Which of the following is an example of a live vaccine?

Which of the following is an example of a live vaccine?

• A. DTap vaccine
• B. MMR vaccine
• C. Influenza inactivated vaccine
• D. Hepatitis B vaccine

Answer: (B)

Live vaccines contain weakened forms of the pathogen that can still replicate in the body, which helps trigger a strong and durable immune response. The MMR vaccine is a live attenuated vaccine because it uses weakened measles, mumps, and rubella viruses that replicate briefly in the vaccinated person, promoting robust humoral and cellular immunity with typically durable protection after a couple of doses. In contrast, the DTaP vaccine is not live; it uses toxoids and purified components. The influenza vaccine listed is the inactivated form, which cannot replicate. The hepatitis B vaccine is a recombinant subunit vaccine containing only a surface antigen, not a live organism.

Live vaccines contain weakened forms of the pathogen that can still replicate in the body, which helps trigger a strong and durable immune response. The MMR vaccine is a live attenuated vaccine because it uses weakened measles, mumps, and rubella viruses that replicate briefly in the vaccinated person, promoting robust humoral and cellular immunity with typically durable protection after a couple of doses. In contrast, the DTaP vaccine is not live; it uses toxoids and purified components. The influenza vaccine listed is the inactivated form, which cannot replicate. The hepatitis B vaccine is a recombinant subunit vaccine containing only a surface antigen, not a live organism.