The Centers for Disease Control and Preventions (CDC) Advisory Committee on Immunization Practices (ACIP) at its recent meeting (Oct. 26-27) in Atlanta, voted to recommend that adults from 19 to 64 years of age be vaccinated with a newly licensed adult booster tetanus, diphtheria and pertussis (whooping cough) vaccine (Tdap).
Under the ACIP recommendation, the Tdap vaccine would replace the currently recommended tetanus-diphtheria vaccine that is used as the adult booster vaccine. The new vaccine helps protect adults from pertussis, an illness with severe and prolonged cough. It also reduces the risk of transmitting pertussis to infants.
The ACIP recommended that adults receive a booster dose of Tdap vaccine against tetanus, diphtheria and pertussis if they have not received a tetanus and diphtheria (Td) booster dose in 10 or more years. Adults should receive a single dose of Tdap to replace a single dose of Td. Pertussis affects an estimated 600,000 adults every year, aged 20 to 64 years, and can result in weeks of coughing, cracked ribs from severe coughing spells, pneumonia, and other complications.
Tdap should also be given to adults who will have close contact with an infant less than 12 months of age, ideally at least one month before beginning close contact with infants. In situations when it is important to protect against pertussis, intervals shorter than 10 years since the last Td vaccination may be used. A two-year interval between Td and Tdap is suggested to reduce the risk of reactions following vaccination.
Infants less than 12 months of age have a high risk of pertussis-related complications, hospitalizations and death. Vaccinating adult contacts may reduce the risk of transmitting pertussis to infants said Dr. Steve Cochi, acting director of CDCs National Immunization Program. Although pertussis is most serious in infants, it can also be serious in adults. Even adults who dont typically come in contact with young children should be vaccinated.
In June, the ACIP recommended that adolescents 11 and 12 years of age be given Tdap in place of the tetanus-diphtheria (Td) booster typically given to adolescents. The committee also recommended that Tdap be given to adolescents 13 through 18 who missed the 11 to 12 year dose of Td. Adolescents 11 to 18 who have already been vaccinated with Td are encouraged to receive a dose of Tdap at intervals shorter than 10 years, to add protection against pertussis.
Most reported pertussis cases among adolescents and adults occur because of decline in protective immunity over time. Immunity against pertussis wanes five to 10 years after the last childhood vaccination.
Infants acquire pertussis, often from siblings and parents at home, when they are still too young to be vaccinated against the infection, or when not yet vaccinated. ACIP recommends that children be vaccinated against diphtheria, tetanus and pertussis at two, four, six, and 15 to 18 months of age, and at four to six years of age. DTaP is the vaccine used for children under 7 years of age.
Pertussis can be very severe in infants. It is important that parents vaccinate their infants and children on time to prevent this serious and potentially life-threatening disease, said Cochi.
The Food and Drug Administration (FDA) recently licensed two Tdap vaccines for adolescents and adults in the United States. BOOSTRIXÂ®, manufactured by GlaxoSmithKline Biologicals, was licensed by the FDA on May 3, 2005, for use in adolescents 10 through 18 years of age. The second, ADACEL, manufactured by sanofi pasteur, was licensed on June 10, 2005, for persons 11 through 64 years of age. These are the first pertussis vaccines licensed for use in adolescents and adults.
Reported pertussis cases increased throughout the 1990s and increases have continued to the present. Cases of pertussis were reduced by more than 90 percent following introduction of diphtheria, tetanus and pertussis (DTP) vaccine in the 1940s. Reported pertussis cases have increased from a low of 1,020 cases in 1976 to 25,827 cases in 2004, a 40-year high. Reported pertussis-related deaths among infants increased from about 10 per year in the 1990s to about 20 per year during this decade.