The enduring legacy of a forgotten killer and its modern-day threat

As mpox cases spread across Europe, experts suggest this rise may be linked to declining immunity against its far more lethal relative, smallpox. In 1970, doctors in the Democratic Republic of Congo encountered a case that would reignite fears thought to have been eradicated. A nine-year-old boy in a remote village developed a severe rash. The skin lesions covering his body bore a striking resemblance to smallpox, an ancient disease that had devastated empires, wiped out civilizations, and claimed approximately 300 million lives in the 20th century alone. Smallpox was believed to be eradicated in the DRC, but scientists feared that this case, found in an unvaccinated child, might have been overlooked. Tests later confirmed that the child was suffering from monkeypox (now called mpox), a close relative of smallpox, belonging to the orthopoxvirus family (which also includes cowpox and raccoonpox). Although mpox was first identified in 1958 during outbreaks in research...