mosquitoes

We have been using DEET to repel mosquitoes for years. The only problem is that, done poorly, it’s their favorite food.

by

DEET is one of the ingredients most used in mosquito repellents. That makes us think that, as its name suggests, it repels these insects. He doesn’t like it. However, according to a new study published by Virginia Tech scientists, under certain circumstances, that same substance could become an attractant for mosquitoes. These circumstances, basically, are what occur when we apply repellents without reading the label. Today is a good day to start reading it. From repellent to attractant. These scientists they saw DEET generally repels mosquitoes. However, when they smell it while feeding, it can be associated with a reward. Something like what happened with Pavlov’s dog. When I heard the bell that was normally associated with mealtime, I would start to salivate. If mosquitoes smell DEET while feeding on blood, the next time they smell it they will associate it with food. And of course, they love that. A painful experiment. The experiments that were carried out for the publication of this study consisted of two phases. First, mosquitoes of the species Aedes aegypty in a cage connected to two bottles, one with clean air and one with DEET. Inside the cage there was a feeder with blood, from which they could have fed in two circumstances. First, with access only to the clean air vial and then with the DEET vial open, since the second vial was opened while they were feeding. In the second phase of the experiment, one of the researchers put his two arms into the cage, one with DEET and one without, and waited to see the behavior of the mosquitoes. Those who had blood-fed only with clean air went only to the arm without DEET. However, those who ate under the influence of DEET they preferred the arm with the repellent. just a little. In reality, the repellent effect of DEET is a reality. At adequate doses, it continues to repel mosquitoes. What has been seen in this study is that it becomes an attractive when they smell it in the background while feeding. Therefore, the problem is allowing them to feed while they smell it. A person who has too little, either because they have not applied enough repellent or because they applied it a long time ago, may not adequately repel the insect. It reaches your skin and feeds on your blood, while smelling a remnant. This remnant generates the aforementioned reward effect and, then, little by little you may stop disliking it. If every time we smelled the garbage they gave us 10,000 euros, would we still find it unpleasant? The importance of reading the label. Not all mosquito repellents have the same concentration of DEET. Therefore, you do not always have to apply the same amount or reapply at the same time. It is important to read the label, because if we use too little repellent or do not reapply it when necessary, we can generate the effect that was seen in the study. It’s not entirely clear. It should be noted that all this is not safe. This was seen in laboratory experiments. For now, it cannot be known if in reality, with DEET included in commercial repellents and mosquitoes flying freely, the same will happen. Furthermore, in the experiment the mosquitoes began to smell the DEET while they were already feeding whereas in real conditions the smell would be there from the beginning. More studies will have to be done, perhaps again with painful consequences for researchers and volunteers. Meanwhile, when in doubt, remember to read the labels carefully. Oh really. Images | NIAID In Xataka | Mosquitoes attack me in summer and I tried these TikTok tricks to get rid of them

Science already knows why mosquitoes attack you and not the one next door

by

With the arrival of summer, in addition to the heat, the hated mosquitoes also appear and do not hesitate to bite us during the day or night and leave us with a welt as a souvenir. But this also generates a lot of uncertainty in many homes, since of two people who sleep in the same room, the next morning, one is riddled with bites and the other is intact. What was thought. For decades, popular culture has attributed this phenomenon to having “sweet blood” or a certain blood group. However, science has left the guesswork behind to offer a much more precise answer by boiling it all down to the chemistry of our skin. The real magnet. The research that has marked a before and after in this field It was published in 2022 in the prestigious magazine Cell. In this article, after meticulously analyzing human skin odor, they discovered that people who are most attractive to species such as mosquitoes Aedes aegypti produce levels significantly higher carboxylic acids in the emanations of his skin. The most revealing thing about this finding is not only the identification of the chemical compound, but its persistence, since the study demonstrated that this chemical difference remains stable over the years. That is, our olfactory signature is constant and, if you are a magnet for mosquitoes today, it is very likely that your skin will continue to emit these same signals in the future. He is quite faithful. This biological mechanism is tremendously sophisticated, since, far from choosing their victims at random, mosquitoes are perfectly adapted to track down these compounds. A study published in 2023 in PLOS Neglected Tropical Diseases reinforced This is evidenced by analyzing the olfactory receptors of these insects, confirming that they are specifically designed to detect human carboxylic acids. Faced with this, deep-rooted myths such as blood group lose strength and although there is literature on the matter, current scientific evidence shows that it is a much more variable and noticeably less determining factor than our skin odor profile. There are more factors. As important as our body odor is, the attraction of mosquitoes does not depend on a single switch. As detailed a 2024 scientific review, The sting process is multifactorial and requires a precise combination of signals. Precisely, before smelling the acids on our skin, mosquitoes need to know that we are there. To do this, the carbon dioxide that we exhale when breathing and our body temperature act as the first long and medium distance location radar. Later, when the mosquitoes are already in our environment, the carboxylic acids in the skin come into play. There is more. Complementary variables related to the state of the host that wants to bite are added to this biological equation. For example, pregnancy has been identified as a context in which some people may be more attractive to mosquitoes, acting as an additional factor that adds to the individual’s basal chemistry. Image | National Institute of Allergy and Infectious Diseases In Xataka | Google is going to release 64 million mosquitoes with a curious mission: to eliminate mosquitoes

release 64 million mosquitoes

by

Eliminating disease-carrying mosquitoes is not an easy mission nor can it be carried out improvisedly. And if not, tell Verily, the subsidiary of Alphabet (Google’s parent company), which has been trying since 2017 with his DebugProject. How are they doing it? With artificial intelligence, robots and, as incredible as it may sound, with many, many mosquitoes. Verily’s latest move has been formally request to the United States Environmental Protection Agency permission to release up to 64 million mosquitoes over the next two years in the states of California and Florida. 64 million mosquitoes in your area. Verily has asked the EPA for authorization to release up to 32 million male mosquitoes of the species Culex quinquefasciatus bacteria carriers Wolbachia pipientis for two years in Florida and California respectively at a rate of 16 million the first year and another 16 million the next. At the time of this writing the public comment period was about to close (June 5). From that moment, the EPA makes the decision whether to approve it or not or whether to put conditions on the test. The objective of this mosquito bombardment that works as a biological pesticide is to obtain the necessary field data to, with EPA permission, market this pest control solution. Why is it important. The Culex quinquefasciatus mosquito is an old and feared acquaintance: it is the species responsible for transmitting the parasites of the avian malariaviruses West Nileof the rift valley fever and of the St. Louis encephalitis. West Nile virus is the leading cause of mosquito-borne illness in the continental United States, causing an average of 2,000 cases of illness per year and about 120 deaths. according to the US Centers for Disease Control and Prevention. On a global scale, the problem is greater: there is approximately 400 million cases of dengue per year and are estimated about 40,000 associated deaths. Finding a solution without chemical insecticides through biological control can be a true public health milestone with global impact. Context. There are compelling scientific reasons behind it: in Singapore, a clinical trial with more than 700,000 residents demonstrated that releases of mosquitoes with Wolbachia reduced the risk of dengue by more than 70%. Without going any further, the Debug Project free more than 10 million male mosquitoes per week in Singapore. In Fresno, California, between 7.5 and 14.4 million infected male mosquitoes were released between 2017 and 2018. The result was a reduction in the mosquito vector population of up to 93-95%. In detail. The mechanism behind this “biological pesticide” is relatively simple: only male (non-biting) mosquitoes that have been inoculated with Wolbachia are released. When they mate with wild females that do not have the same bacterial strain, the resulting eggs do not hatch. As several releases occur, the local population is reduced. And what does all this have to do with AI? Google uses artificial intelligence and automation to separate mosquitoes by sex, breed them and release them on a large scale and in a systematic way. Yes, but. All that glitters is not gold. The bacteria does not work with 100% reliability in all cases, as evidence this 2024 study where they concluded that between 6% and 75% of the eggs could produce live embryos under certain conditions. Come on, there is no guaranteed 100% sterility. On the other hand, in 2022 another study from the Verily/Debug team itself Google revealed that automated mosquito release systems were still in “prototype stages or very early versions.” In Xataka | We have spent years inventing everything to get rid of mosquitoes. Now we have a promising weapon: a laser that detects them and fries them In Xataka | Anti-mosquito repellents have been effective for 40 years. Now mosquitoes are learning to appreciate them Cover | National Institute of Allergy and Infectious Diseases and Karollyne Videira Hubert

Anti-mosquito repellents have been effective for 40 years. Now mosquitoes are learning to appreciate them

by

Summer is practically upon us and this means that mosquitoes are also beginning to be the order of the day. Here one of the great allies we have to spend a good night is the repellent that keeps mosquitoes away from our skin, but the problem is that now these little insects seem to have unlocked a new and disturbing achievement: relating repellent to the best place to bite. A new problem. A recent study published in the magazine Journal of Experimental Biology points out that the classic repellent made up of the synthetic molecule N,N-Diethyl-meta-toluamide It has stopped repelling mosquitoes and started attracting them. In this study, the researchers focused on the Aedes aegyptithe infamous mosquito yellow feverdengue and Zika. From here, what they did was design a highly controlled laboratory environment with meshes, heat sources that simulated human warm blood or sugar rewards. But they combined all these ideal conditions with the presence of the smell of repellent. The result. From several cycles of exposure to these environmental conditions, they could see that mosquitoes had the ability to learn and create an association between the repellent and the presence of a good place to bite. This means that if a mosquito dares to cross the barrier left by the repellent and manages to bite, or feed on sugar in this case, its brain is reprogrammed and the repellent goes from being a “danger” signal to a “there is food here” signal. In fact, the data showed that, after this conditioning, more than 60% of mosquitoes They went back to searching for the smell of the repellent, ignoring its original repulsive nature. It takes years. Although the jump to “attraction” is novel, the reality is that entomologists have been keeping the fly behind their ears for some time. Without going any further, in 2013 a study already showed that mosquitoes developed tolerance to repellents. In this case, it was found that three hours after a first exposure to DEET, the insects ignored the repellent. And now we know a little more about what exactly happens neurobiologically. You have to use it well. These results have occurred in a very controlled environment and forcing scenarios that are very specific with guaranteed rewards. But in the real world we find greater chaos and a mosquito that smells the repellent and cannot bite, because the concentration is high, it does not receive the “reward” of blood, so that learning is not consolidated. That is why researchers point to the need for the repellent to be applied within the time frame and in adequate concentration. But this does not mean that we do not have to redesign public health strategies adapting them to this plasticity that mosquitoes have, since we are not just talking about an annoying bite, but we are talking about the fact that the mosquito is a transmitter of very important diseases such as malaria or Zika. Images | Erik Karits In Xataka | Mosquitoes attack me in summer and I tried these TikTok tricks to get rid of them

Iceland was one of the last places on the planet that mosquitoes had not reached. That’s now history

by

For centuries, Iceland has held the ‘privilege’ of being one of the few habitable places on Earth where mosquitoes did not exist, something that can be a source of envy for many, especially with the arrival of summer. All thanks to its particular climate, with constant cycles of freezing and thawing that prevented the larvae from maturing, it acted as an insurmountable biological shield. However, climate change and human action have just broken down this barrier and this Icelandic ‘exceptionality’ has ended. The discovery. The history of this biological invasion starts in October 2025where Björn Hjaltason, a resident of the Kjós region noticed the presence of some unusual insects in his garden. From there he wanted to see them closer, and to capture them he used a fairly rudimentary method based on some ropes soaked in red wine. With this trap he obtained three specimens that were immediately sent to the Icelandic Institute of Natural Sciences, where the entomologist Matthías Alfreðsson confirmed the unthinkable: they were two females and a male. Culiseta annulataa species of mosquito common in Europe, but which had never managed to establish itself on the island of ice and fire. How have they arrived? Their disembarkation in the country may have been conditioned to different situations, such as travel aboard ships that came from Europe or even in the landing gear of commercial airplanes. All this, added to increasingly higher temperatures in Iceland, means that we are facing a major ecosystem problem. A hot Arctic. This very rudimentary discovery has served as a substrate for a profound analysis that has been published in the magazine Science, where it is noted that the appearance of mosquitoes in Iceland is only the symptom of a radical transformation throughout the Arctic. And global warming is affecting this region at breakneck speed, since the Arctic is warming four times faster than the world average. This thermal increase is not only allowing invasive species to survive the Icelandic winters, but is causing a serious biological imbalance throughout the boreal region. A domino effect. The arrival of mosquitoes and the alteration of the populations of native arthropods is not only a problem of annoying bites for its inhabitants or tourists, but it is a threat for birds. Here the early thaw is causing the peak of insect abundance to no longer coincide with the breeding season of waders, leaving them without their main source of food when they need it most. Furthermore, the large swarms of mosquitoes in arctic areas are already affecting the behavior of reindeer, which spend vital energy fleeing from the swarms instead of feeding, compromising their winter survival. That is why experts point to the need to control the arthropods that arrive in the region and, above all, a tracking system for these ecological changes that are so relevant. Images | Andreas M In Xataka | Mosquitoes attack me in summer and I tried these TikTok tricks to get rid of them

For the first time in history there are mosquitoes in Iceland. And it was assumed that they couldn’t get there

by

Iceland is being invaded. Not just for touristsbut because of something perhaps more undesirable: insects that had never been seen on the island. For the first time in their history, at least since records have been kept, Icelanders have encountered one of the bugs most undesirable and hated for all of us who have to sleep with the windows open in summer: mosquitoes. They have been few, but they can represent the advance of a full-fledged colonization. Unwanted guests. Bjorn Hjaltason is an amateur entomologist who was hunting for insects last week when he found something strange. On the wine-soaked rope he uses to catch moths and being able to observe it, three insects fell that have nothing to do with moths. They were mosquitoes, specifically two females and a male, but at first, Hjaltason described them as “some strange flies.” And as they count in BBCthe event was such that the local media opened with the news. Because yes, it is more serious than it may seem (and not because of the bites). Shelter. Iceland has remained one of the world’s mosquito-free bastions, one of only two mosquito-free havens. The other is Antarctica, and the reason is that these insects they don’t handle the cold well. Being cold-blooded, they need environmental heat to carry out their activity. When air temperatures are around 10º, their metabolism slows down so much that they become dysfunctional. Not only can they not fly, but they also cannot reproduce. In warmer climates, this is the time when they enter a kind of hibernation, looking for shelters in which to weather the storm until the heat returns. In Iceland it was not necessary because the average temperature was below 10º. BUT. Climate changethere is no more. Records from the Reykjavík observatory show that in the last 30 years there has been a gradual increase of temperatures, with average values ​​that have past from 2.4º to 4.1º. The average temperature has increased by 0.5º in the last decade, almost double of the planet average and there are areas that have broken all records. They are also occurring extreme episodeslike the 26.6º that in Córdoba would be pleasant and to go out with a jacket in the morning, but that in May of this year must have felt like real hell in Egilsstaoir. There were episodes like this before, but reports indicate that these events that were anomalies are becoming more common. You have to wait. Mosquitoes, of course, are at ease with those temperatures, but the big question is where they came from. Hjaltason found them in Kjós and speculates that they may have come on a freighter that landed at Grundartangi. The two cities are in western Iceland and the insect enthusiast points out that unusual ‘bugs’ usually come in those freighters. Another entomologist, Matthías Alfreodsson, to whom Hjaltason sent the mosquitoes confirmed that, although they belonged to a species that tolerates low temperatures somewhat better –Culiseta annulata-, they should not be in Iceland and we will have to wait until spring to check if the species has really established itself on the island. But Hjaltason is clear that if three of them went directly to his garden, “there will probably be more.” I feel sorry for you, fellow Icelanders. Images | Enzo Guidi In Xataka | The Japanese method to get rid of mosquitoes at home during the summer: katori senko

Elche suffers an annoying tiger mosquito pest. So you will release 2.4 million tiger mosquitoes to solve it

by

The tiger mosquito (Aedes albopictus) has become a problem in much of the territory in Spain. This insect has already settled in all the provinces of the Mediterranean basin and elsewhere in the Peninsula. The problem derived from this mosquito vector of diseases will go worse and is taking some administrations to take measures, some that perhaps do not seem too orthodox. Fire with fire. The City Council of the Alicante de Elche municipality has announced that it will release 2.4 million mosquitoes To fight the presence of the Tigre mosquito (Aedes albopictus) Between this year and the next one. The key is in the sterility of the specimens to be released. Aedes albopictus. The Tigre mosquito is originally from Asia, but it has already been established in Spain and other areas of Europe, especially in areas near the Mediterranean. This species, together with its “cousin” Aedes aegyptiwhose presence in Spain is limited, is a transmitter of some viruses, such as those that cause yellow fever, dengue, chikungunya and zika. Climate change and demographic changes, such as the progressive urbanization of some environments, is making it easier for risk species to prosper in new territories. This may be the case of these gender genre Aedes And also of others, Like the genre Culex responsible for transmitting the western Nile virus. Radical measures. This week, the City Council of Elche staged one of the loose ones that will be freeing thousands and thousands of insects. The objective is to release, between 2025 and 2026, 2.4 million sterile mosquitoes in an area that expands along 18 hectares. According to those responsible for the projectthe effects of this release will be noticed on a much larger surface, about 50 hectares, both agricultural and urban. Those responsible expect this technique to reduce the population of mosquitoes in the area by 80%. It may seem like a pilgrim idea, but the breeding and loose of sterilized insects to contain the population of a species is an implanted measure already in a variety of contexts is the call Sterile insect technique (TIE). The idea is that these sterile males appear with wild females to generate eggs that are not viable. A list that expands. In recent years there are numerous examples of administrations that have resorted to this strategy. One of the most recent examples We find it in Singaporewhere laboratories raise millions of specimens of the species Aedes aegyptiin order to fight dengue. These measures have also been implemented for years In countries like Australiawhere they are used to also combat malaria or zika. These types of techniques are used even with other insects Like the fruit fly. Also in Spain. We do not have to go so far to find examples of administrations that have resorted to this extreme measure. We don’t even have to leave the Valencian Community, where the pilot projects for the study of the TI At least until 2017. In 2023 It was announced the loose of nine million copies by the Ministry. A little hopeful panorama. A summer that is expected to happen to a rainy spring. It is the ideal cocktail for the appearance of various insects: mosquitoes, bed bugs, termites and even cockroaches. The expansion of certain insects can be a more or less important risk to the health of people that adds more mild inconveniences such as bites or material damage. But among all the risks derived from these animals, perhaps the role of mosquitoes as vectors of diseases is the most serious and among them the tiger mosquito is one of those that implies a more direct threatbecause it is one of the invasive species with the greatest implementation in the Peninsula and for the diversity of diseases with which it has been related. In Xataka | The Japanese method to get rid of mosquitoes at home during the summer: Katori Senko Image | James Gathany, CDC

Log In

Forgot password?

Forgot password?

Enter your account data and we will send you a link to reset your password.

Your password reset link appears to be invalid or expired.

Log in

Privacy Policy

Add to Collection

No Collections

Here you'll find all collections you've created before.