A compromised immune system, which can result from diseases such as AIDS or treatment of diseases such as cancer, may allow organisms that are ordinarily harmless to proliferate and cause life-threatening illness. Some infections, such as measles, malaria, typhus and yellow fever, affect the entire body. Most infections, however, affect only one organ or system of the body. The most frequent local infections, including the common cold, occur in the upper respiratory tract. Other common sites of infection include the digestive tract, the lungs, the reproductive and urinary tracts, and the eyes and ears.
Modern vaccines are among our most effective strategies to prevent disease.
Many devastating diseases can now be prevented through aggressive immunization programs. Travelers to foreign countries may require vaccinations against yellow fever, cholera, typhoid fever and hepatitis. Public Health Measures. Measures that assure clean water supplies, adequate sewage treatment, and sanitary handling of food and milk also are important to control the spread of infectious disease. The fight against infectious diseases requires worldwide surveillance by physicians, scientists and public health officials who gather information on communicable diseases, report new or resurgent outbreaks of disease, and develop standards and guidelines for treating and controlling disease.