Illustrated by Kristin Brenemen. SOURCE: CDC

A measles outbreak originating at Disneyland in California has infected more than 120 people across 14 states since December. California allows vaccine exemptions to grant students who are not vaccinated entrance to public school for medical, religious and philosophical reasons, along with 19 other states.

The map to the left shows reported data from the Centers for Disease Control and Prevention website regarding the outbreak from Dec. 28 to Feb. 6 as well as the allowed exemptions in each state.

By Feb. 6, 114 Measles infections were linked to the outbreak occurring at Disneyland. The number of cases by state are as follows: California (99), Arizona (7), Utah (3), Washington (2), Oregon (1), Colorado (1), and Nebraska (1).

The CDC reports that the outbreak likely started from a traveler who had been infected with measles overseas, but they have not identified a source.

Twenty states have vaccine exemptions for philosophical and religious reasons, in addition to medical reasons. Included in those are California, Minnesota and Louisiana, whose laws do not explicitly recognize religion as a reason for vaccine exemption, although the philosophical exemption can be used to encompass religious beliefs.

There are 28 states that allow vaccine exemptions for religious reasons, in addition to medical reasons. Only two states—Mississippi and West Virginia—do not allow vaccine exemptions for either religious or philosophical reasons, only medical.

The Mississippi Supreme Court found in 1979 that parents could not demand their unvaccinated child be admitted into public school due to their religion, effectively outlawing a religious vaccine exemption in the state.

Groups like the Mississippi Parents for Vaccine Rights are lobbying for more lenient vaccination laws in the state.