Brazil's Dengue Outbreak May Continue for Years

According to recent reports from South America, infectious diseases may continue spreading in late 2023.

A new study forecasrs a 20% increase in dengue, Zika, and chikungunya cases over the next 30 years. Higher temperatures are already causing the diseases carried by the Aedes aegypti mosquito to spread in cooler regions like southern Brazil and southern Europe.

A study conducted at the University of Michigan concluded after analyzing the incidence of these mosquiuteo-transmitted diseases in Manaus, Recife, Rio de Janeiro, and São Paulo, Brazil.

"Brazilian health agencies need to be prepared not only for the increased incidence of diseases like dengue and Zika but also for longer transmission seasons and broader geographic areas of occurrence," affirms epidemiologist Andrew Brouwer, co-author of the study and researcher at the University of Michigan School of Public Health.

According to Brazil's Center for Arbovirus Emergency Operations, 635 fatal dengue cases had been reported by June 11, 2023, an increase of 22% compared to the same period in 2022.

The agency's most recent update, released by the Ministry of Health, shows 1.3 million probable dengue cases so far this year, while the total number for 2022 was 1,450,270 cases.

The study also showed more potential for Zika epidemics than current levels in all the analyzed climatic scenarios, where the threat had been expected to drop because of extreme heat.

Zika and dengue spread most quickly at average daily temperatures around 30° Celsius, but outbreaks are still possible at 35°C.

As of August 24, 2023, two dengue vaccines are available in certain countries. However, there are no approved Zika vaccines available.