When majority of the population develop immunity to a disease either naturally or through immunization by vaccination and it indirectly provides protection by inhibiting spread to susceptible individuals in the community, it is known as “herd immunity”, “herd protection” or “community immunity”. Polio is a prime example, which was once very prevalent in our country but now occurs very rarely because the vaccine helped establish herd immunity. Initially, in response to Covid-19, UK and Sweden were the only two countries...