Atlantic Health Partners

Herd Immunity: Protecting Individuals and Communities at Large

As more people become vaccinated against COVID-19, the term “herd immunity” has emerged as a popular buzzword. The earliest use of the term can be traced back to a study examining bacterial transmission between a “herd” of mice in 1923. It was discovered that herd immunity occurs when a significant portion of a population becomes immune to an infectious disease. The principle of herd immunity has been critical to eradicating certain diseases. For example, when the World Health Organization launched its campaign to eradicate smallpox in the 1960s, widespread vaccination was key to halting the spread of the disease.  

By preventing the spread of disease within communities and protecting those who cannot be vaccinated, herd immunity disrupts chains of infection. Below we review what herd immunity is, how it is developed, and why it's important.

Sign up to the
WAFP Email List