Though only rarely fatal, this disease, in even a mild form, can delay a trip in nightmarish fashion - shaking, cold sweats, and diarrhea straight out of Dr. Livingston's worst nightmares. Most strains will not cause death, but can still prove difficult to cure. Early symptoms typically resemble the flu - fever, chills, sweating, headaches, muscle aches, and diarrhea, for example. Onset of symptoms after the infectious bite typically occurs within seven days, though it can take as long as 21. Once acquired, malaria hangs on like a pit bull.
Some travelers suffer malarial relapses periodically for the rest of their lives.
Of the four strains of malaria that thrive in humans, the only fatal version is Plasmodium falciparum , which causes cerebral malaria. At its worst, this disease explodes so many blood cells at once that the victim's bloodstream becomes literally choked with dead material. When to worry Malaria parasites tend to hang out in warm, humid, lowland regions. Speaking really broadly, you should worry most about South and Central America, sub-Saharan Africa, Asia, and Melanesia. However, you absolutely must check for specific local information when planning your itinerary.