Experts recommendations to protect us from zika and other diseases like dengue or chikungunya, which affect most of our region, is to use mosquito repellent. This, in addition to other precautions (wear clothes that cover our arms and legs, cover water tanks or swimming pools and leave no water remaining when watering the pots), will help us to keep the Aeades aegypti, the main transmitter of these diseases , at bay.
But what repellent should you use? Do they all have the same effectiveness?
The simplest answer is no. According to a new study published in the Journal of Insect Science by researchers at the University of New Mexico in the United States, none of the 11 products they tested were 100% effective.
However, the ones that obtained the best results are two: aerosols containing DEET and those with lemon Eucalyptus oil (OLE). These products, says the study, reduced the attraction of mosquitoes by 60%.They do not work.
The researchers tested repellents by placing a "human bait" inside a wind tunnel near a mosquito cage. Thus, the researchers studied how close the mosquitoes were to the person inside the tunnel, which they protected with different repellents for a period of 15 minutes.
Citronella candles, for example, demonstrated a null effect. Moreover, they showed the opposite effect, according to the researchers, although this negative difference was not large enough to be considered significant. Portable protection methods, such as wristbands, were completely ineffective. This may be, scientists say, because the amount of repellent they contain is not enough.
The only device that showed results was a portable mosquito repellent OFF! Which distributes the insecticide (metofluthrin) around who uses it without needing to apply the repellent directly on the body. According to Stacy Rodriguez, director of the molecular vector physiology laboratory at New Mexico State University, the result of this study "is extremely important because consumers need to be aware that mosquito repellents are not available" .
"While the labels on many products have very strong assertions, some products simply do not work," added the researcher.Frequent application
Other devices tested were those that work with sound waves. They say they drive away mosquitoes with audible sound waves for insects but we can not hear them. As expected, they also proved to be completely inefficient. "At times when vector-borne diseases such as zika are a real threat, the most serious danger the consumer is facing is the false reassurance that some repellents protect him against Aeades aegypti when they do not really offer him any protection", conclude the authors of the study.
Anyway, it is important to remember that insects repellents should be applied frequently and it is important to do so after spraying with sunscreen, otherwise the latter can decrease the effectiveness of the repellent. Most anti-mosquito products are safe for pregnant women, but they should consult a doctor before using them. And, those products contain lemon Eucalyptus oil (OLE) should not be used in children under three years of age.