Smallpox, one of the biggest killers in history, is caused by a virus called variola. Variola causes a distinctive rash and is often lethal. The name variola comes from the Latin word for “spotted” ...

Monkeypox is a disease caused by the monkeypox virus, a pathogen closely related to variola virus, which causes smallpox. Monkeypox and smallpox infections trigger similar symptoms, but monkeypox ...