Does your child’s school have herd immunity against measles? Concerned California parents can get more concrete about the risk of measles with NurtureList’s new MMR vaccination feature, which allows parents to easily search the vaccination rates of preschools (the feature is built using data from the California Department of Public Health). Use it to check how many children are enrolled and vaccinated at your child’s facility.
Measles is a highly contagious disease but one that is well controlled when communities achieve “herd immunity”. Depending on the source consulted, the threshold to achieve herd immunity is between 90 to 95% of community members vaccinated. Parents of infants younger than 12 months and immune-compromised children (neither group can receive the vaccination) should be especially concerned. These children rely on others’ (such as the older children in the facility) being immunized for protection.
Many parents ask why schools don’t simply refuse admission to non-vaccinated children. We spoke with a well known San Francisco preschool and learned that schools aren’t allow to discriminate against non-vaccinated children with a philosophical, religious, or medical exemption in the admissions process.
We recommend that parents look up their daycare or preschool’s immunization rate and ask the facility’s director for the latest numbers. Parents can also talk to their primary care doctor about the risks especially if their child is in a group that cannot be vaccinated.
A Note About The Data
The raw data can be found here. It is for children aged 2 years to 4 year 11 months enrolled at licensed California child care facilities, recorded during the annual fall assessment. Not all facilities participated, but nearly 90% did. Note also that the data lags a bit (the latest year of survey was 2014), so parents should still ask schools for up-to-date numbers. Data for home-based daycares (also known as family child cares) is not published, as is data for facilities enrolling less than 10 children, so parents of children enrolled in these facilities will have to ask them directly.