Which outcome best reflects the purpose of rapid response vaccination in outbreaks?

• A. To delay immunization to observe outbreak dynamics
• B. To vaccinate only after the outbreak ends
• C. To rapidly elevate population immunity and interrupt transmission
• D. To reduce vaccination coverage to save costs

Answer: (C)

Rapid response vaccination is about quickly boosting immunity in the population to stop transmission during an outbreak. By rapidly increasing the number of protected individuals, the virus has fewer susceptible hosts to infect, which lowers the effective reproduction number and interrupts spread while the outbreak is still unfolding. In poliovirus outbreaks, this approach aims to rapidly raise population immunity through mass campaigns and targeted vaccination of contacts and at-risk groups, helping to seal transmission chains and protect those not yet vaccinated. The goal is not to wait until the outbreak ends or to cut vaccination coverage for cost savings; delaying vaccination lets more people become infected and ongoing transmission continues, while reducing coverage undermines control efforts and can prolong the outbreak.