Aedes aegypti Mosquito: Identification, Bites, Range, and Disease
Short answer: Aedes aegypti, the yellow fever mosquito, is a small black mosquito with white markings that prefers to live near people and bite people. CDC guidance says infected Aedes mosquitoes spread dengue, Zika, and chikungunya viruses, and that Aedes species can bite during the day and at night. Container control matters because this mosquito breeds near homes.
What is Aedes aegypti also called?
Aedes aegypti is the yellow fever mosquito. According to an etymology in the CDC journal Emerging Infectious Diseases, the US Army Yellow Fever Commission's work showing that Aedes aegypti, also known as the yellow fever mosquito, was the principal vector remains one of the cornerstones of medical virology and tropical medicine. The same article explains the scientific name: Aedes is Greek for "unpleasant," and the journal calls Aedes aegypti the principal vector of several human diseases, including chikungunya, dengue, yellow fever, and Zika. The species name dates to 1757, when Fredrik Hasselqvist, a protégé of Carl Linnaeus, first described a mosquito collected in Egypt as Culex aegypti. Aedes albopictus, the other species in this article, goes by Asian tiger mosquito, the common name both the CDC and the California Department of Public Health use.
What does Aedes aegypti look like, and where does it live?
Aedes aegypti is one of two invasive (non-native) Aedes species the California Department of Public Health tracks closely. The California Department of Public Health (CDPH) names them Aedes aegypti, the yellow fever mosquito, and Aedes albopictus, the Asian tiger mosquito. Per CDPH, both are small, black mosquitoes with white stripes on the back and legs.
CDPH notes these mosquitoes live only near people and will lay eggs in any small water-holding container, indoors and outdoors. The CDC's dengue transmission page says the same thing from the mosquito's point of view: these mosquitoes prefer to bite people, and live both indoors and outdoors near people. The CDC draws one distinction between the two species: Aedes aegypti lives both indoors and outdoors, while Aedes albopictus lives outdoors.
Per the CDC, some mosquitoes like living near people while others prefer forests, marshes, or tall grasses; all of them like water, because mosquito larvae and pupae live in water with little or no flow. Aedes aegypti picked people.
It also stays put. Per the CDC, Aedes aegypti does not fly long distances; in its lifetime it will only fly a few blocks.
How do you identify an Aedes mosquito?
Start with the CDC's distinguishing features for Aedes aegypti: a dark brown body, white bands on the legs, white spots on the body, and stripes on the upper body that look like a lyre. The lyre is the mark to learn. The European Centre for Disease Prevention and Control (ECDC) calls it the prevailing diagnostic character: silver scales in the shape of a lyre against a black background on the scutum, the dorsal part of the thorax. In plain terms, look at the top of its back.
ECDC describes the adult as relatively small, with a black and white pattern made by white and silver scale patches on the legs and body. That contrast is the tell. ECDC notes that some native mosquitoes also show light and dark contrasts, more brownish and yellowish, but that these are less obvious.
- Dark body: dark brown per the CDC, with white and silver scales against a black background per ECDC.
- White bands on the legs.
- White spots on the body.
- Lyre-shaped stripes on the upper body: silver scales on the scutum, per ECDC.
In the CDC's description, the Asian tiger mosquito, Aedes albopictus, shares the white leg bands and body spots, which is why the lyre matters; the table further down compares the two. For the other biting insects worth recognizing, see the almanac.
When do Aedes aegypti mosquitoes bite?
The major health agencies phrase the biting window differently, and both phrasings are worth knowing. The CDC states that Aedes species mosquitoes "can bite during the day and night." The World Health Organization's dengue fact sheet puts it this way: "The mosquitoes that spread dengue are active during the day."
The WHO's Zika fact sheet adds detail: Aedes mosquitoes usually bite during the day and mostly outdoors, though they can also feed indoors. Its chikungunya fact sheet agrees, noting that both species bite primarily during daylight hours and that Aedes aegypti feeds both indoors and outdoors. Dusk-only precautions miss this mosquito's main shift.
And per the CDC, only female Aedes mosquitoes bite.
What diseases can Aedes aegypti spread?
Per CDPH, Aedes aegypti and Aedes albopictus can transmit dengue, chikungunya, and Zika viruses to people when they bite. The CDC describes dengue, Zika, and chikungunya viruses as typically transmitted directly between humans by Aedes aegypti, which can produce explosive epidemics.
Dengue. The WHO identifies Aedes aegypti as the primary mosquito that transmits dengue virus to humans. Per the WHO, about half the world's population is at risk of dengue, with an estimated 100 to 400 million infections each year. Most dengue infections cause no symptoms; when symptoms do appear, the most common are high fever, headache, body aches, nausea, and rash.
Chikungunya. Per the WHO, chikungunya virus is transmitted most commonly by Aedes aegypti and Aedes albopictus. It causes fever and severe joint pain that is often debilitating and may be prolonged.
Zika. The WHO reports that Zika virus is primarily transmitted by Aedes mosquitoes, mainly Aedes aegypti. Zika virus infection during pregnancy is a cause of microcephaly and other congenital malformations in the infant.
Yellow fever. The disease behind the common name. Per the WHO, yellow fever is vaccine-preventable and is caused by a virus transmitted by infected Aedes, Haemagogus, and Sabethes mosquitoes. Health authorities track Aedes aegypti specifically to assess the risk of urban yellow fever outbreaks.
If you develop symptoms like these after mosquito bites or travel, talk to a clinician. Headed somewhere these viruses circulate? Our dengue travel guide covers before, during, and after the trip.
Do all Aedes mosquitoes carry dengue?
The CDC names two: Aedes aegypti and Aedes albopictus. The CDC says mosquitoes become infected with dengue virus when they bite an infected person, and that infected mosquitoes can then spread it to other people through bites; the virus comes from a person first.
Per the CDC, over 200 types of mosquitoes live in the continental United States and US territories, and about 12 types spread germs that can make people sick. Dengue's mosquitoes are a narrow set: the CDC says dengue viruses are spread through the bites of infected Aedes species mosquitoes, Aedes aegypti or Aedes albopictus. Our West Nile virus guide covers a different virus.
How is Aedes aegypti different from the Asian tiger mosquito?
The two species look alike; per CDPH, both are small and black with white stripes. The differences that matter are behavioral. The CDC states that Aedes aegypti is more likely than Aedes albopictus to spread viruses like dengue, chikungunya, and Zika, and explains why: because Aedes aegypti lives near and prefers to feed on people, it is more likely to spread these viruses than other mosquitoes.
| Aedes aegypti | Aedes albopictus | |
|---|---|---|
| Host preference | Prefers to live near people and to bite people (CDC) | Bites people and animals, so it can live in or near homes or in neighboring woods (CDC) |
| Likelihood of spreading viruses | More likely than Aedes albopictus to spread viruses like dengue, chikungunya, and Zika (CDC) | Less likely than Aedes aegypti, per the same CDC comparison |
| Climate and temperature range | Lives in tropical, subtropical, and some temperate climates (CDC) | Can live in a broader temperature range and at cooler temperatures than Aedes aegypti (CDC) |
The climate rows draw on the CDC's potential-range materials, and the caveat the CDC attaches to its range maps applies here too: "Maps do not represent risk for spread of disease." For the full profile of the other species, see our Asian tiger mosquito guide.
Aedes aegypti vs Aedes albopictus: how do you tell them apart?
Both species are dark mosquitoes with white bands on the legs and white spots on the body, so the deciding mark is the lyre. The CDC's description of Aedes aegypti, the yellow fever mosquito, includes stripes on the upper body that look like a lyre; its description of Aedes albopictus, the Asian tiger mosquito, lists a black body, white leg bands, and white body spots, with no lyre among them. Beyond looks, the two differ in where they live; the table above covers what they bite, how much cold they tolerate, and, per the CDC, how likely they are to spread dengue, Zika, and chikungunya.
| Feature | Aedes aegypti | Aedes albopictus |
|---|---|---|
| Common name | Yellow fever mosquito (CDPH) | Asian tiger mosquito (CDPH, CDC) |
| Leg markings | White bands on the legs (CDC) | White bands on the legs (CDC) |
| Marking on the upper body | White spots on the body, plus stripes on the upper body that look like a lyre (CDC) | White spots on the body; the CDC's description lists no lyre |
| Where it lives | Indoors and outdoors (CDC) | Outdoors (CDC) |
Every row is species against species, drawn from the CDC and the California Department of Public Health.
Where in the United States is Aedes aegypti found?
The CDC reported in 2018 that Aedes aegypti's range has been expanding and that the species might be present in up to 38 states, though local transmission of the viruses it carries has been rare. A 2025 CDC report states that Aedes aegypti and Aedes albopictus are present in many counties in both the eastern and western United States and pose an ongoing risk for dengue transmission in new areas. Per the CDC, about half of US counties have competent mosquito vectors, and the climate in three quarters of the United States is suitable for Aedes species mosquitoes.
The CDC publishes maps showing its best estimate of the potential range of Aedes aegypti and Aedes albopictus in the contiguous United States. The maps include areas where the mosquitoes are or have been found, and the underlying model predicts the likelihood that these mosquitoes could survive and reproduce if introduced to an area. The CDC is explicit about what the maps are not: "Maps do not represent risk for spread of disease."
Mosquito presence and disease spread differ because an outbreak requires a chain: an infected person, a mosquito bite during the first week of infection, a mosquito that survives long enough to bite again, and repeated cycles, per the CDC. Most dengue cases reported in the continental US occur in travelers infected elsewhere; local transmission occurs occasionally. Limited local spread of dengue has been reported in Florida, Hawaii, Texas, Arizona, and California, and nearly every year, travelers have been associated with local spread of dengue in southern US states. The CDC assesses the risk of widespread dengue transmission in the continental United States as low.
The trend still deserves attention: per the CDC, dengue cases reported in US states and DC in 2024 hit a record, 359 percent above the 2010 to 2023 annual average. Where you live shapes when this matters; see mosquito season by region for timing.
Where are Aedes aegypti mosquitoes found around the world?
The CDC lists Aedes aegypti in southern and southwestern US states, Puerto Rico, tropical and subtropical areas of the world, countries in Africa and Asia, and parts of southern Europe, and describes it as living in tropical, subtropical, and some temperate climates. The European Centre for Disease Prevention and Control (ECDC) adds the origin: the species comes from Africa and is currently distributed throughout the tropics and a number of subtropical regions.
Europe is the edge of its range. ECDC says Aedes aegypti was historically present in Europe and that its current distribution there is limited but extending. Winter is what holds it back. ECDC attributes its restricted ability to establish itself in more temperate regions to its intolerance of temperate winters and, in particular, the high mortality rate of its eggs when exposed to frost.
Wherever it does establish, it stays close to people. ECDC says Aedes aegypti prefers human habitations because they provide resting and host-seeking possibilities. The county-level detail for the United States sits in the section above.
Why is Aedes aegypti so hard to control?
Start with the eggs. Per the CDC, female Aedes mosquitoes lay eggs on the inner walls of water-holding containers, above the waterline. The eggs stick to container walls like glue and can survive drying out for up to 8 months. Emptying a container does not finish the job, which is why the CDC's weekly advice says scrub, not just dump.
These mosquitoes need only a small amount of water to lay eggs; per the CDC, bowls, cups, fountains, tires, barrels, and vases all work. An egg takes 7 to 10 days to develop into an adult mosquito. A 2015 article in Emerging Infectious Diseases summed up the problem: these mosquitoes are daytime biters, need only small water containers to reproduce, and are difficult to eradicate.
At the public health level, the CDC describes the tools for vector control as limited, though they can be effective when implemented rapidly. The WHO states that prevention and control of dengue rely on vector control. At home, the CDC recommends that once a week you empty and scrub, turn over, cover, or throw out items that hold water. Our guide to standing water mosquito control walks through the routine.
How do you protect yourself from Aedes aegypti bites?
The CDC advises using EPA-registered insect repellents and looking for an EPA registration number on the repellent label, including for pregnant and breastfeeding women. Picaridin is one of the repellent active ingredients on the CDC's list; it is known as KBR 3023 and icaridin outside the United States.
Beyond repellent, the CDC advises wearing loose-fitting, long-sleeved shirts and pants, wearing clothing and gear treated with permethrin, using screens on windows and doors, repairing holes in screens, and using air conditioning if available.
One traveler-specific note: CDPH advises travelers returning to California from areas with these viruses to use mosquito repellent for at least three weeks after returning home, to prevent the spread of these viruses in California.
Where does Longsleeve fit? Longsleeve is an EPA-registered picaridin lotion (EPA Reg. No. 101457-1). It repels mosquitoes and ticks for up to 14 hours. It is fragrance free, with nine disclosed ingredients.
Frequently asked questions
Do Aedes aegypti mosquitoes bite at night?
The CDC states that Aedes species mosquitoes "can bite during the day and night." The WHO notes that the mosquitoes that spread dengue are "active during the day," and that Aedes mosquitoes usually bite during the day and mostly outdoors, though they can also feed indoors.
How far can Aedes aegypti fly?
Not far. Per the CDC, Aedes aegypti does not fly long distances; in its lifetime it will only fly a few blocks.
Do all Aedes aegypti mosquitoes bite?
No. Per the CDC, only female Aedes mosquitoes bite.
How long can Aedes aegypti eggs survive without water?
Per the CDC, the eggs stick to container walls like glue and can survive drying out for up to 8 months.
Is dengue spreading in the continental United States?
Per the CDC, most dengue cases reported in the continental US occur in travelers infected elsewhere, and local transmission occurs occasionally. Limited local spread has been reported in Florida, Hawaii, Texas, Arizona, and California. The CDC assesses the risk of widespread transmission in the continental United States as low.
More Longsleeve in your Google feed:
How do you tell an Aedes mosquito from an ordinary house mosquito?
Look at the contrast. ECDC describes Aedes aegypti as relatively small, with a black and white pattern made by white and silver scale patches on the legs and body. Some native mosquitoes show light and dark contrasts too, ECDC notes, but more brownish and yellowish and less obvious. The CDC's field marks for Aedes aegypti are white leg bands, white body spots, and lyre-shaped stripes on the upper body.
Can Aedes albopictus spread the same viruses as Aedes aegypti?
Yes. The CDC names Aedes aegypti and Aedes albopictus as the mosquitoes that spread dengue, Zika, and chikungunya viruses, and rates Aedes albopictus as less likely to spread them. The CDC says Aedes aegypti is more likely than Aedes albopictus to spread viruses like dengue, chikungunya, and Zika, because it lives near and prefers to feed on people. Aedes albopictus feeds on animals as well as people, which the CDC says makes it less likely to spread these and other viruses.
Sources
- California Department of Public Health, Aedes aegypti and Aedes albopictus Mosquitoes: https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/Aedes-aegypti-and-Aedes-albopictus-mosquitoes.aspx
- CDC, Life Cycle of Aedes Mosquitoes: https://www.cdc.gov/mosquitoes/about/life-cycle-of-aedes-mosquitoes.html
- CDC, Dengue Transmission: https://www.cdc.gov/dengue/transmission/index.html
- CDC, Potential Range of Aedes Mosquitoes: https://www.cdc.gov/mosquitoes/php/toolkit/potential-range-of-aedes.html
- CDC, Preventing Mosquito Bites: https://www.cdc.gov/mosquitoes/prevention/index.html
- CDC, Dengue Facts and Stats: https://www.cdc.gov/dengue/data-research/facts-stats/index.html
- CDC MMWR, Vital Signs: Trends in Reported Vectorborne Disease Cases (2018): https://www.cdc.gov/mmwr/volumes/67/wr/mm6717e1.htm
- CDC MMWR, Dengue Cases in US States and Territories (2025): https://www.cdc.gov/mmwr/volumes/75/wr/mm7518a1.htm
- CDC Emerging Infectious Diseases (2015): https://wwwnc.cdc.gov/eid/article/21/10/15-0494_article
- CDC, About Vector-Borne Diseases: https://www.cdc.gov/vector-borne-diseases/about/index.html
- CDC, Where Mosquitoes Live: https://www.cdc.gov/mosquitoes/about/where-mosquitoes-live_1.html
- WHO, Dengue and Severe Dengue: https://www.who.int/news-room/fact-sheets/detail/dengue-and-severe-dengue
- WHO, Chikungunya: https://www.who.int/news-room/fact-sheets/detail/chikungunya
- WHO, Zika Virus: https://www.who.int/news-room/fact-sheets/detail/zika-virus
- WHO, Yellow Fever: https://www.who.int/news-room/fact-sheets/detail/yellow-fever
- CDC, Unwanted Mosquitoes (Dengue). https://www.cdc.gov/dengue/stories/unwanted-mosquitoes.html
- European Centre for Disease Prevention and Control, Aedes aegypti: Factsheet for experts. https://www.ecdc.europa.eu/en/disease-vectors/facts/mosquito-factsheets/aedes-aegypti
- CDC Emerging Infectious Diseases, Etymologia: Aedes aegypti (2016). https://wwwnc.cdc.gov/eid/article/22/10/ET-2210_article
- CDC, About Mosquitoes in the United States. https://www.cdc.gov/mosquitoes/about/about-mosquitoes-in-the-united-states.html
Last reviewed 2026-08-16 · every claim on this page is sourced above