August 28, 2016

View as List How to Prevent Mosquito Bites

  • How to Prevent Mosquito Bites

    Avoid the swatting and itching—and the risk of mosquito-borne illnesses like Zika virus and West Nile virus—with this savvy survival guide.

  • 1

    Do all mosquitoes bite?

    No. Only female mosquitoes bite—that is, draw blood through a syringe-like appendage on their heads—because they need blood to nourish their developing eggs. Some mosquito species favor humans, while others prefer birds, cattle, or other animals. Some species are active mostly during early evening hours, some at night, and others during daylight hours. 

  • 2

    Why does the bite itch?

    When a female mosquito lands on your skin, she injects her saliva, which contains a protein that keeps your blood from coagulating (so it can be easily siphoned) and triggers an immune reaction and the release of histamine, resulting in an itchy red welt. 

  • 3

    Why do mosquitoes prefer certain people?

    It’s something about their biochemistry. Mosquitoes are attracted to the carbon dioxide we exhale, as well as other chemicals we secrete or exhale, the heat from our bodies, and certain bacteria on our skin. Some chemicals are more attractive to certain mosquito species than others; some compounds actually help conceal us from mosquitoes. We all produce the same chemicals, but in different proportions, making us more, or less, appealing.

  • 4

    What diseases do mosquitos spread?

    Different mosquito species host different viruses and parasites that can cause diseases in humans. In recent years West Nile virus made the most headlines as it spread in the US. But now the newsmaker is the Zika virus, which is in more than 60 countries and spreading rapidly. Worldwide, though, the big mosquito-borne diseases remain malaria, yellow fever, dengue fever, chikungunya, and inflammatory brain illnesses such as Japanese encephalitis. So far, most of these are rare in the US.

  • 5

    How can I avoid getting "bitten"?

    Wear long sleeves and pants that are light-colored and loose-fitting, as well as socks and closed-toe shoes. Most important, use an effective, long-lasting, EPA-registered insect repellent that contains DEET (preferably 20 to 30 percent), oil of lemon eucalyptus, picaridin (preferably 20 percent), or IR3535. You can also spray clothes (not skin) with permethrin, or wear permethrin-treated garments. (You still need to put repellent on exposed skin.)

  • 6

    Will any food or dietary supplement help repel mosquitoes?

    No, despite anecdotal reports. A 2015 paper in PLOS ONE concluded that consuming garlic, B vitamins, beer, and other commonly proposed aids do not help. And a study in the Journal of Insect Science in 2015 found that a vitamin B patch is ineffective.

  • 7

    How can you control mosquitoes in your yard?

    Mosquitoes lay their eggs in standing water, so remove (or empty) anything in your yard that can collect water, such as hollow logs, holes in trees, pool covers, old tires, and pet dishes. Clean out clogged rain gutters. Drill holes in the bottom of outside garbage con- tainers. Make sure screens on windows and doors fit tightly and have no holes.Try yellow “bug lights” on decks and porches; they attract fewer mosquitoes than regular lights.

  • 8

    Do zappers or ultrasonic devices help?

    According to several review articles, bug zappers and ultrasonic repellers do little, if anything, to control mosquitoes; they kill far more moths and flies. The latest twist: phone apps that emit ultrasonic wavelengths that are supposed to repel mosquitoes. Like older ultrasonic devices, there’s no evidence they work (online anecdotes don’t count as scientific evidence). Because mosquitoes are weak flyers, one good low-tech option is a powerful fan, preferably oscillating.

  • 9

    How can I treat an itchy "bite"?

    Apply ice, and try not to scratch. Ammonium solutions (in many after-bite products) provide some relief. Calamine lotion or hydrocortisone cream may also help. If you are sensitive to mosquitoes, taking antihistamines before you go out may lessen reactions to stings. An oral antihistamine can help with severe itching.