Parents Who Don't Follow Recommended Vaccine Schedule Increase Risk of Preventable Outbreaks

A national survey of parents of young children found more than 1 in 10 use an alternative vaccination schedule, and a large proportion of parents using the recommended schedule seem to be "at risk" for switching to an alternative schedule.

"Small decreases in vaccine coverage are known to lead to dramatic increases in the risk of vaccine preventable disease outbreaks," says Amanda Dempsey, MD, PhD, MPH, assistant professor in the department of pediatrics and communicable diseases and a member of the Child Health Evaluation and Research Unit at C.S. Mott Childrens Hospital. "Not following the recommended schedule leaves kids at risk for these diseases unnecessarily."

Following a vaccination schedule that deviates from those recommended by recognized groups such as the Centers for Disease Control and Prevention and the American Academy of Pediatrics leads to under-immunization. Under-immunization has been shown to significantly increase the risk of contracting and spreading vaccine preventable diseases like measles and whooping cough," Dempsey adds.

This research shows that the problem of under-immunization is likely to continue to worsen in the future given that many parents have attitudes that indicate they are not convinced about the safety of having their kids vaccinated at recommended times.

The study, "Alternative vaccination schedule preferences among parents of young children," was published online today ahead print in the journal Pediatrics. It involved a survey of 771 parents of children ages 6 months to 6 years.

Among this group, surveyed in May 2010, 13 percent reported deviating from the recommendations, though only 2 percent refused all vaccines.

Most of the parents using an alternative schedule said they themselves (41 percent) or a friend (15 percent) developed the schedule, and 8 percent reported using a well-known alternative schedule such as the one developed by Dr. Bob Sears of

Using an alternative vaccine schedule was strongly associated with not having a regular healthcare provider for the child. The vaccines most commonly delayed were the measles-mumps-rubella (45 percent) and diphtheria-tetanus-acellular pertussis (43 percent) vaccines.

A large minority (30 percent) of parents using an alternative schedule said they had initially followed the recommended vaccination schedule; most said they switched because it "seemed safer."

Additionally, 1 in 4 parents who followed the regular vaccination schedule thought that delaying vaccination was still safer. Study authors conclude this highlights the need to develop strategies to prevent the spread of attitudes and beliefs that counter vaccination.

"More resources need to be devoted to finding ways to successfully change where attitudes are going," Dempsey says. "Clearly this problem is not going to go away, and our data suggests it will actually get worse over time."

Doctors are already working hard to stress the importance of timely vaccinations, but many people have their minds made up by the time they see the doctor. The Centers for Disease Control and Prevention, the American Academy of Pediatrics and many other medically-oriented websites have a wealth of information about vaccines that parents can easily access.