The world is struggling to find the quickest way to end the coronavirus pandemic. Herd immunity is one method that has been suggested by some. The concept is simple enough and involves allowing many people to become infected and also vaccinating people. As more people become infected and vaccinated, a larger portion of the population will have the antibodies to prevent infection/reinfection. That means fewer people will carry the coronavirus and transmit it to other people. The population will therefore be protected as the majority of people become immune to the coronavirus.
Herd immunity depends on voluntary infections. As younger people have a better chance of surviving COVID-19 infections, some proponents of herd immunity have suggested that they volunteer to get infected and build immunities in their bodies. Unfortunately however, the process of undertaking herd immunity will come at the expense of many more deaths. Additionally people will not stay immune forever. Some evidence suggests that people who have been infected before can get reinfected with COVID-19. The evidence also shows the coronavirus is mutating, which makes it even more dangerous to people.
Once the vaccines are available, everyone should get vaccinated; this will be the most effective way to ensure herd immunity works well.