Immunizations - Measles, Mumps, and Rubella

Diphtheria, Tetanus, and Pertussis

Diphtheria. Diphtheria is caused by the bacterium Corynebacterium diphtheriae, which can occur as either a toxic or nontoxic strain. When only the skin is involved, it is known as cutaneous diphtheria, and is likely to be a nontoxic strain. If the toxic strain affects the mucus linings in the body, such as the throat, diphtheria becomes life threatening. Between 1900 and 1925, diphtheria infected 200,000 people every year and killed between 5 - 10% of them, mostly the very young and very old. Because of immunizations, only 6 cases were reported in the United States between 2000 and 2003, inclusive.

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Tetanus. Tetanus is a disease that causes severe muscular contractions and convulsions. It is caused by a powerful toxin secreted by the bacterium Clostridium tetani. The bacterium is anaerobic, which means it lives without oxygen. People become infected by this dangerous bacterium through skin wounds. It is fatal in 15 - 40% of cases. Only 168 cases were reported in the U.S. between 2000 and 2007, inclusive, mostly in adults. One case, however, occurred in a 12-year-old boy whose parents refused to vaccinate him.

Pertussis. Pertussis (whooping cough) was a very common childhood illness throughout the first half of the 1900s. The disease is very easily spread from one person to another, and it is most severe in babies. Because of immunizations, cases of whooping cough in the U.S reached an all-time low of 1,010 in 1976. The incidence has risen recently, with 25,827 cases reported in 2004, but dropped to 10,454 in 2007, the last year reported by the World Health Organization.

The benefit of the vaccine wears off by adolescence. Therefore, more cases are seen in adults. Such cases may be greatly underreported. The younger a whooping cough patient is, the higher the risk for severe complications, including pneumonia, seizures, and even death. Children younger than 6 months are at particular risk because even with vaccination, their protection is incomplete due to an immature immune system.