In this Sept. 29, 2011 photo, Kandace O'Neill poses with her 7-month-old daughter, in Lakeville, Minn. O'Neill's views on child vaccinations are shared by many parents who don't follow federal vaccine advice. Her 5-year-old son has had no vaccinations since he turned 1 and the baby girl has received none of the recommended shots.

CHICAGO — By age 6, children should have vaccinations against 14 diseases, in at least two dozen separate doses, the U.S. government advises. More than 1 in 10 parents reject that, refusing some shots or delaying others mainly because of safety concerns, a national survey found.

Worries about vaccine safety were common even among parents whose kids were fully vaccinated: 1 in 5 among that group said they think delaying shots is safer than the recommended schedule. The results suggest that more than 2 million infants and young children may not be fully protected against preventable diseases, including some that can be deadly or disabling.

The nationally representative online survey of roughly 750 parents of children age 6 and younger was done last year and results were released online Monday in the journal Pediatrics. They are in line with a larger federal survey released last month, showing that at least 1 in 10 toddlers and preschoolers lagged on vaccines that included chickenpox and the measles-mumps-rubella combination shots. That survey, also for 2010, included more than 17,000 households.

The Pediatrics survey follows other recent news raising concerns among infectious disease specialists, including a study showing the whooping cough vaccine seems to lose much of its effectiveness after just three years — faster than doctors have thought — perhaps contributing to recent major outbreaks, most notably in California. Also, data reported in September shows that a record number of kindergartners’ parents in California last year used a personal belief exemption to avoid vaccination requirements.

Kandace O’Neill is a Lakeville, Minn., mom whose views are shared by many parents who don’t follow federal vaccine advice. Her 5-year-old son has had no vaccinations since he turned 1, and her 7-month-old daughter has received none of the recommended shots.

“I have to make sure that my child is healthy, and I do not want to put medications in my child that I think are going to harm them,” said O’Neill.

O’Neill said she’s not an extreme anti-vaccine zealot. She just thinks that parents should make medical decisions for their children.

Study author Dr. Amanda Dempsey, a pediatrician and researcher at the University of Michigan, said vaccine skepticism is fueled by erroneous information online and media reports that sensationalize misconceptions.

These include the persistent belief among some parents about an autism-vaccine link despite scientific evidence to the contrary and the debunking of one of the most publicized studies that first fueled vaccine fears years ago.

Some parents also dismiss the severity of vaccine-preventable diseases because they’ve never seen a child seriously ill with those illnesses.

But vaccine-preventable diseases including flu and whooping cough can be deadly, especially in infants, said Dr. Buddy Creech of Vanderbilt University.