Estimando el efecto del cambio climático sobre el riesgo de la enfermedad de Chagas en Chile por medio del número reproductivo

Abstract

Effects of climate change on reproductive number of Chagas disease Background: Reproductive number (R 0)-maps estimate risk zones of vector-borne diseases and geographical distribution changes under climate change. Aim: To map R 0 aiming to estimate the epidemiological risk of Chagas disease in Chile, its distribution and possible changes due to the global climate change. Material and Methods: We used a relationship between R 0 and entomological parameters of vectors as function of environmental variables, to map the risk of Chagas disease in Chile, under current and projected future environmental conditions. Results: We obtained a geographical R 0 estimation of Chagas disease in Chile. The highest R 0 averages correspond to the Central-Northern regions of Chile. T. cruzi transmission area could increase in the future due to climate changes. Independent of the future condition, both for optimistic and pessimistic climate change scenarios, the area of potential risk for Chagas disease transmission would increase. The estimated R 0 values suggest that, if a control of T. infestans is not maintained, Chagas disease endemic status will persist or increase, independently of the climate change scenarios. Conclusions: Mapping R 0 values is an effective method to assess the risk of Chagas disease. The eventual increase in the transmission area of the disease is worrisome. (Rev Med Chile 2019; 147: 683-692)