Dados do Trabalho

Título

Influence of climate change on the expansion of dengue in an urban area endemic of the disease

Introdução

Dengue is one of the most important arboviruses in the world, with currently around 2.5 billion people at risk of becoming infected, mainly in tropical countries. Thus, understanding the factors that interfere in the expansion of dengue is of fundamental importance to direct the actions of the Control Program, including abiotic ones, aiming to reduce the incidence and lethality of the disease.

Objetivo(s)

The present study evaluated the incidence of dengue and the influence of climatic variables on the number of cases in an urban area endemic for the disease.

Material e Métodos

A time series study of cases was carried out with all confirmed cases of dengue in the municipality of Belo Horizonte of 1996 to 2021. The 12 climatic explanatory variables were obtained from the National Institute of Meteorology, namely: total precipitation, maximum temperature, minimum temperature, average temperature, rainy days, precipitation/rainy days, precipitation in the dry period, maximum temperature in the dry period, temperature minimum dry season, rainfall in the rainy season, maximum temperature in the rainy season and minimum temperature in the rainy season. The analysis was performed using multiple linear regression.

Resultados e Conclusão

Was observed five epidemic peaks of cases in the evaluated period, being them in 1998, 2010, 2013, 2016 and 2019 with incidence rates of 4086.02 (1998), 2175.90 (2010), 3879.21 (2013)), 6199.40 (2016), and 4596.05 per 100,000 inhabitants (2019). From the second decade of the analyzed period (2006-2021) the frequency of dengue epidemics increased, occurring at 3-year intervals (2010, 2013, 2016 and 2019), whereas previously it was only an interval of 12 years. It was observed a correlation between number of cases and increase of the maximum annual temperature. The epidemic outbreaks occurred in years with the maximum total temperature above 27°C and the maximum temperature of the dry seasons above 26°C. Although precipitation variables were included and evaluated in the study they did not turn out significantly correlated with the increase of dengue cases. Our results suggest that the re-emergence and emergence of new serotypes, although important in defining epidemic years, cannot be considered as the only determinant of epidemic years, requiring a combination of climatic conditions that provide an increase in the population of vector insects and the transmission of the virus.

Palavras-chave

Dengue; climate effects; incidence.