What is the historical significance of Dr. Jonas Salk and Dr. Albert Sabin in poliovirus vaccination?

• A. Sabin developed IPV; Salk developed OPV
• B. Both developed IPV
• C. Neither developed vaccines
• D. Salk developed IPV; Sabin developed OPV

Answer: (D)

Two landmark vaccines changed how polio is controlled: Jonas Salk developed the injectable inactivated poliovirus vaccine, and Albert Sabin developed the oral live attenuated poliovirus vaccine. The significance is that Salk’s vaccine uses killed virus given by injection to induce systemic immunity without any live virus in the body, making it very safe in terms of not causing polio. Sabin’s vaccine uses a weakened live virus given as drops in the mouth, which not only protects the person but also helps interrupt transmission by boosting immunity in the gut, the primary site of poliovirus replication.

Together, these vaccines dramatically reduced polio worldwide and enabled mass vaccination campaigns. OPV’s ease of administration and strong community protection accelerated declines in cases, while IPV offered a safer injectable option that avoided any risk of vaccine-derived poliovirus. The trade-offs are important: OPV can rarely revert to a form that causes paralysis, whereas IPV does not carry that risk but requires injections and mainly provides systemic rather than intestinal immunity. Other choices misstate who developed which vaccine, whereas the pairing of Salk with IPV and Sabin with OPV accurately reflects their historical contributions.