Which outcome best describes the goal of intensifying vaccination campaigns in an outbreak?

• A. Long-term herd immunity without timing constraints
• B. Immediate clinical cure for infected cases
• C. Rapidly raise immunity levels to interrupt transmission
• D. Delay vaccination to focus on surveillance

Answer: (C)

Intensifying vaccination during an outbreak focuses on quickly boosting the community’s protective immunity so transmission chains are stopped. Vaccines don’t cure people who are already infected; their power is to prevent disease and, when given rapidly to many people, reduce the number of susceptible individuals enough to push the effective reproduction number below 1. That drop means each case leads to less than one new case on average, so the outbreak begins to fade.

Timing matters here—waiting for long-term herd immunity doesn’t help the current flare-up, and delaying vaccination in favor of surveillance misses the chance to interrupt spread. By rapidly raising immunity levels, you increase the chance of interrupting transmission, protecting both the unvaccinated and those who haven’t yet developed protection.