The COVID-19 pandemic has increased the interest in the use of wastewater-based surveillance (WBS) strategy for infectious disease monitoring, especially when clinical cases are underreported. The excretion of monkey virus (MPXV) in the feces of both symptomatic and preclinical individuals has further driven the interest in WBS applicability to MPXV monitoring in wastewater to support its mitigation efforts. We performed a systematic review with meta-analysis, using six databases to assess MPXV detection in wastewater. We performed a random-effects model meta-analysis to calculate the pooled prevalence at a 95% confidence interval (95% CI). Also, we carried out a subgroup analysis according to the country regions and a sensitivity analysis excluding studies classified as having a high risk of bias. The overall MPXV positivity rate in wastewater was estimated at 22% (95% CI: 14-30%; = 94.8%), with more detection rate in North America (26%, 95% CI: 8-43%) compared to Europe and Asia (22%, 95% CI: 12-31%). The MPXV detection rate was significantly higher in 2022 studies (22%, 95% CI: 13-31%) compared to 2023 (19%, 95% CI: 14-25%). The real-time PCR platform significantly detected more MPXV (24%, 95% CI: 14-34%) than the digital droplet PCR-based studies (17%, 95% CI: 4-31%), which was used less frequently. Viral concentration with centrifugation procedure indicated higher detection rates (21%, 95% CI: 10-33%) than other known sample concentration protocols. Generally, MPXV detection rates in wastewater samples strongly correlate with incidence cases of mpox (range of R = 0.78-0.94; < 0.05). Findings from this study suggest that WBS of MPXV could be employed as an epidemiological early warning tool for disease monitoring and mpox outbreak prediction similar to the clinical case-based surveillance strategies.
