Clade I Mpox Outbreak Originating in Central Africa

What to know

  • Since January 1, 2024, the Democratic Republic of the Congo and several neighboring countries in Central and Eastern Africa have confirmed through laboratory testing more than 21,000 mpox cases and more than 65 deaths.
  • There have also been travel-associated cases in other parts of Africa, Europe, Asia, and North America.
  • The risk of clade I mpox to the public in the U.S. remains low.
CDC is working with international partners to respond to clade I mpox

Situation summary

In the United States

CDC mpox prevention recommendations

Learn more about which activities may put you at increased risk of exposure when you travel to a country where clade I MPXV is spreading.

CDC has updated prevention and vaccination recommendations for people traveling to countries with clade I outbreaks. As of February 12, 2025, these countries include Burundi, Central African Republic, Democratic Republic of the Congo, Kenya, Republic of the Congo, Rwanda, Uganda, and Zambia.

In Central and Eastern Africa

  • There are several outbreaks happening at the same time in the Democratic Republic of the Congo (DRC), with cases reported throughout the country, in the capital city of Kinshasa, and in some other large cities.
  • Clade Ia mpox cases are impacting the western part of DRC. Although most cases have not been laboratory-confirmed, available data indicate that clade Ia mpox is spreading through multiple modes of transmission, including contact with infected dead or live wild animals, household contact often involving crowded households, or sexual contact.
  • Clade Ib mpox cases were recently identified in eastern DRC. Available data indicate that these cases are mostly spreading through intimate or sexual contact between adults at first, then spread likely occurs within households, including to children.
  • The bordering countries of Republic of the Congo (ROC) and Central African Republic (CAR), where clade I mpox occurs regularly, are experiencing clade Ia mpox outbreaks; some of the cases appear to be linked to spread from DRC.
  • In summer and fall 2024, the disease spread to neighboring countries to the east of DRC that are not known to be endemic for the virus that causes mpox, and sustained local spread occurred. These include Burundi, Rwanda, and Uganda. In winter 2024, Kenya and Zambia began experiencing local human-to-human transmission.
  • Person-to-person transmission has occurred during this outbreak, including through sexual contact, household contact, and within healthcare settings, when personal protective equipment was not available.
Map of Central and Eastern Africa showing countries with endemic and non-endemic mpox
Mpox cases are occurring in several countries in Central and Eastern Africa

CDC has been supporting DRC mpox research and response for more than 20 years. CDC and other U.S. government agencies are on the ground in DRC helping partners in the country with disease surveillance, laboratory capacity including testing materials, strengthening workforce capacity, case investigation, case management, infection prevention and control, border health, and risk communication and community engagement. DRC has approved the use of vaccines in-country, so CDC is working with other U.S. government agencies and partners on a strategy for vaccination in DRC.

CDC is working with Ministries of Health and in-country partners across the region on disease surveillance, laboratory capacity including testing materials, strengthening workforce capacity, case investigation, case management, infection prevention and control, border health, and risk communication and community engagement.

More about US and global mpox cases and outbreaks

Learn more about outbreaks of clade I and clade II mpox on the Mpox Current Situation page.

two women stand by a table covered in boxes, which contain laboratory testing supplies for mpox
CDC staff in Burundi with donated laboratory supplies to be used for mpox testing

Cases reported after travel to areas with clade I outbreaks

Country

Date

Kenya

July 2024

Sweden

August 2024: First clade I mpox case to be reported outside of the African continent.

Thailand

August 2024

India

September 2024

Germany

October 2024 and December 2024 (three additional cases from the same household were reported in December 2024)

United Kingdom

October 2024 (three additional cases from the same household were reported in November 2024); December 2024, February 2025

Zambia

October 2024

Zimbabwe

November 2024

United States

November 2024; January 2025; February 2025 (2 separate cases)

Canada

November 2024

Belgium

December 2024

Oman

December 2024

Pakistan

December 2024

France

January 2025

China

January 2025

Ireland

February 2025

South Sudan

February 2025

A single person or household with mpox is not cause for widespread concern, since public health authorities can quickly identify, isolate, and treat the person or family, and the risk of spread to other people and households can be minimized. Rapid response measures, such as contact tracing and vaccination, can effectively stop disease spread in these situations.

Notes: Case data reported in humans to WHO since January 1, 2024, are provided for situational awareness and subject to change. Confirmed cases include those laboratory-confirmed as monkeypox virus and may include cases only confirmed as orthopoxvirus. For more information and additional limitations, see WHO-reported data at 2022-24 Mpox (Monkeypox) Outbreak: Global Trends (shinyapps.io).

Source: 2022-24 Mpox Outbreak: Global Trends. Geneva: World Health Organization, 2024. Available online: https://worldhealthorg.shinyapps.io/mpx_global/ (last cited: August 27, 2024)

Resources

Publications