”

International Health Regulations requirements

In terms of the International Health Regulations (IHR), WHO member states are legally obliged to assess public health risks and notify the WHO of any event that may constitute a public health emergency of international concern (PHEIC) within 24 hours of assessment.

Although the WHO submitted its queries to Russia in terms of the IHR on Saturday, it took the government more than three days to respond.

Dr Silvio Ciobanu from WHO’s European region and an IHR expert said countries have to answer four key questions in terms of the IHR: “How severe is the public health impact? Is it unusual and expected? Does it pose a risk of international spread? And does it pose a risk of trade or travel restrictions?”

Ciobanu added that the IHR are “very explicit that a response is expected within 24 hours, and then after that, state parties may require a little bit of extra time to collect all the additional information”.