MALARIA




General advice for travelers to malaria-endemic areas

Malaria is a serious parasitic infection that is transmitted to humans through the bite of an infected Anopheles mosquito. These mosquitoes are present in almost all countries in the tropics and subtropics. Anopheles mosquitoes bite during evening and nighttime hours, from dusk to dawn. Both personal protection measures and anti malarial drugs are recommended for travelers who have exposure during evening and nighttime hours in malaria risk areas.

Symptoms of illness

Symptoms of malaria include fever, chills, headache, muscle ache, and malaise. Early stages of malaria may resemble the onset of flu. Travelers who become ill with a fever during or after 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.

Disease

Travelers can still get malaria despite the use of preventive measure. Malaria symptoms can develop as early as 7 days after being bitten by an infected mosquito or as late as several months after departure from a malarious area, after anti malarial drugs have been discontinued. Malaria can be treated effectively in its early stages, but delaying treatment can have serious consequences. If left untreated, malaria can cause anemia, kidney failure, coma, and death. In spite of all protective measures, travelers occasionally develop malaria. Therefore, while traveling and up to one year after returning home, travelers should seek medical evaluation for any flu-like symptoms.

Protection measures

Malaria transmission occurs primarily between dusk and dawn. The risk of malaria depends on the traveler's itinerary, the duration of travel, and the place where the traveler will spend the evenings and nights. Protective measures include remaining in well-screened areas, using mosquito nets, and wearing protective clothes that cover most of the body. Insect repellent should be used on exposed skin. The most effective repellents contain DEET. The effect should last for about 4 hours. Travelers should use pyrethroid-containing flying insect spray in living and sleeping areas during evening and nighttime hours. Permethrin (Permanone) may be sprayed on clothing for protection against mosquitoes. When used according to directions, Permethrin will repel insects from clothing for several weeks.

Travelers at risk for malaria should take Mefloquine tablets to prevent the disease. Mefloquine should be taken one week before leaving, weekly while in the malarious area, and weekly for 4 weeks after leaving the malarious area. Chemoprophylaxis may also include Fansidar drugs depending on the area to be visited and the absence or existence of resistant strains of malaria.

Endemic areas

Malaria occurs in large areas of Central and South America, Hispaniola, sub -Saharan Africa, the Indian subcontinent, Southeast Asia, the Middle East, and Oceana. The risk of exposure is less in urban areas and during the daytime, and greater in rural areas and during the evening and nighttime hours. The risk of acquiring malaria is greater in Africa since travelers to Africa tend to spend considerable time, including evening and nighttime hours, in rural areas where malaria risk is highest.

Chloroquine/mefloquine-sensitive malaria occurs in: Mexico, Central America, far north Argentina, Paraguay, Egypt, Turkey, Syria, Lebanon, Iraq, Saudi Arabia, Kuwait, United Arab Emirates, Quatar, Bahrain.

Chloroquine/melfoquine-resistant P. falciparum malaria occurs in: Brazil, Peru, Equador, Columbia, Venezuela, Guyana, Surinam, French Guiana, Bolivia, throughout sub-Saharan, West, Central, East, and southern Africa, including Madagascar, in Yemen, Oman, Iran, Afghanistan, all of South Asia, all of Southeast Asia including Indonesia, Philippines, and southern China.

Resistance to both chloroquine and Fansidar is widespread in Thailand, Burma, Cambodia, and the Amazon basin area of South America, and resistance has also been reported in sub-Saharan Africa. Resistance to mefloquine has been confirmed in Thailand along the borders with Cambodia and Burma.

Diseases