Why Do Mosquitoes Bite You?

Nature's mechanisms are surprising. Female mosquitoes depend upon blood from humans and certain other animals for nourishment. During feeding, they inject an anticoagulant, which causes an itching sensation. Meanwhile, male mosquitoes have a different physiological system and only feed on plant sap for sustenance.

Mosquitoes and Blood-Biting for Reproduction

Mosquitoes bite and suck blood for reproduction. While male mosquitoes survive on flower nectar, female mosquitoes consume both nectar and blood. The females need the protein from blood to develop their eggs.

Why Do Mosquitoes Prefer You?

Even though you are sound asleep, you are still fighting mosquitoes in the dark. There are more than 3,500 species of mosquitoes worldwide, and not all of them are a concern to humans. Female mosquitoes require blood to reproduce, but male mosquitoes are vegetarians, focusing on mating.

Even a mosquito that is more than ten meters away can find you based on the carbon dioxide you exhale. This mosquito's head houses carbon dioxide-sensing neurons that can detect fluctuations as low as 0.005% in carbon dioxide concentration and activate the visual system to head your way.

Women who are pregnant may attract mosquitoes more, as they exhale 21% more carbon dioxide than the average person. At around 1-2 meters away, mosquitoes can recognize your body outline. Large amounts of sweat and odor are also significant attractors. Sweat contains volatile compounds that attract mosquitoes. Even odorous substances left on socks can attract 66% of mosquitoes.

How Mosquitoes Find You

The mosquito's journey to your skin involves a series of sensory cues. Temperature, humidity, and temperature are key. Mosquitoes have the highest landing rates on surfaces close to human body temperature. Extreme temperatures (too hot or too cold) reduce their landings. The higher humidity around humans, due to sweat secretion, also helps mosquitoes determine that a target is a live person.

Once the mosquito is within arm's reach, it pierces the skin with its mouthparts, which consist of six parts. The lower jaw cuts through the flesh, and the upper jaw separates the tissue. The mosquito then draws blood into its body. During the process, the mosquito also spits saliva, which both anesthetizes the skin and prevents blood coagulation.

Facts About Blood Types and Mosquito Preferences

Though you may have heard that mosquitoes love to drink type O blood, studies have shown that the concept is a myth. A 1972 study suggested that people with type O blood were bitten more frequently, but a 2000 study found that mosquitoes showed no preference for any blood type. Therefore, you might as well use a repellent to keep mosquitoes at bay. Common repellent ingredients include DEET, IR3535, and plant essential oils. DEET can provide up to 5 hours of protection, while other repellents offer shorter durations.

Killing Mosquitoes with Insecticides

To eliminate mosquitoes, you may need to use insecticides, such as mosquito coils containing pyrethroids. These substances interfere with the mosquito's nervous system, causing them to over-excite and die within seconds. However, mosquitoes can evolve resistance to insecticides, as they have a longer lifespan than humans and have long understood the truth of resistance.

In conclusion, understanding why mosquitoes bite and their preferences can help you fight them more effectively. Whether it's avoiding carbon dioxide-emitting activities or using the right repellents, you can keep these pesky insects away from your next outdoor gathering or sleepover.