
Mosquitos are annoying insects that can spread diseases. These biting and blood-sucking insects can also cause red bumps and skin irritation. There are some places with more mosquitos than others, including southern states. But where can you find the most mosquitos? How can you avoid being bitten? Follow along to discover the top 10 mosquito-infested US states.
1. Florida
The state with the most mosquitos is Florida. This beloved peninsula is warm and humid almost all year round, which is the perfect habitat for mosquitos. In Florida alone, there are at least 80 mosquito species, however, there are five you should know. According to the Florida Department of Health, the worst mosquitos in the state are the yellow fever mosquito, the Asian tiger mosquito, the southern house mosquito, the black salt marsh mosquito, and the gallinipper.
Some of these carry diseases, like the southern house mosquito, which carries the St. Louis encephalitis virus, and the West Nile virus. This mosquito is found in all Florida counties and is common near water. The number of marshes and water is likely why Florida is so mosquito-infested. To prevent mosquitos in your yard or home, always pour water out of containers. Mosquitos thrive in standing water.

Southern house mosquitos spread diseases like the West Nile virus.
©iStock.com/Arnav Ray
2. Texas
The next mosquito-infested US state on our list is Texas. Like Florida, Texas has a lot of standing water and marshes, which are mosquito habitats. Mosquitos are a lot worse during the summer when the weather is warmer and humidity increases. There are over 80 species of mosquitos living in Texas, but the four most common are yellow fever mosquitos, Asian tiger mosquitos, house mosquitos, and southern mosquitos.
Mosquitos are difficult to control in Texas. There is too much flooding, which attracts breeding mosquitos. Female mosquitos lay between 100 to 200 eggs. Mosquitos need as little as a teaspoon of water to breed. Some mosquitos in Texas can transmit diseases like chikungunya, dengue, and malaria.

Asian tiger mosquitos live in Texas, one of the most mosquito-infested US states.
©Sarah2/Shutterstock.com
3. Louisiana
Another southern mosquito-infested US state is Louisiana. This state is known for its swamps, like Florida, which are breeding grounds for mosquitos. While there aren’t as many mosquito species in Louisiana, you can still find 68! The most common mosquitos in Louisiana are the Asian tiger mosquito, southern house mosquito, woodland mosquito, dark rice field mosquito, malaria mosquito, and floodwater mosquito.
Dark rice field mosquitos are aggressive. The females are fierce biters, attacking during the day and at night. These are more common after a hurricane in flooded conditions. They carry the West Nile Virus and the Venezuelan Equine Encephalitis. After heavy rain and in the summer, it’s more common to see the inland floodwater mosquito. Their bites are painful and they are difficult to get rid of or prevent.

The dark rice field mosquito carries the West Nile Virus and delivers a powerful and painful bite.
©xpda / CC BY-SA 4.0 – License
4. Georgia
Next is Georgia, with about 63 known species. Thankfully, out of these 63 mosquito species, only about 10 to 12 are pests that spread diseases. The most commonly reported mosquito-spread disease in Georgia is the West Nile Virus. However, you can contract other diseases like La Crosse encephalitis and Saint Louis encephalitis virus. The best way to avoid getting sick is to prevent mosquito bites. This isn’t always possible, but there are a few things you can do.
Mosquitos are most active during sunrise and sunset in early spring through fall. Wear clothes that cover your arms and legs. You can also use a mosquito repellant, but some species are resilient.

To prevent mosquito bites, wear clothes that cover your skin.
©9nong/Shutterstock.com
5. North Carolina
North Carolina mosquitos are a nuisance. The mosquitos are mainly small and hard to notice, but deliver a painful and itchy bite that swells up. The most common mosquito-transmitted diseases in North Carolina are the West Nile Virus, eastern equine encephalitis (EEE), and La Crosse encephalitis (LAC).
North Carolina mosquitos are most active from March through October. They disappear as the weather cools down. The most common species in North Carolina is the northern house mosquito. As their name suggests, they live indoors and in yards. They are very active at night and are found in pools, birdbaths, and trash cans. However, on the eastern side of North Carolina, you can find the eastern salt marsh mosquito, which breeds in marshes along the coast.

Northern house mosquitos are the most common species in North Carolina.
©Anest/Shutterstock.com
6. Alabama
Alabama is a southern state near Georgia, North Carolina, and Florida, the states with the most mosquitos. That’s why it’s no surprise that Alabama makes our list of the top 10 mosquito-infested US states. In Alabama, there are about 60 different types of mosquitos, however, not all are dangerous or spread diseases. The mosquitos you should watch out for in Alabama include the yellow fever mosquito, Japanese encephalitis mosquito, Asian tiger mosquito, southern house mosquito, and eastern tree-hole mosquito.
Mosquitos don’t just spread diseases to humans. Some also carry heartworm which affects dogs. Although you can prevent mosquito bites using EPA-registered mosquito repellants, it doesn’t always work. You can also use natural mosquito repellants but always reapply. One of the best ways to prevent mosquitos in your yard is to dump out excess or standing water. Don’t overwater your plants either as moisture can attract mosquitos.

Yellow fever mosquitos are common in Alabama.
©Wirestock Creators/Shutterstock.com
7. South Dakota
While most mosquito-infested US states are in the south, there are exceptions like South Dakota. In South Dakota, you can find over 40 mosquito species. However, two species are more common, the inland floodwater mosquito and the western encephalitis mosquito. Both can spread diseases like the Western Nile Virus, however, the western encephalitis mosquito is more dangerous.
You can’t always avoid being bitten by a mosquito. However, if possible, avoid going outside in short sleeves during sunrise and sunset. Always cover your pool and mow your lawn as adult mosquitos live in tall grass.

Mosquitos are found throughout South Dakota.
©Krumpelman Photography/Shutterstock.com
8. Oklahoma
Oklahoma is next on our list, which isn’t surprising since it’s above Texas. In Oklahoma, there are at least 60 mosquito species, but the most troublesome are the yellow fever mosquito, inland floodwater mosquito, Asian tiger mosquito, common malaria mosquito, and common house mosquito.
The common malaria mosquitos are slender and long. These are common along lakes and ponds. They live in aquatic habitats and have four distinct dark marks on their wings. Common malaria mosquitos feed on humans and can wander inside. They transmit dog heartworm and malaria. To avoid letting mosquitos in your home, patch up any holes in your windows and doors.

Common malaria mosquitos transmit malaria and dog heartworms.
©https://pixnio.com/fauna-animals/insects-and-bugs/mosquito/close-up-photograph-of-an-anopheles-quadrimaculatus-mosquito-on-white-background# – License
9. Montana
It’s hard to escape from mosquitos in Montana. One study identified 50 distinct mosquito species by trapping 100,000 mosquitos. While there are many species, about 90% of the mosquito population in Montana are the inland floodwater mosquito and the western encephalitis mosquito. Both are powerful and aggressive biters, especially at night. In Montana, most mosquitos are out in spring and summer.

There are 50 recorded mosquito species in Montana.
©Paul W Thompson/Shutterstock.com
10. Virginia
Last but not least on our list of the most mosquito-infested US states is Virginia. Like Montana, there are at least 50 mosquito species. They live in aquatic environments and are common in residences near lakes or ponds. However, these pesky mosquitos can make their way into your home quickly, especially if water is left standing.
While mosquitos are found throughout the state, they are more common in northern Virginia. One of the most common species is the Asian tiger mosquito. Although it’s rare to contract a disease from a mosquito bite, if you notice a red bump, always wash it with cold water and soap. Try to ignore the itchiness as scratching can cause infections.

Always wash a mosquito bite with water and soap.
©DimaBerlin/Shutterstock.com
Summary of the 10 Most Mosquito-Infested US States
Rank | State | Mosquitos |
---|---|---|
1 | Florida | 80 species |
2 | Texas | Over 80 species |
3 | Louisiana | 68 species |
4 | Georgia | 63 species |
5 | North Carolina | 60 species |
6 | Alabama | 60 species |
7 | South Dakota | Over 40 species |
8 | Oklahoma | 60 species |
9 | Montana | 50 species |
10 | Virginia | 50 species |
The photo featured at the top of this post is © jiade/Shutterstock.com
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