What is mpox? A microbiologist explains what’s known about this smallpox cousin

Abstract

On Aug. 14, 2024, the World Health Organization declared mpox a public health emergency of international concern. There have been over 15,600 cases and over 530 deaths reported in the Democratic Republic of the Congo and neighboring countries in Africa. The disease had previously caused a global outbreak from 2022 to 2023.

Mpox – previously called monkeypox – isn’t a new disease. The first confirmed human case was in 1970, when the virus was isolated from a child suspected of having smallpox in the Democratic Republic of Congo (DRC). Though usually mild, mpox can still potentially cause severe illness. Health officials are concerned that more cases will arise with increased travel.

I’m a researcher who has worked in public health and medical laboratories for over three decades, especially in the realm of diseases with animal origins. What exactly is happening in the current outbreak, and what does history tell us about mpox?