Medical vaccine exemptions for children not always justified

Some children are receiving medical exemptions from kindergarten-entry immunization requirements for inappropriate reasons, according to a new study. That could make youths who are too young or too sick to be immunized more susceptible to potentially fatal vaccine-preventable diseases, including measles and pertussis.

“The appropriate use of medical exemptions is important to maintaining sufficient herd immunity,” said Saad B. Omer, PhD, MPH, senior investigator of the study, published online Aug. 29 in The Journal of Infectious Diseases.

Every state allows exemptions for children with medical contraindications that are verified by a physician. Health professionals issued 87,631 such exemptions from immunizations required for kindergarten between the 2004-05 academic year and the 2010-11 school year, the study said.

Fewer than 1% of kindergarteners received medical exemptions. Although the number is small, the research shows that states differ on the criteria they require for patients to opt out of vaccines for health reasons, said Omer, assistant professor in global health, epidemiology and pediatrics in the Hubert Dept. of Global Health at Emory University Rollins School of Public Health in Georgia.

Exemptions were more common in states with loose requirements for opting out of vaccines for health reasons than they were in states with stricter criteria, the study said. The study did not examine non-medical exemptions such as those granted for religious reasons.

Omer recommends states consider eliminating permanent medical exemptions and grant temporary ones instead. That change would encourage physicians to review patient immunization exemptions periodically and determine if they still are warranted.

It’s important that doctors be aware of the medical contraindications for the vaccines they administer, said Andrew T. Pavia, MD, chief of the division of pediatric infectious diseases at the University of Utah School of Medicine in Salt Lake City.

Doctors need to “realize that they’re not doing their patients a favor by granting them a medical exemption when they would have benefitted more by being vaccinated,” he said.

Falling short of vaccination goals

The Healthy People 2020 target is 95% or greater vaccination coverage among kindergartners for the following vaccines: diphtheria, tetanus toxoid, and acellular pertussis; hepatitis B; measles, mumps and rubella; poliovirus; and varicella.

During the 2011-12 academic year, median coverage for the MMR vaccine and varicella immunization fell short of the Healthy People goal, said a study in the Aug. 24 issue of the CDC’s Morbidity and Mortality Weekly Report.

For The Journal of Infectious Diseases study, researchers examined CDC data on state medical exemptions from vaccines required for kindergarten granted between 2004 and 2011. The study assessed the length of the medical exemption that could be granted (permanent, temporary or both) and the criteria required to grant the exemption.

Such criteria include a written physician statement; separate medical exemption form; health department approval; physician certified to practice in the state; annual approval of the exemption; and notarization of medical exemption forms.

States with one criterion were considered to have easy requirements, and having two criteria was said to be medium-level difficulty. States with at least three criteria were described as having difficult requirements.

Researchers found that the annual number of exemptions issued increased from 11,277 in 2004-05 to 13,952 in 2010-11.

In states with easy requirements, the rates of exemptions were more than six times higher compared with states that have difficult procedures, data show.

Difficult requirements were identified in three states: Arkansas, New Mexico and Wyoming.

The study “shows that medical exemptions aren’t being used well,” Dr. Pavia said. “It’s not ethical to give a medical exemption when the evidence doesn’t suggest it’s medically indicated.”