What does herd immunity protect?

Herd immunity protects those who are non-immune due to the overall population-level immunity that reduces the spread of infectious diseases. When a significant portion of a community becomes immune—either through vaccination or previous infections—it makes the transmission of the disease less likely. This decrease in spread helps shield individuals who cannot be vaccinated or who have weakened immune systems, effectively minimizing their risk of contracting the disease.

The concept relies on a collective effect, meaning that the immunity in the population creates a buffer around those who are susceptible, thereby preventing outbreaks and protecting vulnerable individuals. This is crucial in controlling diseases, especially those that can have severe consequences for certain groups.

Other choices focus on specific groups or individuals, which do not fully encapsulate the broader protective effect that herd immunity provides to the community as a whole. The essence of herd immunity is the indirect protection it affords to those who cannot protect themselves through vaccination.