Demographic, clinical and microbiological characteristics of the first 30 human monkeypox confirmed cases attended in a tertiary hospital in Madrid (Spain), during the May-June 2022 international outbreak.

The present outbreak of Human Monkeypox (HMPX) that has begun in May 2022 and has spread across all continents in less than two months has qualitative and quantitative characteristics that make it different from the pattern of human disease previously caused by this virus. It has spread with enormous ease, affects almost exclusively adults, behaves as a sexually transmitted disease and focuses on very specific groups and transmission conditions. The high incidence in the city of Madrid in males that have sex with males (MSM) has allowed us to observe and report the experience with the first 30 cases diagnosed in our institution. Patients presented with febrile symptoms, genital and paragenital skin lesions reminiscent of smallpox, but less extensive and severe. The disease may also cause proctitis, pharyngitis and perioral lesions. The PCR test for diagnostic confirmation has been shown to be very sensitive and effective, not only in skin lesions but also in blood and other fluids such as pharyngeal, rectal exudates and blood. A very high proportion of patients with HMPX also have other sexually transmitted diseases that must be actively detected in this context. The spontaneous evolution of our patients has been good and hospitalization has been practically unnecessary. Transmission to non-sexual cohabitants and health personnel has been nonexistent and the lesions have disappeared in less than 30 days without leaving sequelae and no need for specific antiviral treatment.