Explainer
What is plague? The three forms, the treatment and the Russian case explained
Plague is a treatable bacterial infection of rodents and fleas that kills when treatment starts late; pneumonic plague is the one form that spreads person to person. What WHO, CDC and ECDC say about the disease, and what is and is not known about the suspected case at a plague laboratory in Irkutsk, Russia, as of 6 October 2026.