Siberia lab worker dies of suspected plague; 200 under observation

A 28-year-old Russian lab worker has died of suspected pneumonic plague in Siberia, prompting nearly 200 people to enter medical observation. Russian authorities have not confirmed the cause of death, citing "pneumonia of unknown etiology." The researcher worked at an anti-plague institute in Irkutsk, and health officials placed contacts under precautionary observation. A local mayor said the inpatient facility was closed for quarantine. The pneumonic plague is highly contagious and can cause severe epidemics, according to the World Health Organization. The U.S. State Department is monitoring the situation, urging Russia to share accurate information quickly. Experts say person-to-person spread is difficult, and a larger outbreak is unlikely. From 2019 to 2025, 10 countries reported over 3,800 suspected plague cases to the WHO, with 423 deaths.