This is part of The Vaccine Divide, an updated data investigation into America potentially losing its measles-free status as the deadly virus roars back and childhood vaccine defenses continue to crack and crumble.
As vaccination rates among children go down, the risk of getting sick from a vaccine-preventable illness such as measles goes up.
Use these maps to see the childhood vaccination rates for your community.
The measles-mumps-rubella vaccine is highly effective in preventing illness in children and adults. To control the spread of measles in a community, a vaccination rate of 95% or higher is needed. A growing number of counties across the country are seeing the level of vaccination among children entering kindergarten drop below that protective threshold.
The number of children entering kindergarten whose parents or caregivers opt them out of vaccines has been steadily climbing in the U.S. for at least a decade. States differ in their requirements for vaccine exemptions, which can be for medical, religious or personal beliefs.