What is the plague in Russia and should the PH be worried?

MANILA (UPDATED) — The reported death of a laboratory researcher in Russia following possible exposure to live bacteria has renewed attention on one of the world’s oldest and deadliest infectious diseases: The plague.

The researcher was working at an anti-plague research institute in Siberia’s Irkutsk region when she came into contact with a broken test tube containing live bacteria, according to media reports.

She was later hospitalized and reportedly died of pneumonic plague, which sparked alarm last week and raised questions about pneumonic plague, the rare but most severe form of the disease.

But should Filipinos be worried?

Health authorities say there is no reason for widespread alarm based solely on the reported incident in Russia.

The Philippines has not been known to have endemic human plague transmission, which means there is no established ongoing cycle of human plague transmission in the country.

The primary concern would be an imported infection, such as a person becoming infected in an area where the plague is circulating and subsequently entering the Philippines. 

For pneumonic plague, authorities would also need to consider the possibility of exposure to someone who is infected and contagious.

Health Secretary Edwin Mercado told ABS-CBN News that the Bureau of Quarantine is already monitoring the situation and that they are “working closely” with the World Health Organization.

WHO said Tuesday that it deemed the public health risk in Russia to be low following the laboratory technician’s death.

The incident has yet to be elevated as a “matter of concern,” said Mercado, who noted that the agency is nevertheless preparing “internally.”

He noted the “swift” action of Russia, which already isolated those who were potentially exposed to the researcher who had supposedly died of pneumonic plague.

WHO spokesman Christian Lindmeier said the lab technician, identified as 28-year-old Darya Shipilova, worked at an institute that studies dangerous pathogens in a part of Siberia where plague occurs naturally in wild animals.

He told a press briefing in Geneva in Switzerland that the authorities are looking into whether pneumonic plague caused her death.

Lindmeier said Russian authorities had identified the people she was in contact with and had been monitoring them.

“According to the test results, no pathogens of dangerous infectious diseases were detected among any of the contacts,” he said.

“WHO is following the situation closely, working with headquarters to keep other countries informed,” and stands ready to support the Russian authorities if they ask. 

The response highlights an important principle in infectious disease control that preparation does not necessarily mean there is an imminent threat. 

Learning from the experience during the COVID-19 pandemic, health authorities can increase surveillance, coordinate with international organizations and prepare quarantine measures even while the overall risk to the public remains low.

At present, the reported incident in Siberia does not indicate an outbreak or an imminent threat to the Philippines.

The more important issue for Philippine health authorities is surveillance. 

This means monitoring developments, identifying any person who may have been exposed in an affected area, detecting symptoms early, and preventing further transmission should an imported case be identified.

Plague is an infectious disease caused by the bacteria Yersinia pestis. It is primarily a disease of rodents and other small mammals and is usually transmitted to people through the bite of an infected flea.

People can also become infected by handling infected animals.

Unlike the other forms of plague, however, pneumonic plague can spread from person-to-person through respiratory droplets, particularly when an infected person has a cough or other respiratory symptoms.

There are three main forms of plague:

• Bubonic plague: The most common form which infects the lymphatic system and causes painful, swollen lymph nodes called buboes.
• Septicaemic plague: Occurs when the bacteria enter and multiply in the bloodstream, potentially causing severe bleeding, tissue damage and organ failure.
• Pneumonic plague: Infects the lungs and can cause severe pneumonia. It is the most dangerous form because it can progress rapidly and, unlike bubonic plague, can be transmitted directly between people through respiratory droplets.

Infectious diseases specialist Dr. Rontgene Solante said that pneumonic plague “destroys” alveoli, the tiny air sacs in the lungs where oxygen enters the blood and carbon dioxide is removed.

Pneumonic plague produces toxins that could cause “a lot of damage directly to the lungs that’s more severe, more rapid” compared to COVID, he added.

Pneumonic plague can lead to complications such as respiratory failure, pulmonary hemorrhage and acute respiratory distress syndrome, or ARDS.

The disease can progress much faster than many other respiratory infections.

Solante said symptoms can begin within roughly 48 to 72 hours after exposure, although the exact incubation period can vary.

If untreated, severe disease may develop within days.

“In fact, most people will die within seven days, within a week upon exposure. That’s how rapid the progression of pneumonic plague,” he said.

This is why early detection and treatment are critical.

Unlike COVID-19, which is caused by a virus, plague is caused by a bacteria.

This distinction is important because bacterial infections can be treated with antibiotics that are effective against Yersinia pestis, the bacterium responsible for causing plague.

Several antibiotics can be used to treat plague, and treatment is most effective when started as early as possible.

People who have been exposed to a confirmed case may also be given preventive antibiotics, depending on the circumstances.

For pneumonic plague in particular, delaying treatment can be fatal because the infection can rapidly progress to severe pneumonia and respiratory failure.

Yersinia pestis continues to circulate naturally among animal populations, particularly rodents, in parts of Africa, Asia and the Americas.

The presence of the bacteria in animal populations means that human cases can occasionally occur when people come into contact with infected animals or fleas.

WHO data from recent years have recorded suspected and confirmed plague activity in parts of Africa, Asia and the Americas.

Countries that have reported plague cases include Madagascar, the Democratic Republic of the Congo, Mongolia, China and Taiwan.

But human plague cases remain relatively rare.

The disease is also very different from the plague outbreaks of the past.

The plague is best known for the Black Death, a pandemic that swept through Europe, Asia and North Africa in the 14th century and killed tens of millions of people.

But the modern plague is not the same public health threat it was hundreds of years ago.

Today, doctors have a much better understanding of how the disease spreads, laboratories can identify the bacterium, antibiotics are available, and health authorities can isolate patients and monitor people who may have been exposed. —With a report from Agence France-Presse