infantum ) Before the diphtheria vaccine came into general use 40 years ago. 80 percent of adult Americans were immune to diphtheria because they had had some form of the illness in childhood. This situation no longer exists, so adults should receive booster shots of diphtheria vaccine every ten years. Serious reactions to the diphtheria vaccine are rare. Tetanus. Tetanus, or lockjaw, is a serious disease of the nervous system that is caused by a bacterium that can enter the body through a wound-even a minor wound like a scratch or an insect bite. Cases of tetanus are reported every year. The vaccine is thoroughly safe and effective. However, its protection weakens over the years, and booster shots are necessary. Medical opinion differs as to how often boosters should be given. The American Academy of Pediatrics states that after receiving a booster at the age of four to six years, a person should receive a booster every ten years for life. The American College of Surgeons believes that boosters are necessary every five years to ensure protection from tetanus that results from the type of minor wound that is unlikely to be treated by a doctor. As a general rule, if your child receives a relatively clean wound, such as one from a kitchen utensil, you should be sure that he has had a booster within the past ten years: but if he receives a "dirty" wound (for example, a wound from a nail or any wound that happens outdoors). you should check to see that he has received a booster within the past five years. Adults should receive boosters at least every ten years. Whooping cough. Whooping cough is more common than many parents (and doctors) realize. It is a highly contagious infection of the respiratory tract, which gets its name from the severe, strangling cough that develops as the disease progresses. Whooping cough vaccine is the most uncertain of the three components of the DTP vaccine, because it does not give complete immunity. There have been extremely rare instances of brain damage following its use, but in some of these cases the damage was caused by faulty administration of the vaccine rather than by the vaccine itself. The vaccine may also cause a brief reaction of fever. For these reasons, routine boosters are not recommended after the child receives a booster at the age of four to six years. However, the mortality rate among infants under age one who contract whooping cough and the possibility of complications in older children are high enough to exceed by far the minimal risk of the vaccine. In England, serious reactions to the vaccine were sufficiently frequent at one point to persuade the medical profession to suspend its use. However, because of the increasing incidence of whooping cough and its severe complications, immunization has now been reinstituted in England. infantum