Dengue: increase in the country is related to the climate crisis – 03/15/2024 – Balance and Health

The constant heat waves resulting from climate change associated with incomplete urbanization and the large movement of people in certain areas are favoring the expansion of dengue fever into the Brazilian interior.

According to a study by researcher Christovam Barcellos, from the Institute of Communication and Scientific and Technological Information in Health at Fiocruz (Fundação Oswaldo Cruz), recently published in the journal Scientific Reports, the disease has been spreading to the south and center-west regions of the country, where Historically the incidence is lower.

“In the interior of Paraná, Goiás, Distrito Federal and Mato Grosso do Sul, the increase in temperatures is becoming almost permanent. We had five days of heat anomaly, now there are 20, 30 days of heat above average throughout the summer. This triggers the dengue transmission process, both because of [da reprodução acelerada] mosquito and the movement of people”, explains Barcellos.

According to the article, the expansion of the disease in these regions is directly associated with the increasing frequency of extreme weather events, such as droughts and floods. The author also cites environmental degradation, especially in the cerrado, as an important influence.

There is already evidence that global warming, caused by human activity, has caused an increase in infectious diseases throughout the world, especially arboviruses, transmitted by mosquitoes. Records of autochthonous cases (which occur locally and are not brought from outside) of dengue in some European countries, such as southern France, Spain and Italy, are directly linked to climate change, according to researchers from the WHO (World Health Organization). Health).

It is the same case in Brazil, where experts still consider the disorderly growth of cities and the precariousness of services and basic infrastructure, such as sanitation and urban cleaning.

“In these regions that are suffering from high temperatures, we have also seen very accelerated deforestation. And within the Brazilian cerrado there are cities that already have heat islands, suburban areas or outskirts with poor sanitation conditions, making it more difficult to combat the mosquito”, adds Barcellos.

The study used data mining techniques to evaluate the association between thermal anomalies, demographic factors and changes in dengue incidence patterns over a 21-year period (2000 to 2020) in microregions of Brazil.

The article is also signed by researchers Vanderlei Matos, from Fiocruz, and Rachel Lowe and Raquel Martins Lana, both from the Barcelona Supercomputing Center, who have an agreement with the Brazilian institution through a technical cooperation partnership.