Climate variables and confirmed dengue cases in an urban area of Peru

Abstract

Introduction: increases in temperature and precipitation are associated with a higher risk of vector-borne diseases, such as dengue. In the Peruvian Amazon rainforest, the epidemiological complexity of dengue requires identifying local climatic predictors for surveillance. Several studies have shown associations between climate and dengue, but local evidence in Ucayali is limited.

Objective: to analyze the relationship between climatic variables and confirmed monthly dengue cases in Callería, Yarinacocha, and Manantay, Ucayali, Peru, during 2018–2023.

Method: retrospective and descriptive study. Confirmed cases were obtained from the Epidemiology Office of Ucayali; data on maximum temperature, minimum temperature, and total precipitation were obtained from the National Meteorology and Hydrology Service of Peru. Monthly averages were organized, and simple and multiple linear regressions were applied.

Results: 23,002 cases were recorded; 2023 accounted for 6,892 and 2018 only 249. Maximum temperature was not a significant predictor (adjusted R²=0.02; p=0.28). Minimum temperature explained 44.7% of the variability (adjusted R²=0.44; p=0.01; Beta=0.70), and total precipitation explained 31.2% (adjusted R²=0.31; p=0.034; Beta=0.61). The multiple model reached adjusted R²=0.66; precipitation (p=0.04; Beta=1.37) and maximum temperature (p=0.04; Beta=0.86) were significant. Minimum temperature lost significance (p=0.44). The model was globally significant (F=6.44; p=0.01).

Conclusions: minimum temperature and precipitation are climatological factors predictive of dengue incidence. This information is crucial for strengthening epidemiological surveillance programs and guiding prevention strategies that consider climatic variability in dengue risk management in Ucayali.