Indicators of InfoDengue, the arbovirus monitoring system developed by researchers of Fiocruz and of the Getúlio Vargas Foundation (FGV), show that the South Region of the country is worthy of attention in 2022, with a trend of increased dengue activity as it expands into higher latitudes. Important dengue fever outbreaks occurred in the regions of Londrina (PR), Sengés (PR) and Joinville (SC) last year and in the previous years, which may indicate that the vector is adapting to climate changes, a subject that requires additional studies. InfoDengue is already developing a project to evaluate changes in temperature patterns in the country and possible association with an increase in the dengue fever season.

“It would be important to foment research projects in the field of entomology to study behavior changes of Aedes aegypti”, explains Cláudia Codeço, InfoDengue coordinator. Simultaneously hot and rainy periods facilitate the proliferation of the Aedes aegypti mosquito, which transmits the viruses that cause dengue fever, zika, and chikungunya. Reports of dengue fever outbreaks in Brazil have existed since 1846, but it was in 1986 that is reemerged and rapidly spread around the country, becoming a reason for concern and a constant alert in terms of public health. “The transmission period is coming earlier in some states, which is reason for concern and may lead to high incidence of cases if no adequate control of the vectors is achieved”, states the researcher. 

According to InfoDengue indicators, in addition to the South of the country there are other areas currently worthy of attention: the north-west part of São Paulo/SP, the area between Goiânia/GO and Palmas/TO, including the Federal District/DF, and some isolated municipalities in the states of Bahia, Santa Catarina and Ceará.

InfoDengue researchers also show a pattern of dengue fever in Brazil in 2021, especially in the western part of the country, from Acre to Mato Grosso, which has contributed to a high circulation of the virus in neighboring countries, such as Bolivia and Paraguay. This highlights the importance of a strong and articulated surveillance in the borders. The city of Rio Branco, capital of the state of Acre, suffered with an intense epidemic with high impact on the population, already undermined by the floods that occurred in the same period. 

In the winter months of 2021 there was an atypically increased activity of dengue fever in the North-East Region. One possible explanation was the circulation of chikungunya in the region. “The two diseases have similar clinical characteristics, especially in their early stages, which makes it harder to classify them based mainly in clinical-epidemiological criteria. This means that part of this dengue activity comes from a difficulty in making a differential diagnosis. It shows the importance of strengthening laboratory surveillance in the country, with the implementation of sentinel surveillance for arbovirus diseases”, alerts Codeço.

In the spring months of 2021 there was a significant and early growth in the curve of dengue fever in the center-west region (states of MT, GO and DF) and along the Brasília-Belém highway, passing through Palmas/TO and the south of the state of Pará, a region that should be monitored closely as it is featuring an early pattern of dengue circulationn. In 2021 the state of São Paulo also faced increased dengue activity in its north-west region, in the capital, and in the Santos basin.

The scenario presented by InfoDengue highlights the importance of observing mosquito behavior and of keeping it under control to avoid dengue hotbeds and combat the vector.

InfoDengue

The InfoDengue system currently monitors data regarding dengue, zika and chikungunya all over the country, in an integrated fashion, analyzing epidemiological compulsory report data, climate data, and mensions to diseases on social media, correcting the delay in notifications to speed up the decision-making process. Reports are sent to health secretariat offices on a weekly basis, containing all this information.

InfoDengue app

With the goal of optimizing the time of the users of InfoDengue, the online monitoring system of arbovirus diseases, project coordinator and researcher/professor of the FGV School of Applied Mathematics, Flávio Coelho, developed the first InfoDengue app for Android and iOS, as he noticed an increase in the number of mobile accesses to the website. With the app users can search the status of arbovirus diseases in the region they want.