Understanding Malaria

When a mosquito bites you, substances that can cause illness may get into your body through the bite. Some types of mosquitoes can pass on the parasite that causes malaria. Malaria is now rare in the U.S. This is because the mosquitoes that carry it have mostly been killed off. Malaria is more common in other parts of the world. There are 200 million to 300 million cases of malaria in 100 countries in the world each year. Travelers to other countries are at risk for malaria.

What causes malaria?

The parasite that causes malaria is passed to people in bites from a certain type of mosquito. It may also be spread when someone gets infected blood in a transfusion, or through sharing needles. Pregnant mothers who have malaria may pass it to their babies, but this is rare.

What are the symptoms of malaria?

Malaria can have a wide variety of symptoms. These may include:

  • High fever and restlessness

  • Chills and shivering

  • Sweating

  • Tiredness or feeling unwell

  • Headache

  • Cough

  • Body aches

  • Confusion or seizures

  • Skin or eyes that look yellow (jaundice)

  • Nausea and vomiting or diarrhea

Symptoms are usually worse in very young children and travelers. People who live in areas with malaria often get a more mild disease. Malaria can also come back after months or even years if not treated completely.

How is malaria treated?

Treatment focuses on killing the parasite that causes malaria. This is done by giving you medicine to get rid of the parasite. Other treatments work on specific symptoms that each person may have.

How can I prevent malaria?

Public health steps are used worldwide to cut down on the number of mosquitoes that can spread the illness. This can be done through chemical spraying or by removing breeding areas. If you are planning to travel to places where malaria is common, talk with your healthcare provider. You may be able to take medicines to prevent malaria. Avoiding mosquito bites in malaria areas also helps to prevent malaria. Here are some ways to avoid getting mosquito bites:

  • Put insect repellent containing DEET on exposed skin when you are outside. This is especially important in the evening. Use DEET cautiously in small children.

  • Wear long-sleeved shirts and long pants when outside.

  • Use screens on windows and mosquito netting over beds.

What are the possible complications of malaria?

Malaria can have serious complications. These can include:

  • Too few red blood cells (anemia). This can cause weakness and tiredness.

  • Damage to internal organs, especially the spleen and kidneys

  • Swelling of the brain or brain damage

  • Low blood pressure

  • Problems with blood chemistry, including low blood sugar

  • Death

When should I call my healthcare provider?

Call your healthcare provider right away if you have any of these:

  • Confusion or seizures

  • Fever of 100.4°F (38°C) or higher, or as directed

  • Pain that gets worse

  • Symptoms that don’t get better with treatment, or symptoms that get worse

  • New symptoms