American Board of Internal Medicine (ABIM) Certification Practice Exam

What is the main purpose of postexposure vaccination following smallpox exposure?

1. To prevent outbreaks in the community

2. To enhance the immune response to unrelated infections

3. To provide protection from the infection

4. To eliminate the need for quarantine

The correct answer is: To provide protection from the infection

The main purpose of postexposure vaccination following smallpox exposure is to provide protection from the infection. When an individual is exposed to the variola virus, which causes smallpox, timely vaccination can stimulate the immune system to develop a protective response before the virus can cause symptomatic disease. This is particularly crucial because smallpox has a relatively long incubation period, allowing for vaccination to induce immunity effectively. Smallpox vaccination, even after exposure, can significantly reduce the severity of the disease or prevent it altogether. The vaccine works by training the immune system to recognize and combat the variola virus rapidly. This approach is especially important in the context of potential bioterrorism and the goal of eradicating the disease. While preventing outbreaks in the community and eliminating the need for quarantine are important considerations in managing infectious diseases, the primary aim of postexposure vaccination is to confer immediate protective benefits to the individual who has been exposed. Enhancing the immune response to unrelated infections is not a primary goal, and postexposure vaccination for smallpox specifically targets the variola virus itself, making option C the most pertinent choice.