Mapping global zoonotic niche and interregional transmission risk of monkeypox: a retrospective observational study

Abstract

Abstract Background: The outbreaks of monkeypox have been ongoing in non-endemic countries since May 2022. A thorough assessment of its global zoonotic niche and potential transmission risk is lacking. Methods: We established an integrated database on global monkeypox virus (MPXV) occurrence during 1958−2022. Phylogenetic analysis was performed to examine the evolution of MPXV and effective reproductive number (Rt) was estimated over time to examine the dynamic of MPXV transmissibility. Potential ecological drivers of zoonotic transmission and interregional transmission risk of MPXV were examined. Results: A total of 49 432 human patients and 20 kinds of animals with MPXV infections were reported in 78 countries as of July 24, 2022. Based on 525 whole genome sequences, two main clades of MPXV were formed, of which Congo Basin clade has a higher transmissibility than West African clade before the 2022-monkeypox, estimated by the overall Rt (0.81 vs. 0.56), and the latter significantly increased in the recent decade. Rt of 2022-monkeypox varied from 1.14 to 4.24 among the 15 continuously epidemic countries outside Africa, with the top three as Peru (4.24, 95% CI: 2.89–6.71), Brazil (3.45, 95% CI: 1.62–7.00) and the United States (2.44, 95% CI: 1.62–3.60). The zoonotic niche of MPXV was associated with distributions of Graphiurus lorraineus and Graphiurus crassicaudatus, richness of Rodentia, and four ecoclimatic indicators. Besides endemic areas of Africa, more areas of South America, the Caribbean States, and Southeast and South Asia are ecology-suitable for MPXV occurrence once the virus invades. The majority of Western Europe have high-imported risk of monkeypox from Western Africa, whereas France and the United Kingdom have potential-imported risk of Congo Basin clade MPXV from Central Africa. Among the top 15 countries with high MPXV-imported risk from main countries of 2022-monkeypox outbreaks, eleven of them were located at Europe with the highest risk in Italy, Ireland and Poland. Conclusions: The suitable ecological niche of MPXV is not limited to Africa, and the transmissibility of MPXV during the 2022-monkeypox outbreaks significantly increases. European have higher imported risk both from endemic areas and current epidemic countries. Future surveillance and targeted intervention programs are needed in its high-risk regions informed by updated prediction.