What is malaria?
Malaria is a disease that causes a fever, chills, and muscle pain. You can get it from a bite from an infected mosquito. Malaria is very rare in the United States. It's most often found in Africa, Southern Asia, Central America, and South America.
Symptoms may come and go in cycles. Malaria may also cause more serious problems. These include damage to the heart, lungs, kidneys, or brain. It can even be deadly. But you can do a lot to prevent this infection.
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.
- 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 kind of malaria parasite that you have.
In rare cases, malaria can affect the brain or spinal cord and cause seizures or loss of consciousness. The most serious types of malaria infection can be deadly.
The time from when you get infected until symptoms appear is usually 7 to 30 days. But with some infections, signs of illness 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, they will use a blood smear to check for the disease. During this test, a sample of blood is placed on a glass slide, prepared, 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 type of parasite you have, your age and health, and other things.
If you're going to areas where there is no medical care, you can get medicine 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 (best is within 24 hours).
The most up-to-date information about the treatment of malaria is available from the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO).
What can you do to prevent malaria?
- If you can, avoid going to areas where malaria is common. Talk to your doctor before you go.
- Prevent mosquito bites when you go to areas where malaria is common.
- After dark, stay indoors in a screened or air-conditioned room.
- Wear protective clothing. Wear long pants and long-sleeved shirts.
- Use an insect repellent with DEET. Experts suggest that repellent with 10% to 30% DEET is safe to use with children older than 2 months. Read and follow all instructions on the label.
- Use bed nets (mosquito netting) sprayed with or soaked in permethrin or deltamethrin. These chemicals repel or kill mosquitoes.
- Use flying-insect spray indoors around sleeping areas.
- Take medicine to prevent malaria. 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.
Current as of: February 9, 2022
Author: Healthwise Staff
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Elizabeth T. Russo MD - Internal Medicine
W. David Colby IV MSc, MD, FRCPC - Infectious Disease