Case report of Usutu virus infection in an immunocompromised patient in Italy, 2022.

Usutu virus (USUV) is an arthropod-borne flavivirus emerged in Africa in 1950s and in Eruope in 1990s causing a massive number of birds' deaths. The role of USUV as human pathogen has been only recently hypothesized and cases of USUV infection in humans remain limited and often related to immunocompromised subjects. Herein, we report a case of USUV meningoencephalitis infection in an immunocompromised patient with no history of previous flavivirus infection. The infection due to USUV evolved rapidly since hospital admission thus resulting fatal in few days after symptoms onset and, although not proven, a suspected bacteria co-infection has been hypothesized. Based on these findings, we suggested that when USUV meningoencephalitis is suspected in countries endemic, careful attention should be applied to neurological syndromes during summer months especially among immunocompromised patients.