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Be careful

Yellow fever mosquito

Aedes aegypti
Also called Aedes aegypti

Most bites only itch, but this daytime-biting mosquito is the main US carrier of dengue, Zika and chikungunya, which have spread locally in a few southern states.

If you get a fever, rash, headache or joint pain after mosquito bites, see a doctor and mention the bites and any travel.
Yellow fever mosquito, photo 1
Photo: Dan Mendelowitz, CC BY 4.0, via iNaturalist
SizeAbout 4–7 mm (roughly 1/4 inch) long.
Where in the houseBedroom, living room, bathroom, kitchen, outside near the house
WhenWarm months. CDC puts US mosquito season at roughly June through October; in the warmest southern areas it can run longer.

Check these features

  1. Small, dark brown to black mosquito with bright white markings
  2. White scales on top of the thorax forming a lyre or violin shape (two curved lines with a stripe between)
  3. White bands at the joints of the legs, giving a striped look
  4. Bites during the day, often around ankles, indoors as well as outdoors

Bites and stings

Bites usually cause an itchy bump that fades in a few days. Rarely, a bite can pass on dengue, Zika or chikungunya, mainly in parts of Florida, Texas, Arizona, California and Hawaii where local spread has occurred, or in US territories such as Puerto Rico. See a doctor for fever with headache, body or joint pain, or rash, especially after travel or during a local outbreak. Get emergency care for belly pain, repeated vomiting, bleeding from the nose or gums, or extreme tiredness after a fever; call 911 for trouble breathing or swelling of the face or throat.

What to do

  1. Wash an itchy bite with soap and water and avoid scratching.
  2. If you get a fever, rash, headache or joint pain after being bitten in an area with local spread or after travel, see a doctor and mention the mosquito bites and travel.
  3. Empty, scrub, turn over or cover anything holding water around the house every week, including plant saucers, vases, pet bowls, buckets and tires; scrubbing removes eggs stuck to the sides.
  4. Repair window and door screens, keep doors closed, and use air conditioning when you can.

Look-alikes

Asian tiger mosquitoAlso black with white bands, but has a single white stripe down the middle of the thorax instead of a lyre shape.
Northern house mosquitoHouse mosquitoes are plain brown without bright white bands and mostly bite at dusk and at night.

Why it came inside

This mosquito lives close to people. It lays eggs just above the waterline in small containers such as flowerpot saucers, vases, buckets and tires, and adults readily come indoors through open doors and torn screens to bite.

Keep it out

  • Dump and scrub standing water at least weekly, indoors and out.
  • Cover rain barrels and water storage tightly or with fine mesh, and treat water that cannot be emptied with mosquito dunks, following the label.
  • Keep gutters clear and change birdbath water often.
  • Use an EPA-registered insect repellent and wear long sleeves and pants, especially during the day when this mosquito bites.

What helps

Links go to Amazon search results so you can compare current options. As an Amazon Associate I earn from qualifying purchases. Always follow the product label.

EPA-registered insect repellent

Look for an EPA-registered repellent with DEET, picaridin, IR3535 or oil of lemon eucalyptus, and follow the label, especially for children.

See options on Amazon
Screen repair kit

Patches or replaces torn window and door screens, one of the most common ways insects get in.

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Mosquito dunks (Bti)

Kill mosquito larvae in standing water you can't drain, like rain barrels and ponds. Follow the label.

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Door sweep

Closes the gap under an exterior door. If you can see daylight under the door, bugs can get in.

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Sources

  1. CDC
  2. CDC
  3. CDC
  4. University of Florida IFAS Extension
  5. CDC

Checked October 18, 2026. Rating backed by 4 sources. How we rate danger.