When a large proportion of a population is vaccinated, even unvaccinated individuals are protected because the pathogen cannot spread easily. This is called
- A. cross immunity
- B. passive immunity
- C. herd immunity
- D. autoimmunity
Explanation
Vaccinated people act as dead ends for transmission, shielding those too young or too ill to be vaccinated. Herd immunity is the public health reason vaccination coverage matters beyond the individual.