A 28-year-old female laboratory worker at a Russian institute researching plague has died in Siberia, Russia, after a suspected exposure to the Yersinia pestis bacteria. Daria Shipilova, a lab assistant at the Irkutsk Anti-Plague Institute of Siberia and the Far East, died last week after becoming very ill. Reports suggest she was exposed to live bacteria when she reportedly accidentally broke a test tube containing the pathogen while collecting samples. She was placed on a ventilator but died on Thursday.
Nearly 200 people under observation
The incident is said to have prompted authorities to place nearly 200 people under observation. Russia’s national public health agency, Rospotrebnadzor, said she had contracted “pneumonia of unknown aetiology [cause].”
There are multiple types of plague, all caused by the Yersinia pestis bacteria. These include bubonic, pneumonic, and septicaemic plague. Bubonic plague is the most common form and is caused by the bite of an infected flea. Pneumonic plague, or lung-based plague, is the most virulent form, while septicaemic plague occurs when the bacteria multiplies rapidly in the bloodstream and can develop from any other form of plague.
Expert warns of rapid progression
Professor Brendan Wren of the London School of Hygiene & Tropical Medicine (LSHTM) said: "Plague is a serious infectious disease caused by the bacterium Yersinia pestis. Historically, the disease was transmitted from infected fleas to humans, although human-to-human spread can occur through respiratory droplets in cases of pneumonic plague. It can cause a rapidly progressing septicaemia that may become life-threatening within 48 hours if left untreated."
He added: "Reports from Russia about this case suggest that the infection resulted from an accidental inoculation following a broken test tube, highlighting the importance of strict biosafety procedures when handling dangerous pathogens."
Professor Wren also said: "While this incident has attracted global attention, laboratory-acquired infections with Yersinia pestis are rare because human-to-human transmission of plague is relatively uncommon compared with respiratory viruses such as SARS-CoV-2 or COVID-19. In this case, I would not describe the accidental laboratory-based transmission to a single individual as an outbreak, and it seems unlikely that it will lead to a wider epidemic."
Treatment and symptoms
Although pneumonic plague is the most severe form of the disease, as it can spread via the respiratory route, it remains treatable with antibiotics when diagnosed promptly. Globally, around 2,000 cases are reported each year, mostly in areas where the disease remains endemic, including regions of the western United States, where public health authorities have extensive experience in managing suspected exposures.
The World Health Organization says symptoms of pneumonic plague can develop rapidly, sometimes within 24 hours of infection. It states: "Pneumonic plague, or lung-based plague, is the most virulent form of plague. Incubation can be as short as 24 hours. Any person with pneumonic plague may transmit the disease via respiratory particles to other humans."
It adds: "Untreated pneumonic plague, if not diagnosed and treated early, can be fatal. However, recovery rates are high if detected and treated in time (within 24 hours of onset of symptoms)." Symptoms of the pneumonic form appear quickly after infection and include severe respiratory symptoms such as shortness of breath and coughing, often with blood-tainted sputum.
