When I went to Brunei some years ago, I was determined not to take prescription medicine to prevent malaria. I decided to ward off malaria-bearing mosquitoes by taking garlic and vitamin B12 capsules for two weeks prior to departure. It worked like a dream, so on the following trip I used the same procedure and I did not get even one mosquito bite. But there is no scientific evidence that this actually works for everybody, so I cannot recommend it.
There are lots of theories about why mosquitoes attack some people, and not others. Larger persons who emit more C02, beer-drinkers, and sweatier people have all come under scrutiny. There is some evidence that these groups hold some attraction for mosquitoes, so we will have to look at possible reasons and try to find an answer.
We now know that genetics and the body chemistry are the keys to understanding this fatal attraction. Statistically, only about one in ten people are particularly attractive to mosquitoes. It may be of some comfort to know that the Dalai Lama is also one of their targets and that he is not so kindly disposed towards them!
“My attitude toward mosquitoes and bedbugs is not very favorable or peaceful! “
—Dalai Lama
Why do mosquitoes attack some people and not others?
Let us look at what mosquitoes are looking for when they crash land on our skin. No sexism here but only female mosquitoes will bite as they need mammal blood to feed their eggs. There are also 150 species in the USA alone and they all have preferences for their ideal blood fix. Some experiments use one mosquito species and then get different results when they repeat the experiment with an alternative one.
Mosquitoes are choosy and they want the best for their eggs. We produce chemicals and microbes which make up our unique body odor. They know exactly the right chemical mix and its odor because this accurately represents the blood they want. They can also detect these attractive aromas up to 100 feet away!
What makes up this chemical mix? Just think that we have 100 trillion microbes which is ten times the number of human cells we possess. We have a unique microbial signature which is mostly due to genetics. This will determine what type of bacteria we host in our gut and bodies. These microbes are an essential part of our immune system so washing frequently is not going to do any good. It will certainly not deter the mosquitoes zooming in because their sense of smell is extremely sharp.
Your blood type is another factor.
The mosquito is after blood and if it smells right, you are going to be a target. In one limited experiment, they found that mosquitoes preferred people with Type O blood twice as much as those with Type A. It is fascinating to know that in 85% of cases, you actually send a chemical signal indicating which blood type you have.
What makes a delicious cocktail for a mosquito?
More sweat and carbon dioxide have been cited but the results from experiments are not always consistent. This is due mainly to the many different species and the enormously complex odor making mechanisms each of us possesses.
Lactic acid seems to be a definite attraction to most mosquito species and there have been more research studies on this. When you eat certain foods such as cheese, soya, yogurt and pickled vegetables and do vigorous exercise, you will have more lactic acid on your skin. That is very attractive to some mosquito species.
Don’t believe all those people who say they are never bitten!
The fact is that many more people are bitten by mosquitoes than you would think. It is all due to the reaction as people react in different ways to the mosquito leaving saliva when sucking their blood. This depends on environmental and allergic reactions. Many more people are bitten but because they have no symptoms they are convinced that they are not attractive to mosquitoes. If only they knew!
To sum up, genetics and our chemical/microbial mix are really going to determine whether we are going to be bitten by mosquitoes or not. There seems to be a link between these and the blood type. The amount of CO2 , garlic or alcohol we consume or dark colored clothing are all secondary factors but may help in keeping these mosquitoes at bay.
Practical ways to keep mosquitoes away.
Taking a few simple precautions can help. Covering up most exposed parts of the skin is a definite advantage. You can make sure that you put herbs and plants in your garden or on your balcony which actually repel mosquitos. Avoid going out when humidity is at its peak at dawn and dusk. This is also the time when winds die down which give mosquitoes better landing conditions!
Featured photo credit: mosquito bite/dr-relling via flickr.com
