Pertussis vaccines are highly effective, strongly recommended, and save countless infant lives every year. Though the protection they offer lasts only a few years, they are given so that immunity lasts through childhood, the time of greatest exposure and greatest risk. The immunizations are given in combination with tetanus and diphtheria immunizations, at ages 2, 4, and 6 months, and later at 15�18 months and 4�6 years.
The short term effectiveness of the vaccines and the presence of B. pertussis infection in adults and adolescents who may transmit the bacteria to infants have caused many in the medical field to call for booster immunizations at later ages. Although Canada, France, the U.S. and Germany now have approved booster shots for adolescents, adults, or both, other countries adhere to the tradition of discontinuing pertussis vaccination after the age of seven, from concerns that there are side effects associated with the first available "whole-cell" pertussis immunizations that tended to increase with age. The whole-cell vaccine is still used in poor countries, since it is cheaper than the newer and safer acellular formulation.
The decision to resume vaccinating teens and adults reflects in part that the newer acellular vaccine, known as DTaP, has greatly reduced the incidence of adverse effects observed with the earlier "whole-cell" pertussis vaccine. An acellular vaccine preparation for adults and adolescents has been approved in Canada, Europe, and the United States. In the U.S., the Food and Drug Administration has authorized both the use of the vaccines Boostrix for 10-18 year olds and Adacel for 11-64 year olds. These vaccines are recommended for all teens and adults within the indicated age ranges, except for those with a history of adverse reaction to the whole-cell pertussis vaccines. The most serious side-effects of traditional "whole-cell" pertussis immunizations were neurological: and included seizures and hypotonic episodes.
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