Research suggests that specific individuals really are more attractive to mosquitoes due to particular skin odors. These smells, produced by fatty acids present in sebum (the oily compound that moisturizes skin), impact mosquito behavior.
Some individuals are more appealing to mosquitos than others, and brand-new research study is beginning to show why. This Reactions episode dives into the chemistry of the particles on our skin that make a few of us a lot more appealing to these pesky pests. It likewise exposes which items we can use to attempt to discourage them.
Video Transcript:
Are you a mosquito magnet?
Because I am a mosquito magnet. Mosquitoes love me. A mosquito would bite me no matter my pronouns.
I swear there can be 8 individuals at a barbecue and every mosquito makes a beeline directly to me, like I am their individual barbecue. That is why I have indoor barbecues, not recommended by the American Chemical Society.
And guess what? We are not envisioning it if youre a mosquito magnet. There is actually something that makes us more appealing to mosquitoes, at least.
I constantly said pro-bos-kis when I worked in a Drosophila lab and it does seem that thats a valid pronunciation, but a pro-bos-sis is more accepted.
Before we enter into why mosquitoes enjoy particular individuals more than others, lets stroll through what occurs when these mini-vampires suck your blood.
When a female mosquito arrive on you, due to the fact that it is just the females that bite, it inserts its proboscis into you. This proboscis is a small mouthful of 6 needles that saw their method into your skin.
Two of the needles are serrated like a saw blade, however the proboscis is shaped in a manner to lessen discomfort so that you do not right away knock the mosquito off.
There is a soft part that strikes you first, and after that the sawing action is combined with a light vibration so that less force is needed.
Some researchers are in fact trying to create likewise formed microneedles for more painless injections, which sounds good.i So I guess mosquitoes are finally doing something helpful for society.
Anyway, mosquitoes dont simply suck your blood. They actually inject a few of their saliva into you also.
And while scientists are still attempting to tease apart exactly which chemicals in the spit do what, a few of them seem to function as numbing agents to keep you from seeing youve been bitten.
Others appear to serve as anticoagulants and vasodilators, keeping your capillary open and your blood from clotting.
Now, there are over 100 proteins in mosquito saliva and not all of their functions are even understood yet.
We do know that mixed drink of chemicals is likewise why we get scratchy. So your body actually has an allergic response to mosquito bites, particularly to a few of those 100 chemicals in the mosquitos spit.
Your body immune system recognizes the foreign mosquito proteins and starts up a histamine action. This brings white blood cells to the area and it likewise activates other immune tools that cause irritation.
And I dislike all of it so much. They constantly discover me and I always get itchy and often those bites last for weeks.
How do they discover me in the very first place?
Mosquitoes use a lot of different sensory ideas to discover us. They can focus on our body heat. They can follow the aroma of CO2 from our breath. And I guess also just see us in some cases cause were truly huge and the mosquitoes are actually little so they can see us.
But those huge, broad sensory clues offer mosquitoes a concept about where humansare in basic. Once they discover our barbecue, how do they select who to chew down on?
Well, theres another huge manner in which mosquitoes discover us. Its skin smell.
There have actually been great deals of studies for many years to determine what makes some individuals smell a lot more delicious to some mosquitoes than others.
Some research studies have actually stated that blood type is included. Others suggest that what food or drink youve taken in might play a role. Some say that pregnancy may affect mosquito attractiveness.
And after that there are other research studies that state that the existence or absence of a malaria infection might affect whether or not mosquitoes wan na bite you.
So these research studies recommend that individuals contaminated with malaria may smell more appealing to mosquitoes than others, which is interesting since that would make it simpler for the malaria parasite to be circulated.
However different studies have actually all shown various magnitudes of effects and a few of them have actually revealed conflicting results.
It has actually been puzzling up until now.
In the past year, some of the coolest studies Ive ever seen on mosquito destination have been released and they have made me feel so vindicated.
The first was released in the fall of 2022. It took a look at fatty acids on our skin, particularly carboxylic acids that we exude in our sebum, a waxy, oily compound that helps keep our skin hydrated.
And this research study was incredible. The scientists had individuals wear fashion-forward nylon stockings on their arms to collect their sebum, and then established a chamber where Aedes aegypti mosquitoes might select between in a different way aromatic nylons.
And the option was strong.
Those of us who are mosquito magnets, we actually genuinely are magnetic to mosquitoes since they chose our scent method more than others.
Science for the win. Give me that peer-reviewed mosquito research study all day.
The research study took a look at the distinctions in the compounds between weak and strong attractors and they found that there were several various carboxylic acids that appeared more on the skin of the strong attractors than the weak attractors.
Particularly, the strong attractors produced considerably higher levels of three carboxylic acids, pentadecanoic, heptadecanoic, and nonadecanoic acids. They also discovered 10 other unidentified compounds in the very same chemical class.
And likewise, because this study was done over the course of 3 years, they were able to reveal that it wasnt something variable like what food the participants had consumed or whether they d had a beer just recently. These were steady attractants.
So why are they different in between people?
Could be a variety of things. We each may be genetically predisposed to produce slightly different skin compounds and the differences in our skin microbiomes might likewise influence the fatty acids that are present.
And as a geneticist, you understand that I am waiting on the follow-up studies on this.
I didnt need to wait long because in May of 2023, there was another mosquito magnet research study released from a various group. It once again looked at what made some people more attractive to mosquitoes than others.
This research study looked at Anopheles gambiae, another common mosquito types. And they utilized a fancy cam setup that enjoyed as mosquitoes arrived at warm body temperature level targets laced with different smells consisting of isolated attractants like CO2 and whole body smell from six different human beings.
And the setup for this was remarkable since they put the mosquitoes in a huge caged outdoor arena and then had little pipes leading away from that arena. At the end of each of the pipelines were tents which contained the targets and the various individuals. And they had fans that helped push the human aromas through the pipes into the main arena so that the mosquitoes could select where they wished to fly to.
They put a fan beside a sleeping human and after that attracted mosquitoes to them. Just genuinely wonderful.
As soon as again discovered that carboxylic acids were big distinguishing factors in between attractive and non-attractive human aromas, they. But this time, they found butyric, isobutyric, and isovaleric acids leading the pack for many appealing.
Now, they did likewise discover an intriguing observation that the least preferred human topic had a high abundance of eucalyptol in their body aroma. And yes, that sounds like eucalyptus because it is the main element of eucalyptus oil.
Assuming the individual isnt part tree, the compound likely originated from plant-based foods and flavorings in their diet. Now, this is just a single person. This is simply a hypothesis-generating observation rather than a big sweeping statement.
Could eucalyptol in diets help keep mosquitoes away? Perhaps, its a cool hypothesis.
Which leads me to my last point, which is how we, the magnets, can try and protect ourselves.
You might understand that DEET is a huge mosquito deterrent. And essentially, it is super smelly to the mosquitoes and makes it harder for them to smell us.
What about repellents obtained from nature? Things like citronella candle lights that everybody has on their porch in the summer.
Do they work? No? A 2017 research study found that citronella aroma mosquito repellents truly made no distinction in keeping mosquitoes away. What did work is oil of lemon eucalyptus.no difference in keeping mosquitoes away. What did work is oil of lemon eucalyptus.Thats lovely cool and makes good sense with what we were just saying. Even if its approach of action isnt rather clear, eucalyptus, child, its the response.
Lets attempt this out with our own homemade mosquito traps filled with dry ice to give off CO2. The CO2 and our breath is one of the biggest attractants to mosquitoes generally because keep in mind.
Im gon na assembled four mosquito traps, one with simply dry ice, one with DEET and dry ice, one with citronella and dry ice, and one with oil of lemon eucalyptus and solidified carbon dioxide.
Im gon na leave these out over night scattered around the yard, and then count the number of mosquitoes I catch in each one the next day.
So I failed. I stopped working so difficult at catching a single mosquito in Southern California.
So many mosquitoes flocked to me and I couldnt capture one. This is the one time in my life when I wanted a mosquito to come near me and like nothing, I got nothing.
I have actually failed you, ACS Reactions fans, and Im sorry. Andrew and George are in DC where there are tons of mosquitoes. I decided to send them to Rock Creek Park and see if they might evaluate the efficiency of different repellents.
I dont believe their heart was in it. I also absolutely do not have IRB approval for human experiments.
My job is weird.
Some individuals are more appealing to mosquitos than others, and new research study is starting to show why. There is actually something that makes us more attractive to mosquitoes, at least.
Mosquitoes use a bunch of different sensory clues to discover us. And I guess likewise just see us in some cases cause were actually big and the mosquitoes are actually little so they can see us.
A 2017 study discovered that citronella scent mosquito repellents truly made no difference in keeping mosquitoes away.