Evolving Epidemiology of Mpox in Africa in 2024.

Abstract

Background: For decades after the identification of mpox in humans in the Democratic Republic of Congo (DRC) in 1970, the disease was largely confined to the rural areas of Central and West Africa and thus did not garner broad attention. On August 13, 2024, mpox was declared a Public Health Emergency of Continental Security (PHECS) by the Africa Centers for Disease Control and Prevention (Africa CDC), a notice that was followed the next day by a declaration of a Public Health Emergency of International Concern (PHEIC) by the World Health Organization.

Methods: In this study we analyzed all mpox cases and deaths, based on clinical or laboratory diagnosis, that were reported to the Africa CDC from January 1, 2022, to October 30, 2024, to identify temporal variations, geographic distributions, and epidemiologic trends.

Results: From January 1, 2022, to August 18, 2024, a total of 45,652 mpox cases were clinically diagnosed and laboratory-confirmed in 12 African countries. These cases resulted in 1492 deaths (case fatality rate, 3.3%). From 2022 to 2024, weekly laboratory-confirmed mpox cases increased by a factor of 2.8 (from 176 to 489 cases), whereas all weekly reported cases (including those with a clinical diagnosis) increased by a factor of 4.3 (from 669 to 2900 cases). The DRC, which had reported approximately 88% of mpox cases in Africa in 2024, had 19,513 cases before the emergency declaration, with a case fatality rate of 3.1% - a weekly average of 591 cases as compared with 281 in 2023. In 2024, six African countries reported their first imported mpox infections, with Burundi also reporting local transmission.

Conclusions: The high mpox disease burden in Africa, especially in the DRC - with a rising number of cases, high case fatality rate, and high degree of spread to other previously mpox-free African countries - is cause for increased international concern. Case detection, contact tracing, public health measures, and affordable vaccines are needed to implement interventions in the DRC to reduce the risk of global spread of the virus.