What is malaria ?

Malaria is a serious disease that spreads when you’re bitten by a mosquito infected by tiny parasites. When it bites, the mosquito injects malaria parasites into your bloodstream. Malaria is caused by the parasites, not by a virus or by a type of bacterium.

If it isn’t treated, malaria can cause severe health problems such as seizures, brain damage, trouble breathing, organ failure and death.

The disease is rare in the U.S., with about 2,000 cases per year. If you’re traveling to an area where malaria is common, talk to your healthcare provider about ways you can prevent being infected. People who are infected and travel to the U.S. can spread the disease if a mosquito bites them and then bites someone else.

How common is malaria?

Malaria is common in tropical areas where it’s hot and humid. In 2020, there were 241 million reported cases of malaria throughout the world, with 627,000 deaths due to malaria. The majority of these cases occur in Africa and South Asia.

Symptoms and Causes

What causes malaria?

When a mosquito bites someone who has malaria, the mosquito becomes infected. When that mosquito bites someone else, it transfers a parasite to the other person’s bloodstream. There, the parasites multiply. There are five types of malaria parasites that can infect humans.

In rare cases, people who are pregnant and who have malaria can transfer the disease to their children before or during birth.

It’s possible, but unlikely, for malaria to be passed through blood transfusions, organ donations and hypodermic needles.