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This fact sheet answers frequently asked questions about Malaria.

Malaria is a serious and sometimes fatal disease.

The basics

What is malaria?  

A parasite found in infected mosquitoes causes malaria. Each year, the United States has about 1,500 diagnosed cases. 

How does malaria spread?

Malaria mainly spreads through the bite of an infected Anopheles mosquito. Malaria is less commonly spread through blood transfusion, organ transplant, or by sharing needles or syringes contaminated with blood. An infected mother can also spread malaria to her unborn child before or during delivery.

Where is malaria found?

You can find malaria in tropical and subtropical areas. Visit the CDC website for more information.

Who is at risk for malaria?

Anyone can get malaria.

Can I donate blood if I have been in a country where there is malaria?

Blood banks, hospitals, and other facilities collecting blood establish their own blood donation guidelines. To view the CDC recommendations, go here.


What are the signs and symptoms of malaria?

The most common symptoms include fever and flu-like symptoms. This includes:

  • shaking chills
  • headache
  • muscle aches
  • tiredness

Infected people may also experience nausea, vomiting, or diarrhea. Anemia and jaundice may also occur. If left untreated, infected people can develop severe complications. 

How long do symptoms take to appear after exposure?

For most people, symptoms begin 10 days to 4 weeks after infection. However, a person may feel ill as early as 7 days or as late as 1 year after initial exposure. 


How can I prevent malaria?

If traveling to an area with malaria, talk to your health care provider about taking preventative drugs. Antimalarial drugs are not vaccines. However, they can help prevent malaria. For best results, take antimalarial drugs for the entire duration of the trip. Recommendations for antimalarial drugs differ by:

  • country of travel
  • traveler's medical history
  • age
  • drug allergies
  • pregnancy status
  • other factors

You need to start some antimalarial drugs before the start of travel to allow enough time for it to become effective. Other antimalarial drugs only need to start the day before travel. Talk to your health care provider for more details.

No antimalarial medicine is 100% protective and all medicines can have side effects. Tools, such as insect repellent, protective clothing, and mosquito bed nets, can help reduce the risk of malaria.

  • When choosing mosquito repellent, pick a product approved by the Environmental Protection Agency (EPA). Always use the product as directed and reapply when necessary
  • When weather permits, wear protective clothing such as long sleeved shirts, long pants, and socks
  • When indoors, use air conditioning or window/door screens to keep mosquitoes outside. If needed, sleep under a mosquito net

To learn more on how to keep yourself healthy during your trip, visit here


Is there a malaria vaccine?

No. There are no effective malaria vaccines. Vaccine clinical trials are ongoing. 

Is there a treatment for malaria?

Yes. Treatment should start early in the course of the disease to prevent serious illness and death. You can cure malaria with prescription drugs. The specific medicine and length of treatment depend on:

  • the type of malaria
  • the site of infection
  • whether they are pregnant
  • how sick they are at the start of treatment

Talk to your health care provider for more information.

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