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.
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.
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
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.
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,
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.