What Are Mosquito-Borne Diseases?

Mosquito-borne diseases are illnesses spread by the bite of an infected mosquito. They include:

• chikungunya
• dengue fever
• Eastern and Western equine encephalitis
• Japanese encephalitis
• La Crosse encephalitis
• malaria
• St. Louis encephalitis
• West Nile virus
• yellow fever
• Zika virus

Viruses cause most diseases spread to people by mosquitoes. Malaria is caused by a parasite.

Different mosquitoes carry different diseases. How common these illnesses are depends on where people live or travel to, and the time of year.

What Are the Signs & Symptoms of Mosquito-Borne Diseases?

Signs and symptoms vary depending on the mosquito-borne disease. Most people don't get sick, or have only mild symptoms after being bitten by an infected mosquito.

Signs and symptoms may include:

• fever
• headache
• neck pain
• muscle pain
• joint pain
• rash
• vomiting
• diarrhea

Rarely, mosquito-borne diseases can cause serious problems, such as encephalitis, a swelling of the brain.

How Are Mosquito-Borne Diseases Treated?

Most mosquito-borne diseases do not have specific treatments. Someone with a mosquito-borne infection should get plenty of fluids and rest. Doctors will treat symptoms, such as fever or pain, and watch for any problems.

There are prevention medicines and specific treatments for malaria.

Can Mosquito-Borne Diseases Be Prevented?

The best protection against mosquito-borne diseases is to prevent bites by infected mosquitoes. Be sure to:

• Use screens on doors and windows, and repair broken or damaged screens right away. Keep unscreened doors and windows shut.
• Wear long-sleeved shirts, long pants, shoes, and socks outside, and use mosquito netting over beds.
• Use insect repellent as directed. Choose one with DEET or picaridin. For kids over 3 years old, you also can use oil of lemon eucalyptus.
• Limit time outside around dawn and dusk, when mosquitoes are most active.
• Don't give mosquitoes places to breed. They lay their eggs in water, so get rid of standing water in things like buckets, trash cans, and tires. Empty and clean birdbaths, dog bowls, and flowerpots at least once a week.

Vaccines can prevent some mosquito-borne illnesses, such as dengue fever, yellow fever, and Japanese encephalitis. Talk to your doctor if you live or travel to places where mosquito-borne diseases are found.