Robert Wood Johnson University Hospital



What is malaria?

Malaria is a disease caused by a parasite that is transmitted to humans by the bite of an infected Anopheles mosquito. These mosquitoes are present in the tropics and subtropics in almost all countries. Nearly all cases of malaria in the U.S. are in people who have traveled internationally.

Malaria is the most deadly of all tropical parasitic diseases. After the parasites enter the body by a mosquito bite, they disappear from the circulating blood within an hour and gather in the liver. After several days, infected red blood cells (RBCs) emerge from the liver and infect other RBCs.

What are the different types of malaria parasites?

Four species of Plasmodium (single-celled parasites) can infect humans and cause illness:

Generally, only falciparum malaria is potentially life-threatening. Patients with severe falciparum malaria may develop liver and kidney failure, convulsions, and coma. Infections with P. vivax and P. ovale may cause less serious illness, but the parasites can remain dormant in the liver for many months, causing a reappearance of symptoms months or even years later.

What are the risks of acquiring malaria?

The risk of acquiring malaria depends on:

What are the symptoms of malaria?

Early stages of malaria may be similar to the flu. The following are the most common symptoms of malaria. However, each individual may experience symptoms differently. Symptoms may include:

Symptoms of malaria usually appear from seven to 30 days after the infectious mosquito bite and may resemble other medical conditions. Always consult your doctor for a diagnosis.

How is malaria diagnosed?

In addition to a complete medical history and physical examination, diagnostic procedures for malaria may include blood work to rule out other possible infections. Infected RBCs from a person's blood sample can also often be directly visualized under the microscope.

Can malaria be prevented?

Malaria can often be prevented by the use of antimalarial drugs and use of protection measures against mosquito bites.

Note: According to the CDC, vitamin B and ultrasound devices do not prevent mosquito bites.

What is the treatment for malaria?

Specific treatment for malaria will be determined by your doctor based on:

What are the CDC's recommendations for travelers?

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Online Resources of Infectious Diseases


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