What is “herd immunity”?
Herd immunity occurs when a majority of the population (the “herd”) is vaccinated. When enough people are immune through vaccination, the disease is unable to spread. With nowhere to go, the virus dies out. It is then far less likely that anyone, immunized or not, will become infected with the virus. Usually, about 70%-90% of people must be vaccinated to reach herd immunity. Because these vaccines will take time to be distributed, we will need patience because it will take many months to reach this point with COVID-19.
To be clear: herd immunity is not the idea that a majority of people get sick with COVID-19 and recover. Herd immunity only applies to the COVID vaccine.