Infectious Diseases - Prevention Through Immunization

Many infectious diseases can be prevented by immunizations. According to the National Immunization Program of the CDC, there are fourteen diseases that can be prevented by vaccination and for which vaccinations are recommended. Some other diseases are preventable by vaccination, but vaccination is not recommended for everyone because the risk of contracting these diseases is not great enough to warrant widespread immunization. They include anthrax, meningococcal infection, rotavirus, and smallpox. (See Figure 2.1 in Chapter 2 for a schedule of childhood immunizations and Figure 7.1 for immunizations recommended for adolescents and adults.) The fourteen vaccine-preventable diseases are as follows:

• Diphtheria—This bacterial infection causes potentially fatal respiratory infections that are treated with antibiotics. People diagnosed with diphtheria are isolated until cultures are negative to prevent the spread of the disease.
• Haemophilus influenza type b (Hib)—This bacterial infection causes respiratory infections and other diseases, such as meningitis.
• Hepatitis A—The virus is spread through fecal (stool) or oral routes, though it may also be transmitted via blood or sexual contact. Outbreaks usually occur from contaminated food and water; military workers, children in day care centers, and their care providers are considered at high risk.
• Hepatitis B—It is transmitted by blood, sexual contact, or from mother to unborn child; intravenous drug users, gay men, and health care workers are at high risk.
• Influenza (flu)—This viral infection produces sudden fever, muscle aches, and respiratory infection symptoms.
• Lyme Disease—This bacterial disease is spread by infected ticks and produces fever, headache, joint and muscle pain, swollen lymph nodes, and a distinctive circular skin rash. It may be treated with antibiotics or prevented by vaccine.
• Measles—This highly contagious viral disease produces red circular spots on the skin.
• Mumps—This highly contagious viral disease produces swelling of the parotid glands.
• Pertussis (whooping cough)—This bacterial infection causes illness marked by spasms of coughing.
• Pneumococcal—This bacteria causes pneumonia, an inflammation of the lungs.
• Poliomyelitis (polio)—A viral disease, polio causes fever, atrophy (wasting) of skeletal muscles, and paralysis.
• Rubella (German measles)—This viral infection is usually mild in children but can seriously harm an unborn child when contracted by a woman early in her pregnancy.
• Tetanus—Bacteria produce a toxin that causes victims to have painful muscle spasms.
• Varicella (chickenpox)—This is a highly contagious viral disease marked by skin eruptions of fluid-filled lesions that itch.

FIGURE 7.1
Recommended adult immunization schedule, 2003–04, by age group

Until the 1960s, for example, poliomyelitis (polio) was a serious threat to children, adolescents, and even adults. After the discovery of vaccines to prevent this FIGURE 7.1
Recommended adult immunization schedule, 2003–04, by age group FIGURE 7.1
Recommended adult immunization schedule, by age group, 2003–04 disease, massive worldwide immunization programs were carried out, and by 1994 an international health commission declared that indigenous (in-country) transmission of wild (not developed in laboratories or contained in vaccines) poliovirus had been stopped in the Western hemisphere. The last reported case of polio documented in the United States was 1979, and the goal for global eradication is 2005.

The incidence of polio also has decreased greatly in other parts of the world. At one time, polio killed or crippled 500,000 people worldwide every year. The number of reported cases worldwide has decreased dramatically because most governments had made great strides toward tracking new infections and vaccinating children against the disease. The last isolate of type 2 polio was found in India in 1999.