It’s no secret that many states including Arizona are struggling to maintain enough vaccination coverage to achieve “herd immunity”. Herd immunity simply means that you have enough vaccination coverage to protect the entire community – including people that for medical reasons can’t be vaccinated and folks who’ve been vaccinated but still may be susceptible (because vaccines aren’t 100% effective).
Requiring kids in public school to be vaccinated is one of the most important public policy tools to ensure herd immunity. Arizona does that through statutes labeled ARS-872 & ARS-873 – which require kids to be vaccinated if they attend public school (unless they have an exemption). In Arizona, there are medical, religious, and “personal” exemptions. The problem over the last few years is that more and more parents are exercising the personal exemption option.
Arizona’s immunizations rates continue to decline: 1) immunization rates have decreased across all age groups from 2012 to 2017; 2) personal exemption rates continue to be highest in charter schools, followed by private and public schools in 2017; and 3) overall personal exemption rates increased in the last year- going from 3.9% to 4.3% for pre-school; 4.9% to 5.4% for Kindergarten and 5.1% to 5.4% among 6th graders.
Of course- when looking toward interventions to stem the tide it’s important to look to the scientific literature to see what’s going on in other states. A very informative article about personal vaccine exemptions was published recently entitled The state of the antivaccine movement in the US: A focused examination of nonmedical exemptions in states and counties.
The researchers conducted a detailed analysis of personal exemptions within each of the 18 states that allow nonmedical exemptions to their school vaccine requirements. Here’s a map of which states allow non-medical school exemptions.
The researchers found that several counties, especially those with large metropolitan areas, are at high risk for vaccine-preventable pediatric infection epidemics. Since 2009, personal exemptions have risen in 12 of the 18 states that currently allow philosophical-belief exemptions. On average, states that allow non-medical exemptions have 2.5 times higher exemption rates.
The also dove into the data and found that there is a direct correlation between higher personal exemption rates and lower vaccination rates. That might be intuitive- but it’s important because it shows that personal exemption rates for school requirements is a good measure of real immunization rates.
The discussion portion of the article discusses the efficacy of interventions in various states, and basically found that more aggressive approaches – like eliminating personal exemptions entirely- are more effective at long term improvements in vaccination rates than softer approaches.
Definitely worth a read.