Clinical Features, Antiviral Treatment, and Patient Outcomes: A Systematic Review and Comparative Analysis of the Previous and the 2022 Mpox Outbreaks

BACKGROUND: This study aims to comparatively analyze clinical features, treatment, and patient outcomes between the previous and the 2022 mpox (monkeypox) outbreaks. METHODS: Five bibliographic databases were searched for studies reporting clinical features, management, and patient outcomes of mpox. Systematic review and meta-analysis were performed. RESULTS: In total, 73 studies were included in the systematic review, of which 33 studies were subjected to meta-analysis. Previous outbreaks substantially affected children, whereas the 2022 outbreak primarily affected male adults, of which 94.66% (95% confidence interval [CI], 88.03–98.95) were men who have sex with men. Furthermore, 72.47% (95% CI, 51.04–89.71) reported high-risk sexual activity and the overall human immunodeficiency virus (HIV) prevalence was 37.65% (95% CI, 30.09–45.50). Skin lesions remain the typical symptom; however, their anatomic distribution differed. Systemic manifestations were common, but rectal pain was unique to the 2022 outbreak. The estimated overall fatality during past outbreaks in Africa was 4.61% (95% CI, 2.39%–7.35%), whereas 6.34% (95% CI, 3.35%–10.10%) of patients from the 2022 outbreak required hospitalization. Antiviral treatment, in particular tecovirimat, has been prescribed for a subset of patients, but the efficacy remains inconclusive. CONCLUSIONS: These findings are important for better understanding the disease and guiding adequate response to mpox outbreaks.