Oct. 21, 2011 -- Younger doctors may be slightly more skeptical about the safety and effectiveness of childhood vaccines than older doctors, a new study suggests.
Overall, support for childhood vaccination among doctors remains high, however, says Saad Omer, MBBS, PhD, MPH, of Emory University in Atlanta.
A second study shows more than one in five pediatricians in the Midwest have barred from their practice children of parents who refuse to have them vaccinated.
Each year, there are about 85,000 cases of disease that could be prevented by childhood vaccines, according to the researchers.
Both studies were presented at the annual meeting of the Infectious Diseases Society of America in Boston.
Safety and Effectiveness of Vaccines
Omer and colleagues surveyed 551 doctors. They found that more recent graduates were 15% less likely to believe that vaccines are effective, compared with older graduates.
Younger doctors were also more likely to believe that immunizations do more harm than good, Omer tells WebMD.
"We picked up subtle, but important differences," Omer says. But most doctors still strongly support vaccines.
As an example, 81% of the doctors, regardless of age, agreed that "vaccines are one of the safest forms of medicine ever developed," he says.
But each increase of five years in the year of graduation was associated with 20% lower likelihood a doctor believed that statement was true.
Eight percent of doctors overall agreed that "children get more immunizations than are good for them." But each increase of five years in the year of graduation was also associated with 20% increased odds a doctor believed that was true.
The findings are significant "because the most important source of information on vaccination is doctors," says Bruce Gellin, MD, director of the National Vaccine Program Office in Washington, D.C. He moderated a news briefing to discuss the findings.
The study wasn't designed to examine why age might affect beliefs on vaccination. Gellin's theory: Like young parents, young doctors are not familiar with some of the infectious diseases that have been virtually wiped out by immunization programs.
"As familiarity with a disease goes away, they're only hearing about the vaccine. That often isn't in sync with what the vaccines are designed to do," he says.
Omer stresses that parents shouldn't choose a pediatrician based on age. "Simply ask their beliefs on vaccination if you have concerns," he says.
Families 'Fired' for Refusing Vaccines
The second study involved 695 pediatricians from nine Midwestern states who filled out an online survey.
Overall, 21% of the doctors said they discharged families who continued to refuse all vaccines for their children.
There were huge variations by state, however. Minnesota doctors stopped treating such families less than 1% of the time. Iowa pediatricians discharged them 38% of the time, the survey showed.
"A proportion of doctors don't feel comfortable having unimmunized patients in their practice as they perceive them to be a risk to other patients in their waiting rooms," says researcher Christopher Harrison, MD, director of the infectious disease research laboratory at Children's Mercy Hospitals and Clinics in Kansas City, Mo.
Still, "firing families who refuse to vaccinate [may not be the solution] and raises the question of whether we need a new dialogue on how doctors should approach the situation," he tells WebMD.
Among other findings:
- The three vaccines that parents most often refuse or delay are MMR, HPV (human papillomavirus), and flu.
- The most common reasons parents give for refusing or delaying vaccination are fear of autism and concerns about too many shots and serious side effects.
These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.