What are malaria tests?

Malaria is a serious disease caused by a parasite. Malaria parasites are tiny single-celled life forms. They live and reproduce in the red blood cells of humans. This destroys the red blood cells, which makes you sick.

In most cases, people get malaria when they are bitten by mosquitos that are infected with the parasite. At first, malaria symptoms may be much like the flu. In certain cases, the disease can become life-threatening if it isn't treated quickly. But medicines can usually cure malaria.

Malaria tests look for signs of a malaria infection in a sample of your blood. The tests can diagnose malaria early so the disease can be cured before it causes serious illness. Malaria testing is used if you have symptoms of malaria and you have recently been in parts of the world where malaria is common.

Malaria is rare in the United States. It's mostly found in warm, humid parts of the world. The highest number of cases are in parts of Africa south of the Sahara Desert. In the U.S., most cases are in people who have traveled in tropical and subtropical areas where mosquitos spread a lot of disease.

In rare cases, malaria is spread through contact with the blood of an infected person. This may happen during blood transfusions, organ transplantations, or sharing needles and other items used to inject drugs. If you're pregnant when you have malaria, it's possible to give it to your unborn baby. But malaria isn't catchy like a cold or flu. And it can't be spread through sex or being near someone who has malaria.

Other names: malaria blood smear, malaria rapid diagnostic test, malaria by PCR

What are they used for?

Malaria tests are used to diagnose malaria. There are different types of malaria parasites that infect humans. The tests can tell which type you have. This information is important for choosing the right treatment to cure the disease.

Malaria testing is also used to help control the spread of the disease. That's because mosquitos become infected with malaria parasites when they bite a person who has malaria. Then they spread the disease by biting others. Testing helps you get treatment to get rid of the parasites before more mosquitos get the parasite by biting you.

Why do I need a malaria test?

You may need this test if you have symptoms of malaria and you've been in an area where malaria is common. Depending on the type of malaria parasite, symptoms usually begin between 7 to 30 days after an infected mosquito bites you. But symptoms can take up to a year to appear. So, if you have symptoms, remind your health care provider about any places you've traveled over the past 12 months.

The first symptoms of malaria are often like having the flu, and may include:

• Fever
• Chills
• Fatigue
• Headache
• Muscle pain
• Nausea and vomiting

If you are infected with certain types of malaria parasites, you may have symptoms which come and go every two or three days.

Without treatment, malaria can quickly become a life-threatening disease. As it gets worse, the symptoms will depend on the type of parasite you have. They may include:

• Anemia
• Jaundice
• Kidney failure
• Seizures
• Mental confusion
• Coma

What happens during a malaria test?

Your provider will examine you and ask about your symptoms and recent travels. If your provider thinks you could have malaria, you will have a blood test to check for signs of malaria parasites.

During a blood test, a health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.

There are two types of blood tests to diagnose malaria. Both tests are done when possible:

• Blood smear test. For this test, a drop of your blood is put on a special slide. A laboratory professional will examine the slide under a microscope to look for parasites. This test can identify all types of malaria parasites.
• Rapid diagnostic test (RDT). This test looks for certain proteins that come from malaria parasites. It can provide results in under 15 minutes, but an RDT can't accurately show which type of malaria parasite you have. This information affects your treatment. So, if an RDT shows that you have malaria, a blood smear is needed, too.

Your provider may order other blood tests, such as a complete blood count (CBC). If you do have malaria, the results of these tests will show how the disease is affecting you.

Will I need to do anything to prepare for the test?

You don't any special preparations for a malaria test.

Are there any risks to the test?

There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.

What do the results mean?

If the results of your malaria test are negative, it means that no signs of malaria parasites were found in your blood sample. But this doesn't rule out malaria. That's because the number of malaria parasites in your blood can vary over time. If you have a negative result, more blood samples are usually taken every 12-24 hours for a total of 3 sets of tests. If these test results are all negative, you probably don't have malaria.

If the results of your malaria test are positive, it means you have malaria. Your provider will prescribe medicine right away. The medicine you take will depend on:

• The type of malaria parasite you have
• Whether the parasite has become resistant to certain medicines
• Your symptoms and medical history
• Whether you are pregnant

When treated early, malaria can usually be cured. If your provider strongly believes you have a serious case of malaria, you may start treatment before test results confirm you have the disease.

Learn more about laboratory tests, reference ranges, and understanding results.

Is there anything else I need to know about malaria tests?

If you will be traveling to an area where malaria is common, talk with your provider before you go. You may be able to take medicine that can help prevent malaria.

You can also take steps to protect yourself against mosquito bites. This may reduce your risk of getting malaria and other infections transmitted by mosquitos.