Risk assessment for the EU/EEA of the mpox epidemic caused by monkeypox virus clade I in affected African countries : rapid risk assessment

The monkeypox virus (MPXV) clade I epidemic that has been affecting the Democratic Republic of the Congo (DRC) since November 2023 has recently spread to several other African countries including Burundi, Rwanda, Uganda and Kenya. The size of these outbreaks could be larger than reported due to under-ascertainment and under-reporting. On 15 August 2024, one case of MPXV clade Ib was reported in the EU/EEA and more imported MPXV clade I cases will likely occur. It is therefore important for European countries to be prepared to handle such imported cases and prevent secondary transmission. In countries reporting clade I cases, human-to-human transmission through close physical contact and through both sexual and non-sexual transmission has been documented. Although all age groups are represented among cases infected with MPXV clade I, preliminary data show that infections by clade Ib virus concern mostly the adult population, whereas infections by clade Ia concern mostly children. To date, there are still significant uncertainties about the main transmission routes, transmissibility, severity, and natural disease history, and whether these differ between the two circulating subclades of clade I MPXV. Mpox symptoms usually appear 6-13 days (up to 21 days) after infection. The clinical manifestation of the disease includes general febrile symptoms, a distinct rash (papules) on the skin and sores on the mucosa, back pain and muscle aches. The rash may spread quickly throughout the body within three days of experiencing the initial symptoms. Most people experience mild to moderate symptoms that usually last two to four weeks, followed by a full recovery.