The World Health Organization (WHO) stated on the 7th that after a 28-year-old laboratory worker in Siberia, Russia, died last week suspected of having plague, Russian authorities have not yet provided the WHO with a "complete picture" of the incident, making a comprehensive risk assessment impossible.

On the same day, Russia's health regulatory agency said there is no risk of an outbreak occurring locally.

According to Xinhua News Agency, the Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing published a notice on its official website on the 6th stating that a sick employee at the Irkutsk Research Institute of Plague Control of Siberia and the Far East was diagnosed with "pneumonia of unknown origin."

After the incident, local authorities immediately took comprehensive epidemic prevention measures, and the epidemic prevention situation in Irkutsk Oblast and related cities is currently stable.

The incident has drawn international attention, and U.S. President Donald Trump has also expressed concern.

On the 7th, when asked whether the Russian worker died from a biological weapon, Trump told reporters: "We'll know very soon, but we don't think so." He also said Russian officials have assured the United States that the situation is under control.

First Case's Exact Cause of Death Unknown, Second Case Unconfirmed

Russian public health authorities said earlier this week that a laboratory worker at a research institute specializing in plague research in the Irkutsk region died after being diagnosed with pneumonia of "unknown etiology."

On the 7th, Russia released an updated notice stating that the situation is currently "stable" and that follow-up testing of thousands of people in the region found no plague infections.

A Russian media outlet previously reported that the researcher "allegedly broke a test tube containing the pathogen of pneumonic plague on September 25," quickly developed symptoms, was sent to hospital, and ultimately died on October 2.

However, this claim has not been officially confirmed, and the exact cause of death remains unknown.

Maria Van Kerkhove, head of the WHO's Epidemic and Pandemic Management department, said on the 7th that the WHO does not know what the "causative agent" was that led to the woman's death.

"We have raised these questions with our colleagues in the Russian Federation. To be fair, they have responded. We have raised more questions."

According to The Guardian, the Russian researcher was named Darya Shipilova, who died two days after developing cold-like symptoms.

Russia denied that her death was related to the plague institute.

Shipilova's 64-year-old mother Svetlana, in an interview with local media, expressed doubt about the claim that her daughter was infected by breaking a test tube.

She said: "I know the truth. I have been dealing with foolish friends who believe this claim. The test tube simply cannot be broken, even if you throw it against a wall."

Shipilova died at a hospital in the city of Shelekhov, and the local mayor said the hospital has been placed under quarantine.

Senior Russian health officials have traveled to the area.

According to the Russian medical academic journal Baikal Medical Journal, the Irkutsk health department has taken large-scale measures to prevent the potential epidemic from spreading further.

Some Western media outlets, citing unnamed "Russian media," reported that a second person died in Siberia and claimed the person died of plague.

The WHO provided Reuters with a link to a report about the potential second case, which came from the Russian media outlet StarHit.ru, a media organization primarily focused on celebrity gossip content.

WHO Director-General Tedros said: "In fact, we do not have any authority to judge whether these media reports are credible."

Russia has not yet officially responded to reports about the second death.

Russia has notified the WHO that 200 contacts have been placed under quarantine.

When asked by media about the WHO's request for Russia to respond to reports about a second person being ill, Kremlin spokesman Peskov urged caution in treating media reports and not using them directly as a basis for judging the actual situation.

He said: "The vast majority of media reports are disinformation," and suggested basing judgments on information provided by Russia's health regulatory agency.

The Pathogen That Once Caused the "Black Death" Is Now Treatable

Pneumonia is a lung infection that can be caused by multiple factors, including plague, other bacterial infections, and viral respiratory diseases such as influenza and COVID-19.

Pneumonic plague and bubonic plague are caused by the same bacterium.

The former spreads through respiratory droplets, while the latter spreads through the bites of fleas that jump onto infected rodents.

Bubonic plague causes pus-filled skin ulcers.

According to the Associated Press, the pathogen known as Yersinia pestis caused the "Black Death" in the 14th century.

This was one of the single deadliest events in recorded human history, sweeping through Europe, the Middle East, and North Africa, killing as much as 30% to 50% of the local population.

Plague has never been completely eradicated, but it can now be treated with antibiotics.

The WHO explains that symptoms of pneumonic plague include shortness of breath and coughing up blood, and symptoms can appear within as little as 24 hours after exposure to the pathogen.

Without treatment, the disease can be fatal.

"Pneumonic plague can spread through person-to-person contact, which is why people are worried about it," Simon Clarke, Associate Professor of Cellular Microbiology at the University of Reading in the UK, told the BBC.

"But of course, when people think of infectious disease outbreaks, the first things that come to mind are... lockdowns and COVID-19, but that simply will not happen here."

U.S. Sends Diplomatic Note to Russia Requesting Information on the Deceased

According to The Washington Post, regarding Russia's suspected plague case, Trump told media on October 7 local time that Russia has not disclosed much information about the situation, but "they did say they have fully controlled the situation."

Trump also said a call with Russian President Putin had been arranged.

"They are sharing some information with us. We hope they will share more information with our people."

The Trump administration this week sent a formal diplomatic note to Russia requesting more information about the worker's death.

Erica Schwartz, Director of the U.S. Centers for Disease Control and Prevention (CDC), said on the 7th at an event: "(The suspected outbreak) poses a very low threat to the United States."

She said about 200 flights arrive in the United States from Siberia each year, and U.S. federal agencies are currently monitoring incoming travelers from the region.

Due to sanctions and the suspension of flight services after the Russia-Ukraine conflict in 2022, there are currently no direct flights between Russia and the United States.

However, travelers can still legally transfer through aviation hubs such as Istanbul to reach the United States.

Global Cooperation in Public Health Lacks Enforcement Power

The International Health Regulations are global health cooperation rules established by the WHO, requiring member states to report to the WHO when outbreaks with potential international impact are detected.

In theory, these rules are legally binding, but the WHO has no power to compel countries to take action.

Last year, the WHO pushed for the adoption of a "Pandemic Agreement," but due to disagreements over the extent to which poorer countries should share pathogens and the extent to which wealthier countries should share diagnostic tools, vaccines, and treatments, the agreement has not yet fully entered into force.

Tedros said the WHO has asked Russia to provide more information, including laboratory test results on the deceased, the health status of contacts, and what prompted Russia to take those public health measures.

He also said the WHO is investigating reports that another employee at the institute was infected with pneumonia.