THURSDAY, Oct. 12, 2017 (HealthDay News) -- Vaccination rates for American kindergarten students remain high -- about 94 percent of students were immunized against major childhood diseases in the 2016-2017 school year, U.S. health officials report.
Still, roughly 6 percent of kindergartners had not had two doses of measles, mumps and rubella (MMR) vaccine or two doses of varicella vaccine, which protects against chicken pox, the U.S. Centers for Disease Control and Prevention said.
A similar percentage had not had the required number of doses of diphtheria, tetanus and acellular pertussis vaccine (DTaP), the annual assessment of public and private school students showed.
Among those not vaccinated, about 2 percent had exemptions for medical, personal or other reasons. Another 2 percent were enrolled provisionally while waiting for the shots, researchers noted.
One pediatrician who reviewed the findings said they serve as a reminder to a minority of vaccine naysayers that the shots save lives.
Illnesses like measles, diphtheria and tetanus are "terrible diseases that were common at one time in the United States, but have declined because of protective immunizations," said Dr. Sophia Jan. She directs pediatrics at Cohen Children's Medical Center in New Hyde Park, N.Y.
And while overall U.S. vaccination rates remain high, there are areas of the country with higher percentages of parents who don't immunize their kids, Jan noted. And that affects everyone.
"If your child is in a community where many children are not immunized, and your child is immunocompromised or cannot receive vaccines, then he or she is at greater risk of contracting these diseases," Jan pointed out.
The CDC researchers said that "kindergarten vaccination requirements provide an opportunity for children to be fully vaccinated with recommended age-appropriate vaccines and to catch up on any missed early childhood vaccinations."
Tracking vaccination rates is important because compliance can vary between states or even within states, they noted.
"School assessment allows immunization programs to focus on schools with lower vaccination coverage and higher exemption levels," wrote the research team led by Ranee Seither, of the CDC's National Center for Immunization and Respiratory Diseases.
Follow-up then helps ensure that kindergartners are protected from vaccine-preventable diseases, they explained.
Among the other findings in the report:
- Exemption rates of 4 percent or more were reported in nine states. These states were Alaska, Arizona, Idaho, Maine, Nevada, Oregon, Utah, Washington state and Wisconsin.
- Maryland had nearly 100 percent coverage for the DTaP vaccine. Mississippi had the top rates of MMR and varicella vaccination (over 99 percent for both).
- California, New York, North Dakota and Tennessee reported increases in coverage of more than 1.5 percentage points for all reported vaccines from the 2016-2017 school year.
- Four states have reported coverage below 90 percent for at least one vaccine for at least six straight years. The researchers didn't name these four states.
The study included vaccination data for almost 4 million kindergartners. The national data was gathered during the 2016-2017 school year. Several states also provided vaccination information on their home-schooled students.
The findings were in the CDC's Oct. 12 Morbidity and Mortality Weekly Report.
The American Academy of Family Physicians explains why childhood vaccines are needed.