The polio vaccine developed by Jonas Salk is which type?

The polio vaccine developed by Jonas Salk is which type?

• A. Live vaccine
• B. Attenuated vaccine
• C. Subunit vaccine
• D. Inactivated vaccine

Answer: (D)

The main idea here is distinguishing vaccines by how the pathogen is prepared. Salk’s polio vaccine uses a virus that has been killed so it can no longer replicate, which makes it an inactivated vaccine. Killing the virus preserves the parts the immune system recognizes, so the body makes neutralizing antibodies without any real infection. Because nothing in the vaccine replicates, protection relies on administering multiple doses to boost immunity, and it remains safe for people with weakened immune systems. This differs from live attenuated vaccines, which use a weakened form that can replicate and often provide broader, longer-lasting immunity but carry a tiny risk of causing disease. Subunit vaccines use only specific pieces of the pathogen, not the whole organism, which is not what Salk used.

The main idea here is distinguishing vaccines by how the pathogen is prepared. Salk’s polio vaccine uses a virus that has been killed so it can no longer replicate, which makes it an inactivated vaccine. Killing the virus preserves the parts the immune system recognizes, so the body makes neutralizing antibodies without any real infection. Because nothing in the vaccine replicates, protection relies on administering multiple doses to boost immunity, and it remains safe for people with weakened immune systems. This differs from live attenuated vaccines, which use a weakened form that can replicate and often provide broader, longer-lasting immunity but carry a tiny risk of causing disease. Subunit vaccines use only specific pieces of the pathogen, not the whole organism, which is not what Salk used.