Vaccination Exemptions in the USA

The United States Centers for Disease Control (CDC) publishes a Morbidity and Mortality Weekly Report, and in it they track the vaccination rates in different states for children enrolled in kindergarten, and an interesting table is the report on the rate of exemptions from vaccinations, as well as the reason behind it. Granted, different states have varying laws with regards to vaccination requirements, and some allow separation of the exception reasons between medical, religious and other philosophical reasons, which makes getting consistent data problematic. But we do have good data for the 2015–2016 enrollment, and the 2016–2017 enrollment.

The reports themselves are straight tables, but data visualization helps in teasing out the meaning there.

Summarizing the CDC reports between 2015-2016 and 2016-2017 school years for the rate of vaccine exemptions among kindergarten students, divided by state. A number of states are excluded. Blue dots are for the earlier year, red dots for the data a year later. Note that for herd immunity, the general consensus is about 95% of the population should be vaccinated. The Y-axis displays the ratio between medical and non medical reasons given for the exemption. Note that with the exception of DC, all states have ratios below 1, which means that more people are seeking exemptions for religious or philosophical reasons than for medical ones. 

This data is dense, but highlights some problematic states, like Oregon, which has an unusually high rate of vaccine exemptions, and most of them for non medical reasons. Let’s look at the trend from year to year.

Change year
The arrows point in the direction which portend better public health trends: a drop in the rate of exemptions, and an increase in ratio of medical to non-medical reasons. California and Vermont seem to be on the right track, but most of the country is actually inching in the wrong direction, with Nevada and Wisconsin leading the way. 

Sadly, the antivaccinationist movement seems to be permeating the mindshare, just by manipulating doubt and exploiting parental concern. Non medical exemptions are a key to this degradation of our public health system.

Leave a Reply