Mosquitoes (or midges, as they are sometimes known) are small, long-legged flying insects. There are over 3,200 known species worldwide, all with a similar life cycle: egg, larva, nymph (or pupa) and adult. Females lay their eggs (up to 300 eggs at a time) anywhere that has been standing water for at least a week. There the larvae hatch and grow.
Some species of mosquitoes live for just seven days, while others can live for up to a month. But let's get to the point: what attracts mosquitoes? What should we do when we get bitten? And, most importantly, why do mosquitoes only bite some people?
What attracts mosquitoes?
Mosquitoes feed by sucking liquids such as nectar, sap or, in the case of female mosquitoes, blood. Females do not need blood to survive, but they do need supplemental substances such as protein and iron to be able to lay eggs. So mosquitoes seek out animals and humans that they can bite to extract the substances they need. But how do they find them?
Mosquitoes are attracted to the carbon dioxide (CO2) we exhale with each breath, which explains why we feel them hovering near our faces and ears. Not only do mosquitoes seek out carbon dioxide, they also have receptors that help them recognize temperature, sweat and body odor to find food.
Why do mosquitoes only bite some people?
There are several reasons why mosquitoes choose some people and not others.
1. Carbon dioxide attracts mosquitoes.
The more carbon dioxide we exhale when we breathe, the more attractive we are to mosquitoes. In this sense, adults are more likely to be bitten, as are pregnant women.
2. Mosquitoes prefer blood type O.
This argument is not fully proven by the scientific community, but some studies seem to indicate that blood type O is more attractive to mosquitoes than all others. This would help explain why mosquitoes bite some people and not others, and although it is not scientifically proven, there is a lot of research being done on the relationship between blood type and mosquito bites.
3. Mosquitoes seek out our perspiration and lactic acid production.
The production of lactic acid is a natural consequence of metabolism during intense exercise. In simple terms, lactic acid is a way for our body to process glucose during high-intensity exercise and is released in sweat. Both body odor and lactic acid are elements that attract mosquitoes, so someone who does more physical activity or sweats more will be more likely to be bitten by mosquitoes.
4. Mosquitoes and midges prefer dark colors.
Mosquitoes are attracted to dark colors, which means the clothing we wear makes a difference in how likely we are to be bitten.
What to do in case of a mosquito bite?
In most cases, especially in Portugal where there are not many dangerous mosquito species, mosquito bites cause local irritation with redness, swelling, itching, increased temperature and, sometimes, pain. However, they are easily treatable at home. It is important to wash a mosquito bite with cold water and avoid scratching the irritated area. The cold will help reduce swelling and relieve the itching sensation, but you can also apply ice to speed up the process. Then, apply a soothing ointment or lotion to relieve the allergy to the bite.
How to avoid insect bites?
As we have seen, mosquitoes and midges prefer to bite certain people based on a set of criteria that are difficult to control. However, there are some measures that can be taken to avoid being bitten.
- Use insect repellents or mosquito repellents
- Avoid being outdoors at dusk and dawn, when mosquitoes are most active.
- Close doors and windows at night
- Avoid over-watering your garden and plants to prevent flooding
- If you have a swimming pool, clean it frequently and use the recommended amount of chlorine.
- Removes water from gutters after heavy rains
- Keep food and drinks closed or covered
- Cover your body with clothing that protects your arms and legs
Sometimes, especially in summer, we notice an invasion of mosquitoes that becomes difficult to control even with repellent. Find out what to do when you have a mosquito infestation.
