Mosquitoes exhibit a preference for certain individuals, a phenomenon attributed to a variety of biological and lifestyle factors. These insects rely on a combination of cues to locate their targets, making some people more attractive than others.
One significant factor is carbon dioxide (CO2) production. Mosquitoes are highly attracted to the CO2 exhaled by humans and animals. Individuals with higher metabolic rates, whether due to genetics, physical activity, or other physiological differences, produce more CO2, thereby increasing their attractiveness to mosquitoes.
Beyond CO2, mosquitoes utilize "secondary cues" to pinpoint hosts. Lactic acid, a byproduct of strenuous exercise that can cause muscle cramps, is one such cue. Released through the skin, lactic acid signals to mosquitoes that a person is a potential blood source. Body heat also plays a crucial role; mosquitoes are drawn to individuals whose body temperature is slightly higher, as this often indicates blood is closer to the skin's surface.
Clothing color can also influence mosquito attraction. Mosquitoes have good vision but fly close to the ground. They can contrast a person against the horizon, making dark-colored clothing more attractive because it stands out more than lighter colors.
Lifestyle and health conditions can further increase susceptibility. Factors such as drinking alcohol, being pregnant, or being overweight can elevate metabolic rates, making individuals more appealing to mosquitoes. One study indicated that consuming even a single can of beer can increase a person's risk of attracting mosquitoes.
While personal factors contribute to attractiveness, preventive measures can mitigate bites. Avoiding peak mosquito activity times, typically during sunrise and sunset, is recommended. Covering exposed skin with breathable, long-sleeved clothing and pants can offer physical protection. The use of insect repellents containing DEET is considered highly effective. Despite some public concerns, the Environmental Protection Agency has concluded that normal use of DEET products is safe for all age groups, including children and pregnant women.
Other methods to deter mosquitoes include using fans to create airflow, as mosquitoes struggle to fly in windy conditions. While natural repellents like citronella candles are often suggested, research has not yet supported their effectiveness. If bitten, scratching should be avoided as it can worsen itching and lead to infection. Applying ice or over-the-counter anti-itch creams with hydrocortisone can help alleviate discomfort. Antihistamines may also provide relief from itching and allergic reactions.