What are the effective techniques to repel mosquitoes?

Insect of the summer, the mosquito is the cause of irritating bites and can in some cases transmit diseases. A veritable arsenal exists to combat them, but not all methods are equally effective.

With the return of the heat each year comes the season of the mosquitoes, their nocturnal buzzing, their bites and all the inconveniences that follow. To fight against this insect, an arsenal of means is available in pharmacies or even in the new technologies section, but in the lot, all the products do not have the same effectiveness in repelling this individual.

In addition, “no single measure is 100% effective. It is the sum of individual and collective actions that reduces the number of mosquitoes, their circulation and the number of infections they transmit”, underlines the Health Insurance.

• Effective skin repellents

The most well-known ways to fight against mosquitoes are in the form of creams or sprays with repellent properties, intended to keep away these insects which can transmit dengue fever, chikungunya and zika.

It is “recommended to use skin repellents on bare body parts to protect yourself during the day or evening”, explains the Health Insurance. To be effective, these products must contain DEET (N,N-Diethyl-m-toluamide) – contraindicated in pregnant women and children under two years of age – or IR3535 which “can be used in child from 6 months or pregnant women but at lower concentrations”.

The magazine What to choose also points out that it is difficult to know the effectiveness of a product before application, because it depends on its composition. He notes, however, that “the most effective mosquito repellents are based on DEET at concentrations of 25%, 30% or even 50%”.

These products remaining toxic at high doses, the Ameli site advises to choose rather “repellents in cream or lotion to repellents in spray, because of the risk of inhalation or ingestion during their application”, and to avoid any application. on wounds or irritations.

“The application on the face must be carried out without direct application”, also underlines the Vidal, and for the product to be effective, “it is necessary to privilege the application in the morning and in the evening, periods when the insect vectors of diseases are the more active.”

The duration of these protections on the skin fluctuates “according to their concentration of active substances”, writes Ameli. It “varies from 4 to 8 hours”, writes the PACA Regional Health Agency, stressing that “the application must be renewed after a swim”.

• A mosquito net to keep the insect away

These nets with very small holes make it possible to create a bubble of protection without having to resort to chemical products. L’Assurance Maladie advises to install them on doors, windows, and other entry ways, but also on beds and cradles.

The city of Strasbourg has also distributed mosquito nets to certain inhabitants, which are placed over the water points in the gardens, in order to prevent mosquitoes – in particular the tiger mosquito – from laying eggs there, because their larvae develop in the stagnant waters.

It is also recommended to wear covering clothes to avoid bites on the arms and legs.

For even more effective protection, Ameli recommends impregnating mosquito nets with insecticides, “permethrin or a combination of deltamethrin + transtetramethrin”.

• Insecticides to eliminate them

Insecticides are not intended to repel mosquitoes, or keep them away, but to kill them.

What to choose emphasizes the “dreadful effectiveness” of these sprays, explaining that “on the labels, in the ‘composition’ paragraph, the chemical substances of the pyrethroid family can be identified by their name which ends in ‘-thrin’ (transfluthrin, tetramethrin… )”. However, the magazine recalls that these products “use active substances that are harmful to health, so they should be used in moderation”.

In the same category, the electric diffusers that plug in are not always effective according to the magazine, “moreover, they diffuse insecticide continuously, we breathe it all night long”.

The Health Insurance site also cites the effectiveness, less important but existing, “of electric rackets inside homes”, “air conditioning and ventilation which also reduce the risk of stings” and “spirals anti -mosquitoes or ‘smoke streamers’ outside or in verandas”.

• Mosquito traps installed in cities

Several cities have installed mosquito traps in public outdoor areas, which come in different forms but reproduce the same system: attract the mosquito and trap them.

These terminals will “simulate the breathing of a human being because it is the main point of attraction of the mosquito”, explained in June on BFM Marseille Pierre Bellagambi, president and CEO of QISTA, which manufactures one of these terminals. According to him, they can catch from 200 to more than 7,000 mosquitoes a day in areas where there are many.

“Our machine will emit the same molecules as you and me when we are active, and when the female mosquito is nearby she will be attracted” and trapped in the object, which will “prevent her from laying her two hundred eggs every 48 hours”, he explains, stressing that it is “a complementary tool to traditional methods, its advantage is that it is constantly outside”.

Whether What to choose notes the effectiveness of systems of this type for individuals in order to “reduce the population” of mosquitoes, the magazine specifies that “female mosquitoes will always go first to people to take their blood meal rather than to the trap”.

• Prevention to avoid proliferation

Health authorities insist a lot on the fact that to avoid the proliferation of mosquitoes in one place, you have to attack the source. “It is important to cover, throw away and empty all containers that may contain water”, underlines the prefecture of Ain, because this is where the females lay eggs and the larvae develop.

“Saucers, vases and buckets should be emptied once a week, and flowerpot saucers filled with wet sand. These simple actions can effectively reduce the risk of mosquitoes near your home” , explains the prefecture.

The “mosquito likes to lay eggs in very small damp places”, explains to BFM Alsace Françoise Schaetzel, vice-president of the Eurometropolis of Strasbourg, who calls for “raising awareness of what are called good gestures”.

In Wantzenau (Bas-Rhin), the mayor explained last summer to BFMTV that the city was setting up, in parallel with solutions such as mosquito traps, “areas for bats”, and was doing a “reintroduction more massive swallows”. These two animals are mosquito predators, which would also allow upstream to reduce the population of this insect on site.

• What does not work at all

In its list of products to fight against mosquitoes, the Health Insurance also points to several methods which do not work at all to avoid mosquito bites: ultrasound devices, “ribbons, sticky paper and stickers without insecticide”, “anti-insect bracelets against mosquitoes and ticks”, essential oils – which have an “effectiveness generally less than 20 minutes” -, vitamin B1 and homeopathy.

“With the exception of citriodiol, all natural plant-based products must be given up, whether they are extracts, essential oils or lemongrass: they do not protect”, writes for his part. What to choose.

It is also important to remember that it is not a question of overcoming all mosquitoes, of eliminating them completely, but of keeping them away or regulating their population in order to avoid bites which could transmit diseases. As a reminder, the mosquito has an important place in the food chain, and serves as food for many species such as fish and birds.