Epidemiological and clinical characteristics of Mpox Cases in Serbia in 2022

INTRODUCTION: Mpox viral infection, previously known as an endemic zoonosis typical for West and South Africa, appeared in the Republic of Serbia in early summer among young and middle-aged men, particularly Belgrade's citizens. The aim of this study is to evaluate the epidemiological and clinical characteristics of Mpox cases registered in Serbia in 2022. METHODS: We conducted a national observational study using the national surveillance anonymized data of people who met case definition criteria on Mpox infection and confirmation by the polymerase chain reaction method. Clinical data were collected by standardized case investigation form used for epidemiological and clinical evaluation of cases. RESULTS: A total of 43 cases reported from the 17th of June to the 5th of October 2022 were men, aged between 20 and 54 (median age, 35 years), 74,4% living in Belgrade. Three-quarters of cases reported sex with other men as a potential disease transmission route. Out of the total, 15 (34,9%) Mpox cases had HIV co-infection. HIV-positive patients were older than negative cases (p = 0,023). The mean incubation period among patients who reported exposition to a probable or confirmed case was 9,3 (2-22) days. The most common systemic symptoms were fever (86%) and lymphadenopathy (44,2%). Three patients with common symptoms of fever were hospitalized. All cases presented a rash, mostly in pustule form (90,7%). The dominant localization of the skin lesions was the anogenital region (62,5%), whereas 9,3% of the patient's lower extremities were affected. CONCLUSIONS: In Serbia, the outbreak of Mpox infection affected young and middle-aged men, mainly situated in the capital of Serbia. The disease had a polymorphic presentation, including a characteristical rash of the anogenital region implying the main transmission route. KEY MESSAGES: • Health promotion and community engagement regarding Mpox are very important in large urban settings. • Risk communication should be prioritized to promote safe sexual practices in vulnerable populations.