Historically, which vaccine contains whole-cell pertussis and is used in many countries outside the United States?

Historically, which vaccine contains whole-cell pertussis and is used in many countries outside the United States?

• A. DTaP
• B. DTP
• C. Td
• D. Tdap

Answer: (B)

Vaccine formulations for pertussis include whole-cell and acellular versions. The one that contains whole-cell pertussis is the classic diphtheria-tetanus-pertussis combination given with the entire, inactivated Bordetella pertussis organism. This whole-cell formulation was used widely in many countries outside the United States because it provoked strong immune responses, though it came with more adverse reactions such as fever and injection-site effects. Over time, the United States moved to the acellular pertussis formulation (DTaP) for the primary series to reduce reactogenicity, and boosters like Tdap also use the acellular component. The other options do not include whole-cell pertussis: they either use acellular pertussis or omit pertussis altogether.

Vaccine formulations for pertussis include whole-cell and acellular versions. The one that contains whole-cell pertussis is the classic diphtheria-tetanus-pertussis combination given with the entire, inactivated Bordetella pertussis organism. This whole-cell formulation was used widely in many countries outside the United States because it provoked strong immune responses, though it came with more adverse reactions such as fever and injection-site effects. Over time, the United States moved to the acellular pertussis formulation (DTaP) for the primary series to reduce reactogenicity, and boosters like Tdap also use the acellular component. The other options do not include whole-cell pertussis: they either use acellular pertussis or omit pertussis altogether.