This type of hepatitis is common in developing countries and has not occurred in the United States. Symptoms may include painful blisters or open sores in the genital area, which may be preceded by a tingling or burning sensation in the legs, buttocks, or genital region. The herpes sores usually disappear within a few weeks, but the virus remains in the body and the lesions may recur from time to time. HPV is a major risk factor for cervical cancer. These mosquitoes are present in the tropics and subtropics in almost all countries.
Malaria is the most deadly of all tropical parasitic diseases.
Spread by airborne droplets from the upper respiratory tract, the disease usually takes two to three weeks to appear. Pertussis caused thousands of deaths in the 1930s and 1940s, but with the advent of a vaccine, the rate of death has declined dramatically. Spread though feces and airborne particles, the poliovirus usually causes no more than a mild illness. However, some of the more serious manifestations of the disease include meningitis, which can lead to extensive paralysis. A membrane may form over the throat and tonsils, causing a sore throat.