The point at which a disease can no longer spread through a population because of the lack of nonimmune hosts.
The fact of a group of people being resistant to a specific disease, because many individuals in the group are immune to or immunised against the microorganism which causes it.
The ability of a community to resist epidemic disease. Herd immunity may develop naturally in a society as a result of widespread exposure to disease, or it may be stimulated artificially by mass vaccination programs.
Community immunity refers to the safeguarding of non-immune or unvaccinated individuals against diseases, which is granted by the collective immunity prevalent in a population as a result of extensive vaccination coverage.
Herd immunity is the protection of an entire community from an infectious disease due to immunity in the majority, but not all, of the population. This immunity can be naturally acquired or induced through immunization. For instance, if more than 85 per cent of a population is vaccinated against diphtheria, it can prevent the disease’s spread. This occurs because there are not enough susceptible individuals who could contract and transmit the disease to others. Consequently, even those without immunity receive a certain level of protection by being part of an immune population.