If you or someone you know seems to get bitten by mosquitoes more than others, there may be a scientific explanation. Some research suggests this happens because mosquitoes are more drawn to certain people based on blood type, body odor, and genetics.
The idea that mosquitoes prefer a certain blood type is controversial, and the results of studies have been mixed. For instance, an older study and a 2019 study found that mosquitoes tend to prefer people with type O blood and disfavor people with type A blood. However, a 2022 study found that mosquitoes preferred type B blood types.
Mosquitoes in the 2019 study were given the chance to feed on A, B, AB, and O blood types. Researchers found that these insects consistently chose type O blood more than any of the others.
However, the scientists noted that these results don’t mean that mosquitoes won’t bite people with other blood types. The preference for type O blood was only statistically significant when compared with blood type A. There was minimal difference in preference when comparing type O and the other blood types.
Some scientists argue that it is not just blood type that causes mosquitoes to be attracted to people. Skin odors, genetics, and microbiota (various bacteria, fungi, and other microorganisms) on the skin also may play a role.
Your DNA, or genetics, may contribute to your mosquito attraction. Researchers found that mosquito attraction may be an inherited trait similar to that of height or IQ. So, if one of your parents gets bitten by mosquitoes more often, you might too.
Researchers have also found that people with higher levels of the compounds called carboxylic acids on their skin were more attractive to mosquitoes. This trait remains stable for years, meaning your attractiveness to mosquitoes may not change much over time.
In addition to blood type, there are other ways that mosquitoes identify their targets. Attraction factors can range from body temperature and the amount of carbon monoxide you exhale to body odor, clothing color, and how much alcohol you drink.
Here are some ways mosquitoes pick who to bite:
- Body temperature: People with a higher body temperature may be more likely to attract mosquitoes. Researchers are still exploring this exact mechanism to potentially help repel mosquitoes and prevent bites.
- Skin bacteria: Researchers have found that the bacteria on your skin may be attractive to mosquitoes, especially if you have a lot of microbiota. Some experts suggest this may be why mosquitoes often target your feet and ankles, as the bacteria in these areas may be more appealing to mosquitoes.
- Sweat: Certain compounds in your sweat, like lactic acid and amino acids, may make you more attractive to mosquitoes, especially if it is mixed just right. To mosquitoes, this may make you taste better, though researchers are not exactly sure why.
- Alcohol consumption: One older study found that people who drink beer may end up with more mosquito bites than those who abstain from drinking. Researchers are unsure of the exact cause for this attraction, though.
- Clothing color: Mosquitoes also use vision to decide who to bite. They tend to be more attracted to colors like cyan (blue-green), red, orange, and black. Lighter, low-contrast colors like white and green are less preferred. So, wearing lighter colors may help you stay slightly less visible to mosquitoes.
- Pregnancy: Multiple studies have found that pregnant people attract about twice as many mosquitoes as non-pregnant women. This could occur because pregnant people have a higher body temperature and breathe out more carbon dioxide.
The World Health Organization (WHO) estimates that diseases spread by vectors—which include mosquitoes, fleas, ticks, and more—are linked to more than 700,000 deaths each year. This is largely due to the viruses and diseases these organisms carry, such as the Zika virus, West Nile virus, yellow fever, malaria, dengue, and more.
For this reason, it is important to take preventive measures to limit the number of mosquito bites you get. Here are some ways to prevent mosquitoes from biting you:
- Choose an EPA-registered insect repellent that has DEET, picaridin, IR3535, oil of lemon eucalyptus, or para-menthane-diol.
- Wear long sleeves, long pants, and socks when outside.
- Tuck your shirt into your pants and your pants into your socks to keep mosquitoes out.
- Mosquito-proof your home and use air conditioning or fans.
- Remove standing water from your flowerpots, gutters, pool covers, pet dishes, or birdbaths.
- Keep your swimming pool treated and the water circulating.
- Cover gaps in your walls, doors, and windows to prevent mosquitoes from entering.
- Talk to a healthcare provider if you plan to travel abroad to see if you need a preventative medication.
Some research suggests that mosquitoes choose their targets based on their blood type, with type O blood being the most popular and type A being the least desired. Other factors may also contribute to your mosquito attractiveness, like your genetics and skin odor.
Mosquitoes can carry several life-threatening diseases, so it’s important to prevent mosquito bites as much as possible. Choosing an EPA-approved insect repellent, wearing long sleeves and pants, and taking steps to reduce mosquitoes in your environment can help prevent bites.
