What is herd immunity?

Herd immunity is the immunity developed by a majority of population against a desease over a period of time by way of vaccination or by exposing to the desease to develop immunity.The vaccinated or immunised population act as a buffer between the desease and the ones who are not vaccinated or who have not developed immunity.Herd immunity thus helps in checking further spread of the desease into the masses.

For herd immunity to be effective,in must infect or vaccinate at least 80 to 90% of population.Here more contagious the desease is the more stronger the herd immunity will be.However vaccination is the best and safe way to use herd immunity as a tool to contain a desease.

Herd immunity is being discussed now a days as a way forward to check the spread of the Covid-19 desease.how much successfull its going to be,only time will tell.