Epidemiological update – Week 36/2024: Mpox due to monkeypox virus clade I

Since the beginning of mpox monitoring in 2022, and as of 31 July 2024, over 100 000 confirmed cases of mpox due to monkeypox virus (MPXV) clade I and clade II, including over 200 deaths among confirmed cases, have been reported by more than 120 countries globally according to the World Health Organization (WHO) (2022-24 Mpox (Monkeypox) Outbreak: Global Trends). All the cases of mpox due to MPXV clade I have been reported from the African continent, apart from one case reported by Sweden and one by Thailand.

Epidemiological situation in Africa

In 2024, over 20 000 mpox cases, including over 600 deaths (confirmed and suspected), due to MPXV clade I and clade II have been reported from Africa Union Member States, including over 5000 confirmed cases, according to the Africa CDC Epidemic Intelligence Report issued on 31 August 2024 and the WHO AFRO weekly report of 30 August. The reporting countries are Burundi, Cameroon, the Central African Republic, the Republic of the Congo, Côte d’Ivoire, the Democratic Republic of Congo (DRC), Gabon, Liberia, Kenya, Nigeria, Rwanda, South Africa, and Uganda. 

The epidemiological situation remains similar to the previous week. Since the previous update, one new country, Guinea, has reported one mpox case. The clade has not yet been determined (WHO Global update reporting data as of 1 September and media reported on it quoting official authorities).

The two countries reporting the largest numbers of cases in recent weeks remain the DRC and Burundi:

• The DRC continues to report the highest number of mpox cases in Africa, with 1 838 confirmed, 1 095 suspected cases and 35 deaths reported since 23 August, and as of 30 August (Africa CDC report). The cumulative number of cases in 2024 is over 20 000 infections (4 799 confirmed and 17 801 suspected), including 610 deaths (Africa CDC Epidemic Intelligence Report issued on 31 August 2024). According to the WHO Global report on mpox, 27 confirmed mpox deaths have been reported in the DRC overall, 25 in 2024 as of 25 August. MPXV clades Ia and clade Ib are circulating. The majority of cases and deaths reported are among <15-year-olds (66% of cases and 82% of deaths) while males account for 73% of all people with mpox, according to Africa CDC.
• In Burundi, as of 1 September 2024, 328 confirmed cases have been reported according to the WHO (2022-24 Mpox (Monkeypox) Outbreak: Global Trends). According to the WHO AFRO weekly situation report of 30 August, cases were reported from 29 of 49 districts. Over a third of cases (37.5%) were reported among children under 10 years (24% among <5-year-olds) and 24.6% among those aged 20 to 30 years. There is a slight preponderance of males among cases (56%). The test positivity rate is 37.6% (455 tests conducted in total, as of 28 August).

Additional updates:

• As of 2 September, Uganda had reported 10 confirmed mpox cases. Of these, seven were reported outside Kasese, which is the area bordering the DRC where three cases have been reported overall (including the first two cases reported in Uganda). At least seven cases have no history of travel in affected areas and two were reported from Kampala.
• Kenya has reported five mpox cases. The first two cases were males who had been detected at points of entry. The third case, reported on 30 August, is a female with travel history to Uganda. The case was reported in Nairobi. On 31 August, a fourth case was reported from Nakuru country (travel history to Rwanda) and a fifth case linked to the fourth was reported on 6 September. Clade Ib has been detected.
• Liberia reported one mpox case on 2 September 2024 and another one on 7 September 2024, although the clade has not been identified yet. An additional six cases have been reported to date in 2024, the most recent in August but before the declaration of the Public Health Emergency of Continental Security by Africa CDC on 13 August 2024. In total, eight cases have been reported in the country.

On 13 August 2024, Africa CDC declared mpox a Public Health Emergency of Continental Security. On 14 August 2024, WHO convened a meeting of the IHR Emergency Committee to discuss the mpox upsurge and declared the current outbreak of mpox due to MPXV clade I a public health emergency of international concern.

Epidemiological situation in the EU/EEA

On 15 August 2024, Sweden reported the first imported case of mpox due to MPXV clade Ib in EU/EEA countries. As of 5 September, no secondary cases have been detected.

Recommendations

In addition to the recommendations published in the Rapid Risk Assessment for the EU/EEA of the mpox epidemic caused by monkeypox virus clade I in affected African countries [1] on 16 August 2024, ECDC has collected rapid scientific advice for public health authorities in EU/EEA countries on this website (Mpox rapid scientific advice on public health measures), particularly related to the following topics:

• Information for travellers to areas with ongoing MPXV transmission;
• Diagnosis and isolation of cases, and infection prevention and control measures;
• Contact tracing;
• Substances of human origin;
• Vaccination;
• Surveillance.

References

1. European Centre for Disease Prevention and Control (ECDC). Risk assessment for the EU/EEA of the mpox epidemic caused by monkeypox virus clade I in affected African countries. Stockholm: ECDC; 2024. Available at: https://www.ecdc.europa.eu/en/publications-data/risk-assessment-mpox-epidemic-monkeypox-virus-clade-i-africa
2. European Centre for Disease Prevention and Control (ECDC). Epidemiological update: Mpox due to monkeypox virus clade I. Stockholm: ECDC; 2024. Available at: https://www.ecdc.europa.eu/en/news-events/epidemiological-update-mpox-due-monkeypox-virus-clade-i
3. European Centre for Disease Prevention and Control (ECDC). Epidemiological update – Week 35/2024: Mpox due to monkeypox virus clade I. Stockholm: ECDC; 2024. Available at: https://www.ecdc.europa.eu/en/news-events/epidemiological-update-mpox-due-monkeypox-virus-clade-i