SCIENTISTS ARE NOW figuring out why mosquitoes are attracted to biting some people, and ignore others.

There are about 18 to 20 mosquito species which call Ireland home. The good news is they are not known to carry any human infections – although the impact of climate change may change this in Europe.

We are nearing peak season for the bloodsuckers, which can cause small, itchy bumps with swelling, as well as blisters in some people.

Scientists now think that rather than specific blood types, factors that attract mosquitoes include body odour and heat, which can be impacted by things like drinking beer.

Mosquito magnets

Frederic Simard of France’s Institute of Research for Development said it is “not a misconception” that mosquitoes are attracted to some people more than others.

A range of sensory cues can cause mosquitoes to pick one human over another – mainly the smell and heat our bodies give off, and the carbon dioxide we exhale.

Female mosquitoes – which are the only ones that bite – detect these signals with finely-tuned receptors, then choose their target accordingly. As they get closer, body temperature and humidity make particular humans even more enticing.

Odour in particular impacts who a mosquito bites, but scientists are only just beginning to understand which odours attract mosquitoes.

A recent study of 42 women found that the woman the mosquitoes most liked to bite – which included pregnant women in their second trimester – produced a large amount of a particular compound made by a breakdown of the skin oil sebum.

Drinking beer has also been linked to attracting mosquitoes, because it raises body temperature, increases the amount of exhaled CO2 and changes skin odour, according to several studies.

For a 2023 study in the Netherlands, 465 volunteers put their arms in cages filled with female Anopheles mosquitoes. The volunteers who had drunk beer in the previous 24 hours were 1.35 times more attractive to the mosquitoes.

The recommendations to avoid getting bitten? Try wearing loose-fitting clothing that covers your skin, and use mosquito nets and repellent.

Light meals and a low alcohol intake can also prevent mosquitoes being attracted to you.

Insect bite treatment

If you are bitten or stung by an insect, HSE advice suggests you remove any stingers, ticks or caterpillar hairs. If there’s nothing on or in your skin, or you’ve removed what was there, wash the affected area with soap and water.

If the insect bite or sting is not serious, you can put a cold compress on it and keep the area raised to reduce swelling. Medicines that can help ease the symptoms, include antihistamines, steroid creams and painkillers, such as ibuprofen or paracetamol.

The HSE said you should not scratch the bite or sting or burst any blisters, or use home remedies such as bicarbonate of soda and vinegar to treat it.

If the swelling at the bite or sting is severe, your GP may prescribe steroid tablets, and if you have an allergic reaction, your GP may prescribe an adrenaline pen of refer you to an allergy clinic.

If you have symptoms of a severe allergic reaction, including, wheezing or difficulty breathing, a swollen face, mouth, lips, tongue or throat or a skin rash, you should call 112 or 999 or go to your nearest emergency department.