Recent spread of monkeypox across Africa

May 23, 2022

Since May 13, 2022, cases of monkeypox have been reported to WHO from 12 Member States that are not endemic for monkeypox virus, across three WHO regions.

Epidemiological investigations are ongoing, however, reported cases thus far have no established travel links to endemic areas. Based on currently available information, cases have mainly but not exclusively been identified amongst men who have sex with men (MSM) seeking care in primary care and sexual health clinics.

The objective of this Disease Outbreak News is to raise awareness, inform readiness and response efforts, and provide technical guidance for immediate recommended actions.

The situation is evolving and WHO expects there will be more cases of monkeypox identified as surveillance expands in non-endemic countries. Immediate actions focus on informing those who may be most at risk for monkeypox infection with accurate information, in order to stop further spread. Current available evidence suggests that those who are most at risk are those who have had close physical contact with someone with monkeypox, while they are symptomatic. WHO is also working to provide guidance to protect frontline healthcare providers and other health workers who may be at risk such as cleaners. WHO will be providing more technical recommendations in the coming days.

To date, all cases whose samples were confirmed by PCR have been identified as being infected with the West African clade. Genome sequence from a swab sample from a confirmed case in Portugal, indicated a close match of the monkeypox virus causing the current outbreak, to exported cases from Nigeria to the United Kingdom, Israel and Singapore in 2018 and 2019.

Public health response

Further public health investigations are ongoing in non-endemic countries that have identified cases, including extensive case finding and contact tracing, laboratory investigation, clinical management and isolation provided with supportive care.

Genomic sequencing, where available, have been undertaken to determine the monkeypox virus clade(s) in this outbreak

Vaccination for monkeypox, where available, is being deployed to manage close contacts, such as health workers. WHO is convening experts to discuss recommendations on vaccination.

WHO has developed surveillance case definitions for the current monkeypox outbreak in non-endemic countries.

Suspected case:

  • A person of any age presenting in a monkeypox non-endemic country with an unexplained acute rash

AND                                        

One or more of the following signs or symptoms since March 15, 2022:

  • Headache
  • Acute onset of fever (>38.5oC),
  • Lymphadenopathy (swollen lymph nodes)
  • Myalgia (muscle and body aches)
  • Back pain
  • Asthenia (profound weakness)

AND

for which the following common causes of acute rash do not explain the clinical picture: varicella zoster, herpes zoster, measles, Zika, dengue, chikungunya, herpes simplex, bacterial skin infections, disseminated gonococcus infection, primary or secondary syphilis, chancroid, lymphogranuloma venereum, granuloma inguinale, molluscum contagiosum, allergic reaction (e.g., to plants); and any other locally relevant common causes of papular or vesicular rash.

Monkeypox endemic countries are: Benin, Cameroon, the Central African Republic, the Democratic Republic of the Congo, Gabon, Ghana (identified in animals only), Côte d’Ivoire, Liberia, Nigeria, the Republic of the Congo, and Sierra Leone. Benin and South Sudan have documented importations in the past. Countries currently reporting cases of the West African clade are Cameroon and Nigeria. With this case definition, all countries except these four should report new cases of monkeypox as part of the current multi-country outbreak.

WHO release