(*PDF version) for printing.

What is malaria?

Malaria is a disease caused by a parasite that is transmitted from person-to-person by the bite of an infected Anopheles mosquito. The symptoms of malaria include fever, chills, headache, muscle aches, and malaise (a general sick feeling). Early stages of malaria may resemble the onset of influenza.

Who gets malaria?

Malaria is extremely rare in the United States, but is present in almost all countries in the tropics and subtropics. Anyone can get malaria if they are bitten by a mosquito that is carrying the parasite.

How is malaria spread?

Malaria is spread by mosquito bites. Cases of malaria that occur in the United States are nearly always among persons who have traveled to places where malaria is common.

How soon after exposure do symptoms appear?

Malaria symptoms can develop as early as 6-8 days after being bitten by an infected mosquito or as late as several months after departure from an area where malaria is present, after antimalarial drugs are discontinued.

How is malaria diagnosed?

Malaria is diagnosed by the demonstration of malaria parasites in a blood smear. Questions about blood smears should be directed to the Centers for Disease Control and Prevention.

What is the treatment for malaria?

Malaria can be treated with specific antimalarial drugs. It can be treated effectively in its early stages, but delaying treatment can have serious consequences.

Travelers who become ill with a fever during or after a travel in a malaria risk area should seek prompt medical attention and should inform their physician of their recent travel history. Neither the traveler nor the physician should assume that the traveler has 'the flu' or some other disease without doing a laboratory test to determine if the symptoms are caused by malaria.

How can malaria be prevented?

The risk of malaria in the United States is virtually nonexistent. Malaria may be prevented in travelers who visit areas where malaria is present if they use antimalarial drugs and personal protection measures (for example, mosquito netting and insect repellents). The risk of malaria depends on the traveler's itinerary and activities, and their duration of travel. Anopheles mosquitoes bite during nighttime hours, from dusk to dawn, so it is especially necessary to be aware of possible exposure during these hours.

It is important to remember that travelers can still get malaria, despite use of antimalarial drugs and other prevention measures.

Where can I get more information?

UTAH DEPARTMENT OF HEALTH
BUREAU OF EPIDEMIOLOGY
August 2001

This fact sheet was based on the Centers for Disease Control and Prevention's Malaria: General Information sheet (last updated 7/12/96) and Centers for Disease Control and Prevention. Case definitions for infectious conditions under public health surveillance. MMWR 1997; 46 (No. RR-10):22-23.