• Posted July 25, 2023

1 in 6 Kids Haven't Gotten All of Their Vaccines. Why?

Most early childhood vaccines require three or four doses for best protection, but more than 1 in 6 toddlers aren't getting them all, leaving them vulnerable to potentially deadly infections, a new study finds.

There are many reasons that kids aren't completing their vaccine series, according to researchers. Some families may have moved across state lines and others may lack health insurance, they say.

For the study, a team led by the University of Montana's Sarah Michels examined immunization rates for the series of seven vaccines that protects against diphtheria, pertussis (whooping cough), tetanus, polio, measles, mumps, rubella, hepatitis b, Haemophilus influenzae type b, varicella and pneumococcal infections. The data included more than 16,300 toddlers nationwide who were between 19 and 35 months of age in 2019.

Close to 73% completed the combined seven-vaccine series, the data showed. Just shy of 10% did not initiate one vaccine series or more. And 17.2% began but did not complete one or more multidose vaccine series, the new study showed.

Just over 8% of children needed only one additional vaccine dose to complete the series. And, 1.1% of children were completely unvaccinated, the study found.

Black children were less likely to have completed their vaccination series. What's more, children living in lower-income households and rented homes were up to 30% more likely to not finish the vaccine series, the study showed.

“Increased focus on strategies to encourage multidose series completion is needed to optimize protection from preventable diseases and achieve vaccination coverage goals,” the researchers concluded.

The findings were published July 25 in the journal Pediatrics.

Outside experts stress the importance of fully vaccinating kids against these preventable and often life-threatening illnesses.

“Completing the vaccine series on time is very important,” said Dr. Robert Clarick, an attending physician at Children's Hospital at Montefiore in Bronx, N.Y.

“In communities across the country, we have seen multiple outbreaks of vaccine-preventable diseases such as measles and pertussis when vaccination levels have fallen,” he added.

The impact of moving across state lines and the lack of health insurance cited in the study particularly ring true, Clarick said. Vaccine registries with electronically shared information are extremely helpful with new patients, he said, adding that records from other states are generally unavailable.

“Without full information, there can be hesitancy to give vaccines that perhaps were previously administered, or there may be delays while attempting to obtain records,” Clarick said. “Moves and lack of insurance also often go together, as families may have delays in obtaining coverage when they move, and lack of insurance coverage leads to fears of the potential cost of visits to the doctor.”

The vaccines and their administration are free through the Vaccines for Children program, he said, but parents don't always know this, and there may be other costs associated with a medical visit.

Clarick's advice?

“When families with young children move, we strongly recommend establishing care with a new provider quickly,” he said. “Before you move, particularly if it is to another state, try to make sure that you have an up-to-date copy of your child's vaccine record, and bring that record to your first appointment.”

The new findings also reflect the experience of Dr. Gabrina Dixon. She is the director of Advancing Diversity in Academic Pediatrics and a pediatric hospitalist at Children's National Hospital in Washington, D.C.

Many factors are at play, she said.

“One example is parental due to misinformation about vaccines,” Dixon said. “It is important to educate parents/caretakers about vaccines and how they prevent transmissible illnesses.”

A lack or lapse of insurance may also factor in, she added.

"Many insurances cover the cost of routine vaccinations so when there is a lack of insurance, families would have to pay out-of-pocket for vaccines,” Dixon said.

The importance of completing the routine vaccination series can't be overstated, she said.

“Due to vaccinations, we have been able to significantly reduce illnesses such as varicella and polio,” she said. “It is important for children to stay up to date on vaccines. as it can help prevent transmissible diseases such as pertussis in your child.”

More information

The U.S. Centers for Disease Control and Prevention has the full vaccine schedule for toddlers.

SOURCES: Robert Clarick, MD, attending physician, Children's Hospital at Montefiore, Bronx, N.Y.; Gabrina Dixon, MD, MEd, director, Advancing Diversity in Academic Pediatrics, pediatric hospitalist, Children's National Hospital, Washington, D.C; Pediatrics, July 25, 2023