Common alternative vaccine schedules mean underimmunization of children

More than 1 in 8 parents have adopted an alternative vaccination schedule for their children, according to a recent University of Michigan survey, and almost twice that number do not believe that the recommended schedule from the Centers for Disease Control and Prevention (CDC) is the best one to follow.

For pediatricians, the numbers show the urgent need for parental education to address concerns about safety and the need for vaccinations. Of the 13% of parents who use an alternative schedule, 30% had initially followed the recommended schedule. More than 60% adopted an alternative schedule because it “seemed safer,” and 76% did so to avoid “vaccines that aren’t really necessary.”

Many parents currently following recommendations share these concerns. The survey indicates that 28% of parents who currently bring children in on time for immunizations may be “at risk” for adopting an alternative schedule because they believe that delaying vaccine doses is associated with fewer vaccination adverse effects, and 22% disagree or strongly disagree that the recommended schedule is the best one to follow. Almost 30% agreed that delaying or skipping vaccinations enables a parent to avoid exposing their child to unnecessary vaccines.

Researchers noted that the use of alternative vaccination schedules leads to underimmunization of children and has been shown to increase significantly the risk of contracting and spreading vaccine-preventable diseases.

A child who has skipped 1 or more vaccines has 22 times the risk of contracting measles and 6 times the risk of contracting pertussis compared with fully immunized peers. In addition, the risk of pertussis infection doubles in fully immunized children with each 1% increase in the proportion of school-aged children who are underimmunized. “Not following the recommended schedule leaves kids at risk for these diseases unnecessarily,” says lead researcher Amanda Dempsey, MD, PhD, MPH.

Researchers used KnowledgePanel, an opinion research service, to conduct a randomized national survey of 771 parents of children aged between 6 months and 6 years, of whom 95% reported having a regular health care provider. Only 8% of parents needed to change doctors to follow an alternative schedule; 30% said their pediatrician was “hesitant to go along” with their desired changes, but 40% reported that their doctor “seemed supportive” of the alternative.

The most commonly refused vaccines were H1N1 (86%) and seasonal influenza (76%). Measles-mumps-rubella (MMR) and varicella were the most commonly delayed at 25% and 46%, respectively. Parents using an alternate schedule frequently extended multiple doses over a longer-than-recommended period, most commonly lengthening the time between doses for MMR (45%) and diphtheria-tetanus-acellular pertussis (43%). Just 2% said that they declined all vaccinations for their children.

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