Malaria and Travelers

by CDC

(Page 10 of 14)

Countries with Malaria Risk

Travelers to sub-Saharan Africa have the greatest risk of both getting malaria and dying from their infection. However, all travelers to countries with malaria risk may get this potentially deadly disease.

Malaria is transmitted in

• large areas of Central and South America
• the island of Hispaniola (includes Haiti and the Dominican Republic)
• Africa
• Asia (including the Indian subcontinent, Southeast Asia and the Middle East)
• Eastern Europe
• and the South Pacific

What Determines Your Individual Risk

All visitors to malaria risk areas are at risk of getting malaria; however, many factors determine the risk to an individual traveler. Even in the same locale, these factors can vary widely over time. From year to year, conditions such as amount of rainfall, the number of mosquitoes, and the number of infected persons in the area will change and may produce a different level of risk than previously seen.

Factors that determine a traveler's risk include:

Unaware of malaria risk areas

Many U.S. travelers, their healthcare providers, and tour companies may be unaware that their travel itinerary includes malaria risk areas.

Amount of malaria in the area to be visited

Most malaria transmission occurs in rural areas, although malaria occurs in urban areas in many countries. Low altitudes with warm temperatures allow for larger populations of infective mosquitoes. Transmission is generally higher in Africa south of the Sahara than in most other areas of the world; in 2002, 73% of imported malaria cases among U.S. and foreign civilians occurred in persons who traveled to Africa.

Time of the year

Seasons with more rainfall and higher temperatures will have more malaria transmission than colder, drier seasons. However, in most tropical and semi-tropical countries, transmission may occur even during cooler months or periods of less rainfall.

Type (species) of malaria parasite present in the area

While all species of malaria parasites can make a person feel very ill, Plasmodium falciparum causes severe, potentially fatal malaria. Persons who travel to areas where P. falciparum malaria is present should be extra careful to take their antimalarial drug and to prevent mosquito bites.

Nighttime exposure to mosquito bites

Because the mosquito that transmits malaria bites at night, travelers who are frequently out of doors between dusk and dawn will be at greater risk for malaria.

Preventive measures taken by travelers

Individual measures, such as taking an effective antimalarial drug and preventing mosquito bites, are the most important factors in minimizing risk. While other risk factors may be difficult to change or avoid, travelers can greatly reduce their risk of malaria by following recommended travel precautions.

Immunity or lack of immunity to malaria

Because malaria was eliminated from the United States in the late 1940s, most residents have never developed resistance (immunity) to the disease. Malaria infection in a non-immune person can quickly result in a severe and life-threatening illness.

In addition, many healthcare providers and laboratories in the United States rarely see cases of malaria and may be unfamiliar with the diagnosis and treatment of the disease, and this can delay effective treatment.

How to Protect Yourself

This picture shows some things that travelers can use to protect themselves against malaria: malaria pills; insect repellent; long-sleeved clothing; bednet; and flying insect spray.(Not shown, but also protective: air conditioned or screened quarters.)

Know the Facts

Every year, millions of United States residents travel to countries where malaria is present; about 800 cases of malaria are diagnosed in these returning travelers each year. From 1985-2002, 78 U.S. travelers died from malaria.

Persons who are traveling to malaria risk areas can almost always prevent this potentially deadly disease if they correctly take an effective antimalarial drug and follow measures to prevent mosquito bites.

Know the Symptoms

Despite these protective measures, travelers may become infected with malaria. Malaria symptoms can include:

• fever
• chills
• headache
• flu-like symptoms
• muscle aches
• fatigue
• low blood cell counts (anemia)
• yellowing of the skin and whites of the eye (jaundice)

If not promptly treated, infection with Plasmodium falciparum, the most harmful malaria parasite, may cause coma, kidney failure, and death.

When Symptoms Appear, Seek Immediate Medical Attention

Malaria is always a serious disease and may be a deadly illness. Travelers who become ill with a fever or flu-like illness either while traveling in a malaria-risk area or after returning home (for up to 1 year) should seek immediate medical attention and should tell the physician their travel history.

About the Author

www.cdc.gov
The Centers for Disease Control and Prevention (CDC) is one of the 13 major operating components of the Department of Health and Human Services (HHS), which is the principal agency in the United States government for protecting the health and safety of all Americans and for providing essential human services, especially for those people who are least able to help themselves.