Interventions to Protect Kids & Stop the Spread of Disease

The Social Contract & Herd Immunity

At the core – vaccines are really about community protection.  Our public health system depends on a solid network of providers that are available to vaccinate kids for all the nasty infectious diseases that have plagued humanity for millenia.  Vaccinating yourself and your kids is more about community protection than personal protection. It’s a social contract that we have with each other to keep all of us healthy.

We need just about everybody to participate in our shared social contract to vaccinate in order to get the herd immunity.  When communities have herd immunity, those who can’t be vaccinated and folks with weakened immune systems will still be protected because the viruses can’t circulate.  Measles needs a 95% community vaccination rate to achieve herd immunity.


School Enrollment Requirements & Exemptions

To achieve herd immunity and prevent the spread of measles and other communicable diseases, every state including Arizona requires kids in public school to be vaccinated against a series of diseases, including measles.

All states allow an exemption from the required vaccines when it’s medically necessary.  Seventeen states (including Arizona) allow parents to exempt their kids from the requirements because of personal or philosophical beliefs (called personal belief exemptions).  BTW: HB 2162 would change that by removing Arizona’s personal belief exemption (it hasn’t been scheduled for a hearing).  States with a personal exemption option usually have lower vaccination rates than states without that option.

States also have authority to exclude kids that are unvaccinated from school during a vaccine preventable disease outbreak. In Arizona, ARS § 15-873(C) states that students “… who lack documentary proof of immunization shall not attend school during outbreak periods of communicable immunization-preventable diseases”.  The decision to exclude kids during an outbreak rests with the directors of the county health departments and school administrators and is prescribed in Arizona’s Communicable Disease Rules.


Immunization Rates Among AZ Schools

Arizona has many pockets in which our vaccination rates are below 95%, mostly in high income areas and among certain charter schools. One of our best sources of vaccine coverage data comes from schools and childcare centers- which are required to report their vaccination coverage and exemption rates for 19-35 month old’s, kindergartners, and 6th graders.

Public health agencies aren’t the only group of folks interested in school exemption rates. Many parents are interested in finding out whether their child’s school is has a high vaccination rate.  For the last several years, the ADHS has been posting the vaccination rates of schools across the state.

Last year exemption rates increased across all age categories. Exemptions rose from 3.9% to 4.3% for child care, from 4.9% to 5.4% for kindergarten and from 5.1% to 5.4% for 6th grade.  As is always the case, exemption rates were much higher in charter schools. Data for exemption rates and vaccine coverage rates by county and school are available on the ADHS website.  Note: updated exemption rates will be available in a couple of months.


Educating Parents

Arizona’s public health system has been doing some creative work to improve our immunization rates. One is an innovative on-line immunization education course that’s designed to serve as part of a potential new personal exemption process.  

Last year a pilot project was conducted recently at a dozen or so schools in Maricopa County to learn how to best implement an immunization education module, get feedback from school staff, and identify whether parents learned new information about vaccines using a pre-and post-knowledge assessment survey.

A new more robust pilot is planned for the 2019-2020 school year. The county health departments and the ADHS are partnering in the project.  At participating schools (hopefully as many as 125 schools), parents who want to exempt their kids from the school enrollment vaccination requirements will be asked to complete the Immunization Education Course first.  Upon completion, they’ll be able to download their school’s exemption form.

The online course is designed only for the use of Personal Beliefs Exemptions in grades K-12 at pilot program schools. It doesn’t change the process to request and obtain a Medical Exemption form or the Religious Beliefs Exemption form.

Hopefully the project will demonstrate positive results and will include an academic partner so the eventual results can be published and other states can learn from this important work.

We don’t have much time, though.  Vaccination rates are already below herd immunity levels for measles in many parts of the state, and all it’ll take right now is a sentinel measles case in the right place at the right time and we’ll have a measles outbreak- maybe one as bad as the one happening right now in Washington state and across much of Western Europe.