MercoPress. South Atlantic News Agency

PAHO and Argentine authorities join forces to tackle dengue crisis

The Aedes Aegypti mosquito has grown immune to some insecticides due to the overuse of these chemicals

Argentine health authorities and the Pan American Health Organization (PAHO) have joined forces to devise a strategy to tackle the outbreak of dengue fever after at least 315,000 cases have been confirmed so far this year, it was reported in Buenos Aires.

”As part of the strategies for a comprehensive approach to the problem of dengue, workshops oriented to Integrated Vector Management (IVM) and public outreach activities were carried out in order to contribute to the community awareness campaign regarding the identification and reproduction and life cycle of the Aedes aegypti vector,” PAHO said in a statement.

PAHO Directorate of Vector-Borne Disease Control issued a communiqué through its local office, explaining that a team from the regional agency had participated in training activities for healthcare professionals in the province of Chaco. The federal Health Ministry announced another course in Misiones.

Argentina's National Epidemiological Bulletin (BEN) April 21 release mentioned 315,942 dengue cases in the first 15 weeks of the year, tantamount to 94.85% of the 333,084 infections recorded since Epidemiological Week 31 of 2023.

“Compared to other epidemic years, the current season is characterized by greater magnitude than previous epidemic seasons: the accumulated cases up to SE15 represent 3.17 times more than what was recorded in the same period of the previous season - 2022/2023 - and 9.1 times more than what was recorded in the same period of 2019/2020,” the BEN read.

In regional terms, cases of the disease transmitted by the Aedes Aegypti mosquito have increased to 5.2 million in 2024, with some 1,800 deaths reported. PAHO Director Jarbas Barbosa said in a press conference that Brazil and Argentina still have a “very strong” transmission rate.

On a brighter note, the BEN mentioned 36,681 new cases for the first week of April, compared to 52,466 the previous week.

According to experts, the dengue mosquito will not be extinguished despite the nearing cold weather season. Although egg hatcheries will not replicate, the mosquito will not stop circulating due to climate change and other factors affecting these insects' life cycle.

Argentine scientists in the Patagonian province of Neuquén and at the National Center for Diagnosis and Research in Endemoepidemics (CeNDIE), ANLIS Malbrán found that the mosquitoes are now resistant to insecticides. CeNDIE Director Mariana Manteca Acosta told NA that municipalities nationwide were being warned about the impact of the wrongful use of insecticides, which are not the proper way to control dengue. In her view, other community strategies focused on the mosquito's breeding cycles were needed.

“Insecticides should not be used on a large scale because mosquitoes are also exposed to other insecticides, such as those in agriculture, and with the study, we began to detect that there are degrees of resistance due to several factors. That is why it is requested that they only be applied during outbreaks, and not as a preventive measure as soon as the first mosquitoes appear because the insecticide is not water,” she explained.

“It is understood that the population asks for fumigation because it is what is known, but the misuse or overuse of insecticides and applied at times when it is not needed makes these mosquito populations begin to have this resistance and that is why there are places in the country where there is a lot of resistance and others where it begins to show and in those places the insecticide kills, but only a group of the population, not all of them,” she added.

Insecticides “kill the adult mosquito, but you have to know when to spray” them. “One thing we recommend is to attack the immature stages, which are the larvae, and thus avoid potential breeding sites,” she underlined. “A potential breeding place is any object that accumulates water and that is what must be avoided,” she insisted.