Epidemiological findings and estimates of the instantaneous reproduction number and control strategies of the first Mpox outbreak in Latin America

Abstract

AbstractBackground and objectivesince 2022, the world has experienced the largest Mpox outbreak in history. The region of the Americas has been especially affected, accounting for 67% of the cumulative cases worldwide. Key epidemiological characteristics of the outbreak for the Latin American region remain understudied. Here we provide estimations of R(t) and describe the key epidemiological trends, and vaccination strategies of the Mpox outbreak in six Latin American countries.Materials and methodswe investigated the public health response to the Mpox outbreak in six Latin American countries from official sources. The surveillance data were obtained from the official Mpox report of the Pan American Health Organization. We calculated cumulative and incident confirmed cases according to the report date for each country and represented these findings in epidemic curves. The R(t) was estimated on weekly sliding windows for each country.ResultsThe maximum means of R(t) ranged from 2.28 to 3.15 from May to July 2022. At epidemiological week 42, the R(t) estimates were as follows: Argentina: 0.94 (95% Credible interval -CrI-0.77 to 1.12), Chile: 0.83 (95% CrI: 0.64 to 1.05), Colombia: 0.60 (95% CrI: 0.52 to 0.69), Mexico: 0.75 (95% CrI: 0.67 to 0.84). For Peru and Brazil, R(t) decreased to less than 1 in weeks 32 and 33, with estimates between 0.89 (95% CrI: 0.82 to 0.96) and 0.94 (95% CrI: 0.89 to 0.98), respectively.Conclusionour results provide relevant information about current trends and future scenarios of the Mpox outbreak in Latin America. From late August to early September 2022, R(t) started to decrease to values less than 1, despite the limited delivery of vaccination programs implemented across the region. However, a large population remains at risk, and there is a possibility of new waves of the disease as the epidemic continues its course.