In 2005, a tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap; Adacel) was approved in the United States for use in adults and adolescents. The Advisory Committee on Immunization Practices (ACIP) now recommends the routine use of Tdap among adults 19 to 64 years of age who have not already received a dose of Tdap. The ACIP recommendations are intended to decrease pertussis-related morbidity among adults, to maintain the standard of care for tetanus and diphtheria prevention, and to reduce transmission of pertussis to infants and in health care settings.

Routine Vaccination

Patients 19 to 64 years of age who received their most recent dose of tetanus and diphtheria toxoid (Td) at least 10 years earlier should be given a single dose of Tdap for active booster vaccination against tetanus, diphtheria, and pertussis. If less than 10 years has passed since the previous dose of Td was administered, a single dose of Tdap is appropriate to protect patients against pertussis. This is especially true in patients at increased risk of pertussis or its complications; the benefit of a single dose of Tdap at an interval of less than 10 years will likely outweigh the risk of adverse reactions to the vaccine. In addition, an interval as short as two years between Td and Tdap is considered safe.

In patients who have not previously received Tdap and who need a vaccine containing tetanus toxoid as part of wound management care, Tdap is preferred to Td.

ADULTS IN CONTACT WITH INFANTS

Compared with adults, infants younger than 12 months are at a higher risk of hospitalization from pertussis-related complications, and they have a higher risk of death. Therefore, vaccinating adults who come into con tact with these infants may reduce the risk of transmitting pertussis (see accompanying table).

To protect against pertussis, adults who have not previously received Tdap and who are in contact or anticipate contact with infants younger than 12 months should receive a single dose of Tdap at an interval of less than 10 years since their most recent Td vaccination These adults should receive the Tdap vaccine at least two weeks before coming into contact with an infant. An interval as short as two years from the previous dose of Td is recommended to reduce the risk of systemic and local reactions after the vaccination, but shorter inter vals may be used, if appropriate.

WOMEN WHO ARE PREGNANT OR MAY BECOME PREGNANT

Ideally, women should be vaccinated with Tdap before becoming pregnant. If this is not possible, they should receive a single dose of Tdap in the immediate postpar tum period. It should be administered before the patient is discharged from the hospital or birthing center.

HEALTH CARE PROFESSIONALS

Health care professionals who deal directly with patients should receive a single dose of Tdap. An interval as short as two years from the previous dose of Td is recommended for administration of the Tdap vaccine in this population. Health care professionals without direct patient contact should be given a single dose of Tdap to replace the next scheduled Td vaccine at an interval of 10 years or less since the previous dose of Td.

Administering the Vaccine

A single dose of Tdap is 0.5 mL and is administered intra-muscularly, preferably into the deltoid muscle. If another vaccine is indicated in addition to Tdap, the vaccines should be administered simultaneously but at separate anatomic sites and with different syringes.

Special Situations

SETTINGS WITH INCREASED RISK OF PERTUSSIS

During outbreaks of pertussis or in communities with increased pertussis activity, health care professionals should consider administering Tdap to adults at intervals of less than 10 years since the most recent dose of Td or tetanus toxoid if the patient has not previously received Tdap.

HISTORY OF PERTUSSIS

Adults with a history of pertussis should receive a single dose of Tdap. Administration of the vaccine to these patients presents no theoretical safety concern.

WOUND MANAGEMENT

Adults receiving wound management care should be given a tetanus toxoid–containing vaccine and tetanus immune globulin to prevent tetanus. Tdap is preferred to Td if these patients were vaccinated at least five years earlier but have not received Tdap. However, if Tdap was previously administered, Td should be given if a vaccine containing tetanus toxoid is indicated for wound care.

UNKNOWN VACCINATION HISTORY

Adults with unknown vaccination histories or who were never vaccinated against tetanus, diphtheria, or pertussis should be given a series of three vaccinations that contain tetanus and diphtheria toxoids. The preferred dosing schedule is a single dose of Tdap, followed by a dose of Td at least four weeks later and another dose of Td six to 12 months later. Tdap also can substitute for any one of the doses of Td in the three-dose series.

INCOMPLETE VACCINATION HISTORY

Adults who received other incomplete vaccination series against tetanus and diphtheria should be vaccinated with Td, Tdap, or a combination of the two to complete the three-dose primary series of tetanus and diphtheria toxoid–containing vaccines. A single dose of Tdap can be used in the series.

ADULTS 65 YEARS AND OLDER

Tdap is not licensed for use in adults 65 years and older. A dose of Td every 10 years is recommended for protection against tetanus and diphtheria and as needed for wound management care.

Contraindications

Tdap is contraindicated in adults who have a history of serious allergic reaction to any component of the vaccine. They should be referred to an allergy subspecialist to determine whether they can safely receive tetanus toxoid vaccinations.

The vaccine is contraindicated in adults with a history of encephalopathy not attributed to an identifiable cause within seven days of administration of a vaccine containing pertussis components. Because the contraindication is only for the pertussis components, these patients should receive Td instead of Tdap.

Precautions

If a patient may be at risk of developing a serious adverse reaction to a vaccine, health care professionals should evaluate the benefits and risks of administering Tdap.

Tdap should be deferred in patients with moderate to severe acute illness, with or without fever, until the illness resolves. Tdap administration should also be deferred in patients with an unstable neurologic condition and those with a history of an Arthus reaction following a previous dose of a vaccine containing tetanus toxoid, diphtheria toxoid, or both.