Herd Immunity: Herd immunity, also known as community immunity, is a type of indirect protection from infectious disease that occurs when a certain percentage of the population has developed an immunity to an infection, thus providing a degree of protection for individuals who are not immune. The exact proportion of a population that needs to be immune is called the herd immunity threshold, which varies from disease to disease. For example, measles require 92-95% of the population to be protected and influenza has a herd immunity threshold of about 33-44%. In a population with a substantial number of immune individuals, propagation of infections are likely to be stopped or slowed. The greater the percentage of individuals with immunity within a population, the smaller the probability that those who are not immune will come into contact with an infectious individual. Since some individuals cannot become immune due to medical complications like having a compromised immune system, herd immunity is an important method of protection. Below is a simulation of herd immunity to demonstrate the concept at hand. Source: theotheredmund #science #biology #immunology #InfectiousDiseases #GIF