When to administer Td (tetanus and diphtheria) vaccine versus Tdap (tetanus, diphtheria, and pertussis) vaccine?

From the Guidelines

Tdap vaccine should be administered to adolescents at age 11-12 years and to adults who have never received it, while Td is used as a booster every 10 years after the initial Tdap. Pregnant women should receive Tdap during each pregnancy, preferably between 27-36 weeks gestation, regardless of prior vaccination history 1. For wound management, Tdap is preferred over Td if the patient has never received Tdap previously. If a patient has already had Tdap, then Td is appropriate for wound prophylaxis if more than 5 years have elapsed since the last tetanus toxoid-containing vaccine. Some key points to consider when deciding between Td and Tdap include:

• The patient's age and vaccination history
• The presence of any underlying medical conditions
• The risk of exposure to pertussis
• The potential for adverse reactions to the vaccine The side effect profiles are similar, with both vaccines potentially causing mild pain, redness, or swelling at the injection site, along with low-grade fever and body aches that typically resolve within 1-2 days 1. It's also important to note that the Advisory Committee on Immunization Practices (ACIP) recommends that either Tdap or Td vaccines can be used in situations where only Td vaccine had been recommended previously 1. In general, the decision to use Td or Tdap should be based on the individual patient's needs and circumstances, taking into account the latest recommendations from the ACIP and other relevant guidelines 1.

From the FDA Drug Label

Diphtheria and Tetanus Toxoids and Acellular Pertussis Vaccine (DTaP) or a DTaP-containing vaccine is recommended for immunization of infants and children 6 weeks through 6 years of age. Diphtheria and Tetanus Toxoids Adsorbed should be used in instances where the pertussis vaccine component is contraindicated.

The decision to administer Td (tetanus and diphtheria) vaccine versus Tdap (tetanus, diphtheria, and pertussis) vaccine depends on the patient's age and the presence of any contraindications to the pertussis component.

• Tdap is recommended for infants and children 6 weeks through 6 years of age.
• Td should be used in instances where the pertussis vaccine component is contraindicated 2.

From the Research

Administration Guidelines for Td and Tdap Vaccines

The decision to administer Td (tetanus and diphtheria) vaccine versus Tdap (tetanus, diphtheria, and pertussis) vaccine depends on several factors, including the patient's age, health status, and previous vaccination history.

• For adults aged 18-64 years, Tdap is recommended as a replacement for a single decennial dose of Td vaccine, as stated by the Advisory Committee on Immunization Practices (ACIP) in 2005 3.
• Tdap may be used to protect against pertussis even when <10 years have passed since the most recent tetanus vaccination.
• For adults with infant contact and health-care personnel (HCP) with direct patient contact, the single recommended Tdap dose is suggested to be administered as soon as 2 years after the last tetanus vaccination 3.

Special Considerations

• Health-care providers should recommend Tdap vaccination to adults aged 18-64 years whose most recent tetanus vaccination was ≥10 years prior; the interval for HCP and persons with infant contact can be as short as 2 years 3.
• A study found that a repeat dose of Tdap vaccine 10 years after the first dose was well tolerated and immunogenic in adults, with noninferiority criteria met for all antigens except for anti-FIM 4.
• Another study suggested that Tdap can be safely administered at intervals of ≥18 months since a previous TD/Td vaccine, with only slight increases in injection site events with decreasing interval since a previous immunization 5.

Vaccine Characteristics

• Reduced-antigen, combined diphtheria, tetanus, and acellular pertussis vaccine (Tdap) is indicated for booster vaccination against diphtheria, tetanus, and pertussis in individuals from age four years onwards in Europe and from age 10 years onwards in the US 6.
• Tdap contains reduced quantities (10-50%) of all toxoids and antigens, which are adsorbed to either ≤0.39 mg/dose (US licensed formulation) or 0.5 mg/dose (rest-of-world formulation) of aluminium adjuvant 6.
• Tdap is highly immunogenic, with low reactogenicity, in all age groups and appears suitable for targeted and/or repeat Tdap boosters in children, adolescents, adults, and elderly individuals as part of immunization strategies that may prove beneficial in further limiting the burden of pertussis 6, 7.