Epidemiology, clinical presentation and outcome of human mpox in Rivers State, Nigeria during the 2022-23 outbreak: an observational retrospective study.

Introduction: limited studies describe the epidemiology, clinical presentation, and outcome of mpox in Rivers State, Nigeria. Methods: an observational retrospective study of suspected mpox cases seen between October 21, 2021, and April 30, 2023, at the University of Port Harcourt Teaching Hospital, Rivers State, Nigeria. Laboratory confirmation was by qPCR testing of skin swabs, or crust samples. A data extraction form was used to obtain sociodemographic and clinical data. The primary outcome was the rate of hospitalization and death. Data was analyzed using IBM SPSS version 25. A p-value of <0.05 was considered statistically significant. Results: of 35 participants, 24 (68.6%) were males with a mean age [standard deviation] of 33.7 (± 9.9 years), and 5 (14.3%) had HIV infection. The majority (n=33, 94.3%) reported being in a heterosexual relationship with a household identified as the probable place of contact (n=13, 72.2%). None of the patients reported contact with animals or a travel history. The most common symptoms were skin rash (35, 100%), followed by fever (26, 74.3%), and fatigue (26, 74.3%). Concomitant varicella zoster virus infection (n=6, 17.1%), hospital admission (n=28, 80%), and death (n=3, 8.6%) were observed. There was a statistically significant association between mortality and patients with HIV (p = 0.002). Conclusion: the 2022-23 mpox outbreak in Rivers State predominantly affected young adults and was characterized by human-to-human transmission and typical febrile rash syndrome with an association between mpox mortality and HIV infection. Targeted public health interventions are needed to control the spread of mpox in Nigeria.