Epidemiological update – Week 35/2024: Mpox due to monkeypox virus clade I

Since the beginning of mpox monitoring in 2022 and until 31 July 2024, 102 977 confirmed cases of mpox due to MPXV clade I and clade II, including 219 deaths, have been reported by 121 countries globally, according to WHO (2022-24 Mpox (Monkeypox) Outbreak: Global Trends (shinyapps.io)). All cases of MPXV clade I have been reported from the African continent apart from one reported by Sweden and one by Thailand.

Epidemiological situation in Africa

In 2024, over 20 000 mpox cases due to MPXV clade I and clade II have been reported from 13 African Union Member States, including over 3 000 confirmed cases and over 500 deaths (CFR 2.9%) according to the Africa CDC Epidemic Intelligence Report issued on 25 August 2024 and the WHO AFRO weekly report of 23 August. These countries are: Burundi (702 cases), Cameroon (35 cases; two deaths), Central African Republic (CAR) (45), Republic of the Congo (Congo) (162 cases; 0 death), Cote d’Ivoire (28 cases; one death), Democratic Republic of Congo (DRC) (19 667 cases; 575 deaths), Gabon (one case), Liberia (six cases), Kenya (two cases), Nigeria (39 cases), Rwanda (four cases), South Africa (24 cases; three deaths) and Uganda (four cases).

In 2023, 14 838 people with confirmed and suspected MPXV infection were reported from Cameroon, CAR, Congo, DRC, Ghana, Liberia, and Nigeria. 

The Democratic Republic of Congo has reported the most people with mpox in the 13 African countries reporting cases, with a cumulative number (19 667) of clade Ia and clade Ib infections (2 961 confirmed and 16 706 suspected) including 575 deaths (Africa CDC Epidemic Intelligence Report issued on 25 August 2024). In DRC, 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.

Burundi has reported most people with mpox due to clade Ib outside DRC and community transmission is presumed. According to the Africa CDC report of 25 August 2024, 190 confirmed and 512 suspected cases had been reported in total from Burundi in 2024 from 26 out of 49 health districts.

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 increase in people with mpox and declared the current MPXV clade I outbreak 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.

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 provided the following additional recommendations for Competent Authorities for Substances of Human Origin (SoHO) and SoHO professionals:

• MPXV has been detected in blood, urine, tissue abscesses and bodily fluids and could potentially be transmitted through SoHO. However, to date, there has been no reported transmission of MPXV through SoHO and the likelihood of this is unknown [4-7]. 
• Prospective donors returning from countries where clade I MPXV has been detected and who are not deferred due to other risks should be carefully interviewed regarding their contact with people suspected or confirmed with mpox or their contact with infected animals. In the event of deceased donors, data on these risk factors from the deceased person’s medical history should be collected. 
• Based on the incubation period, it is recommended to defer asymptomatic donors who have been in contact with people with mpox clade I or II (confirmed or suspected) from SoHO donation, for a minimum of 21 days from the last day of exposure. 
• People with confirmed or suspected MPXV infection should be deferred from donation for at least 14 days after resolution of all symptoms. 

ECDC contributors (in alphabetical order)

Xanthi Andrianou, Jenny Mohseni Skoglund 

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). Communicable disease threats report, 24-30 August 2024, week 35. Stockholm: ECDC; 2024. Available at: https://www.ecdc.europa.eu/en/publications-data/communicable-disease-threats-report-24-30-august-2024-week-35
4. Lapa D, Carletti F, Mazzotta V, Matusali G, Pinnetti C, Meschi S, et al. Monkeypox virus isolation from a semen sample collected in the early phase of infection in a patient with prolonged seminal viral shedding. Lancet Infect Dis. 2022 Sep;22(9):1267-9. 
5. Mbala PK, Huggins JW, Riu-Rovira T, Ahuka SM, Mulembakani P, Rimoin AW, et al. Maternal and Fetal Outcomes Among Pregnant Women With Human Monkeypox Infection in the Democratic Republic of Congo. J Infect Dis. 2017 Oct 17;216(7):824-8. 
6. Ritter JM, Martines RB, Bhatnagar J, Rao AK, Villalba JA, Silva-Flannery L, et al. Pathology and Monkeypox virus Localization in Tissues From Immunocompromised Patients With Severe or Fatal Mpox. J Infect Dis. 2024 Mar 26;229(Supplement_2):S219-s28. 
7. Suñer C, Ubals M, Tarín-Vicente EJ, Mendoza A, Alemany A, Hernández-Rodríguez Á, et al. Viral dynamics in patients with monkeypox infection: a prospective cohort study in Spain. Lancet Infect Dis. 2023 Apr;23(4):445-53.