Mpox: 18 new cases

Public Health France (SPF) published (March 30) a point update on March 23, 2023 on cases of Mpox (Monkeypox or monkeypox) following the reporting and investigation of clustered cases in the Centre-Val de Loire region. As of March 23, 2023, 5,000 cases of infection with the Mpox virus have been recorded in France, i.e. 18 additional cases since the assessment of January 24. Among these 5,000 cases, 4,144 (83%) were biologically confirmed and 856 (17%) are probable or possible cases, not biologically confirmed. The Île-de-France region concentrates the largest number of cases (3,120, or 63%), followed by Auvergne-Rhône-Alpes (356 cases), Provence-Alpes-Côte d’Azur (334 cases ), and Occitania (330 cases); 27 cases reside abroad. The 18 new cases declared since the last report all concern men and 17 of them were diagnosed in the Centre-Val de Loire region. The vast majority of adult cases reported to date are male and 2.9% are female over the age of 15 (143 cases, including 113 biologically confirmed cases and 30 unconfirmed cases). No female cases have been diagnosed since the assessment of January 24, 2023. The median age of adult cases is 36 years; 25% of cases are under 29 years old and 25% are between 43 and 81 years old. Twenty-four children under the age of 15 (0.5% of total cases) have been reported since May 2022 (12 biologically confirmed cases and 12 unconfirmed cases). No pediatric case has been diagnosed since the report of January 24, 2023. Non-biologically confirmed cases have a profile comparable to confirmed cases: 3.7% of adults are female (versus 2.8% of confirmed adult cases) , the median age of adults is 36 years as in confirmed cases and the majority resides in Île-de-France (72% versus 60% of confirmed cases). Of all the cases for which information is available, 101 (2.0%) were hospitalized for treatment of their Mpox virus infection; this proportion is stable over time. No deaths have been reported to date. With regard to the 17 cases grouped in the Centre-Val de Loire region, the investigation carried out by SpF showed that all these cases concerned men who have sex with men (MSM), several of whom reported having had several partners without always being able to identify them. No parties or events common to the cases were identified. Six of the 17 cases received no vaccination against Mpox, one reported having an incomplete vaccination regimen (vaccination in childhood with a 1st generation smallpox vaccine) and ten reported a complete vaccination regimen: five with one 1st generation smallpox vaccine in childhood + one dose of 3rd generation vaccine in 2022, and five with two doses of 3rd generation vaccine in 2022. 3rd generation vaccines against Mpox infection. There are no data on long-term protection after a full vaccination course, nor in population subgroups,” says SPF. And the health agency concludes: “Pending robust data on the real-life effectiveness of vaccines against Mpox, this cluster calls for vigilance. Mpox infections can occur in people who have received a full course of vaccination, and it is important to consider this diagnosis in case of rash or mucous membrane, including in people who are correctly vaccinated”.