Greater SP city halls mount war actions against dengue

City halls in Greater São Paulo have adopted strategies to fight dengue, some of them unprecedented for the region, in an attempt to reach places that are difficult to access.

While in the capital, which registered an increase of more than 200% in cases this year compared to 2021, a costal atomizer is used — a type of motorized equipment, which sprays the poison dispensed by a hose through a jet and turns into a fog curtain in contact with air.

In Santana de Parnaíba (Greater SP) a drone began spraying poison last Wednesday (17) over a lake.

In Santo André (ABC), Army War Shooting soldiers received training on the 9th. The city also trained nearly 800 brigade members against mosquitoes.

In all, practically the entire state has had actions against the mosquito and against the disease since the beginning of last week.

In São Paulo, the city hall uses a biological larvicide that, mixed with water, is placed in a container in the motorized equipment, which is used as a kind of backpack by the employee responsible for the application.

O Now witnessed the use of the equipment in a warehouse belonging to the city hall, in the neighborhood of Jaçanã (northern area), where the carcasses of vehicles that were collected after being abandoned on the streets of the neighborhood are piled up.

According to biologist Renato Sinnhofer Sugimoto, 41, who works at Uvis (Health Surveillance Unit) in Jaçanã, the machinery is used to release the larvicide in difficult-to-access places, such as in the yard, which has cars on top of it. the others. “The technique is important because it manages to reach places where it is not possible to see the larvae, such as between vehicles”, he says.

According to Sugimoto, the larvicide used is a bacterium, which needs to be ingested by the larva. However, the poison, which is diluted in water, does not have the power to eliminate the adult mosquito, which, in addition to dengue, can also cause chikungunya, zika and urban yellow fever.

“The use of this larvicide is mainly in water containers that contain larvae”, he says. “But it’s not like, ate and died, there’s a time for action.”

The biologist explains that the points considered potential for the survival of the larva, such as scrap metal, tire repair shops and recyclers, receive teams every 15 days, which is the time of the cycle between the larvae and adult stages.

According to data from the Epidemiological Surveillance of Arboviruses in the city of São Paulo, until November 3, 7,172 cases of dengue were registered in the city, an increase of 254% compared to last year.

The northern area of ​​São Paulo is where there are more confirmations of cases of the disease in 2021. According to the secretariat, the region had 1,874 cases. It is followed by the east zone with 1,701, the south zone with 1,540, the southeast with 1,200, west with 633 and, in last place, is the city center with 210 records.

Sugimoto affirms that the months before the hottest period are those in which attention should be doubled, not only at points considered to be potential for larvae infestation, but inside homes, avoiding keeping water standing on objects. “It is important to take action in the pre-summer period, to eliminate the breeding and reduce the number of larvae, thus avoiding the explosion of cases at the beginning of the following year.

Also according to the City of São Paulo, dengue usually has a cyclical behavior, with epidemic years (duration 1-2 years) and interepidemic years (duration 2-3 years). “In 2019, the last epidemic year of dengue in the capital, 16,815 cases were registered, a number 57% higher than that verified so far, which is 7,172”, says a note from the Municipal Health Department.

special drone

The municipality of Santana de Parnaíba acquired a drone to spray forest areas. The first test was carried out on Wednesday (17), when spraying was carried out in the Bacuri lake, in the Alphaville region, which has approximately 160,000 m².

According to the local city hall, the action, which is part of the “Xô Mosquito” program, is unprecedented in the region. The use of drones was inspired by Rio de Janeiro, which used the equipment to fight dengue in the Rodrigo de Freitas lagoon region, during the 2016 Olympics.

As in the capital, the larvicide used, which is a compound that does not harm the environment, is dumped in potential places for mosquitoes to breed.

According to the municipal secretary for the Environment and Planning, Veruska Carvalho, the objective of the action is to control the larvae, without harming the environment. “We found this year that there was an increase in the incidence of mosquitoes even before the summer,” he said. The city did not provide numbers for comparison purposes.

If approved, the pilot project with drone will be expanded to other regions of Santana de Parnaíba, according to the city.