Herd immunity protects a whole community from disease by immunizing a critical mass of its populace. Vaccination protects more than just the vaccinated person. By breaking the chain of an infection's transmission, vaccination can also protect people who haven't been immunized.
Anti-vaxxers often don't seem to understand that their unvaccinated children are a risk to children too young to be vaccinated, to people with immune disorders, to people who can't be vaccinated for medical reasons, to people with transplants, and even to vaccinated children (no vaccine is 100% effective). Pinned by RtAVM https://www.facebook.com/RtAVM