What is malaria?

Malaria is a disease that causes a fever and other flu-like symptoms, such as chills, headache, muscle aches, nausea, vomiting, and diarrhea. A severe type of malaria can cause serious heart, lung, kidney, and brain problems, or death.

You can get it from a bite from an infected mosquito. The infection is caused by a parasite and does not spread from person to person. Malaria is very rare in the United States. It's most often found in Africa, Southern Asia, Central America, and South America. Travel to these areas may increase your risk of getting it.

You can reduce the risk of getting malaria by taking steps to prevent mosquito bites and by taking preventive medicine that reduces the risk of infection in case you are bitten by an infected mosquito.

What causes it?

You get malaria when a mosquito infected with parasites bites you and transfers the parasite to you. You can't get malaria just by being near a person who has the disease.

What are the symptoms?

Most malaria infections cause flu-like symptoms that may come and go in cycles. These may include:

• Fever. This is the most common symptom.
• Chills.
• Headache.
• Sweats.
• Fatigue.
• Nausea and vomiting.
• Body aches.
• Generally feeling sick.

People who get infected many times may have the disease but have few or no symptoms. How bad malaria symptoms are can vary depending on your age, general health, and the type of malaria that you have.

A severe type of malaria can cause serious heart, lung, kidney, and brain problems, or death.

The time from when you get infected until symptoms appear is usually 7 to 30 days. But with some infections, symptoms may not appear for many months.

How is it diagnosed?

The doctor will ask you questions about your health and do a physical exam. If the doctor thinks you may have malaria, a sample of blood will be taken. It is prepared on a glass slide and looked at under a microscope.

A blood smear test can help diagnose malaria. It can also help a doctor see what type of malaria parasite you have and how many parasites are in your blood. This can help with decisions about treatment.

If the first blood smear doesn't show malaria, your doctor may order more tests every 12 to 24 hours.

A blood test that can diagnose malaria quickly is also available. If this rapid test points to malaria, the results are usually confirmed with a blood smear. Other blood tests may also be done.

How is malaria treated?

Malaria is treated with medicines called antimalarials. The medicine you get will depend on the area where you were bitten by an infected mosquito, the type of malaria you have, and your age and health.

Special care is needed for anyone who is pregnant, a child, very old, has other health problems, and who didn't take medicine to prevent malaria infection.

If you're going to areas with limited or no medical care, you can get medicine before traveling to bring with you in case you get malaria symptoms. This is a short-term measure until you can get medical care. Seek care as soon as you can within 24 hours after symptoms start.

The most up-to-date information about the treatment of malaria is available from the Centers for Disease Control and Prevention (CDC) website at www.cdc.gov/malaria and the World Health Organization (WHO).

How can you help prevent malaria?

If you can, avoid going to areas where malaria is common. Talk to your doctor before you go about taking preventive medicines. Start taking it before you leave on your trip. Keep taking it while you travel. When you get home, keep taking the medicine for as long as your doctor tells you to.

Protect yourself from mosquito bites, especially when you travel.

To learn more

The most current information about malaria is available from the U.S. Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO). If you are planning international travel, you can learn about the risk of malaria in the area you're traveling to by:

• Visiting the CDC website at www.cdc.gov/malaria or by calling their toll-free phone number (1-800-232-4636).
• Contacting your doctor or local health department.