The virus enters the body through the mouth and invades the bloodstream. If it enters the central nervous system, it attacks motor neurons and can cause lesions that result in paralysis. The following immunizations or pills, together with the 'Low Risk' vaccines above, are recommended or required for 'High Risk' destinations. Malaria is a protozoan infection characterized by chills, fever, sweating, and anemia, with chronic relapses. In 1898 it was discovered that malarial parasites are transmitted to humans by the bite of the anopheles mosquito,widespread in tropical Africa, Central America, and Southeast Asia.
Prevention involves prescription drugs and insect repellents.
Typhoid fever is caused by the bacterium Salmonella typhi , which enters the body in water or food contaminated with the feces or urine of a carrier of the disease. After an incubation period of 7 to 21 days, the illness begins with fever, lethargy, headache, and loss of appetite. Increasing weakness and abdominal discomfort develop during the second week, when a rose-colored skin rash may appear. Intestinal bleeding or perforation may occur in the second or third week and can be fatal. Typhoid vaccine consists of 4 capsules taken orally on alternate days and must be completed 2 weeks before starting any anti-malaria pills.