The beginning of March 2022 was marked by a large number of dengue cases, which remain high in this month of April. But during the last two years, in the Covid-19 pandemic, dengue cases have not been as high. The infectious disease doctor Guilherme Carvalho Freire, from Unimed de Franca, explains why the cases of dengue have “disappeared” in this period of Covid-19 and clarifies other doubts.
First answering the question of the supposed “disappearance” of dengue cases in previous years, the doctor Guilherme Freire explains that it is possible to understand this when evaluating the last years of the disease. “If we make an assessment over the last 20 years, it is possible to notice that every three or four years, we have a large increase in dengue cases. But this does not mean that in other years there were no cases of the disease. Last year, we had documented dengue cases in practically every month of the year, but they were sporadic cases, somehow controlled”, explains the infectious disease specialist.
In addition to this history of increasing cases every four years, Guilherme says that another issue is linked to the increase in rainfall. “Dengue is an acute viral disease and is already endemic. It is closely associated with its transmitter, which is the Aedes aegypti, which has the ability to reproduce in places where there is accumulation of water. For this reason, in the rainiest months – which in our region is at the beginning of the year -, the mosquito ends up replicating more, with greater chances of an increase in dengue cases. In the case of last year and the previous year, there were years when we didn’t have as intense rains as this year”, he says.
According to the doctor, the Covid-19 pandemic also contributed in a way to the lower number of dengue cases in France. “The movement of people from one region to another was less intense. This eventually caused the cases to decrease, because a contaminated person is bitten by a mosquito and this mosquito bites another person, who becomes contaminated”, explains Guilherme.
Another important factor during the pandemic pointed out by the doctor is the issue of people staying at home more. In this way, domestic care ended up being greater, with people cleaning their yards more and leaving less standing water.
A doubt that has been common about dengue in the social networks of the francans is about the “strength” that the disease has currently had. Some netizens even claim that the disease is “stronger” this time, and that this has been a result of the confinement of the pandemic, which would have left people more fragile. The infectologist denies this hypothesis and explains what may be happening in the case of these people.
“Dengue is closely related to the body’s capacity for inflammatory action. So, I do not believe that this issue of confinement may be causing more exacerbated demonstrations. This actually ends up not changing that power of response that much”, says the doctor.
Guilherme justifies that it is possible that dengue “with more intensity” may be associated with the subtype that has predominated in the region of Franca: “We have to remember that dengue has four subtypes circulating, and each epidemic can come with different subtypes. It has been described that subtype 1 has circulated more in our region, and in the last epidemic it was subtype 2. People have had more intense symptoms of body pain. This could be a characteristic of the virus that is circulating”.
Prevention is key
The infectologist says that it is difficult to make predictions for how long the dengue epidemic will continue in the region. Guilherme explains that the outbreak will be contained more quickly through collective work between public managers controlling vectors and monitoring, with the help of all citizens doing their part by taking care of their backyards and places where they identify standing water.
The main way to prevent the disease is not to keep stagnant water, which is a way to reduce mosquito breeders. Another form of prevention is the use of repellents to protect against mosquito bites. Wearing clothes with longer sleeves is also a form of prevention recommended by the infectious disease specialist.
The Department of Health of Franca guides that the population should seek a health unit for proper diagnosis and treatment. The Secretariat lists the following symptoms as the main ones: high fever – above 38.5°C -, intense muscle pain, pain when moving the eyes, malaise, lack of appetite, headache and red spots on the body.
Infectologist Guilherme warns that every suspected dengue must be notified to the Epidemiological Surveillance. In this way, the Surveillance is aware of possible creators of dengue and makes an active search in the region where the person made the call and that can minimize the creators of Aedes aegypti on site. The Health Surveillance of Franca assists the population by calling (16) 3711-9415.