Herd immunity against measles outbreaks

Seven of eight counties in the San Joaquin Valley have kindergarten measles vaccination rates of 95% or more, a level considered to provide "herd immunity" against the disease. Only Kern County falls short as it has for eight years.

Vaccination rates measure the percentage of kindergarten students who have had two doses of vaccine for measles, mumps and rubella (MMR) required for entry into school.
Chart: Tim Sheehan / Central Valley Journalism CollaborativeSource: California Department of Public Health