SOMERSET -—In eight states now, more than 1 in 20 public school kindergartners aren't getting all the vaccines required for attendance, an Associated Press analysis found.
Alaska had the highest exemption rate in 2010-11, at nearly 9 percent. Colorado's rate was 7 percent, Minnesota 6.5 percent, Vermont and Washington 6 percent, Oregon, Michigan and Illinois were close behind. Pennsylvania had a high vaccination rate with only 3 percent exempted.
Rules for exemptions vary by state and can include medical, religious and philosophical reasons. Some parents are skeptical that vaccines are essential. Others fear vaccines carry their own risks. By the time most children are 6, they will have been given about two dozen shots.
Dr. Ajay Singh, a Somerset pediatrician, said Somerset County's rate is probably in line with the rest of the state.
"People here by and large understand the importance of immunization," he said in a telephone interview. "Most Amish also vaccinate their children. Fifteen years ago, they did not believe in it. Then there was a big outbreak of polio that changed their minds."
There were two polio outbreaks among the Amish in recent years. One was in 2005 that infected four children in Minnesota. The other was in several states in 1979. Polio causes paralysis in about one in every 200 infections.
There was an outbreak of measles in October that affected over 200 children in Minnesota and in Utah. Singh didn't see any patients with measles, but has seen a few cases of chicken pox. Last year a fair amount of his patients had pertussis, commonly called whooping cough. The California Department of Public Health reported last year that California had its worse pertussis outbreak in 50 years, with over 900 cases including five deaths. What was frightening about the pertussis outbreak was that it was found in both children and adults who had been immunized, Singh said. Their antibodies were low and they needed booster shots.
Concerns about a link between vaccines and autism were first raised more than a decade ago by British physician Andrew Wakefield. He claimed that the preservative thimerosal, which contains mercury, caused autism. Autism is a developmental disorder. His report has since been discredited and was retracted in 2010 by the journal that published it. A 2010 study released by the Immunization Safety Office at the Centers for Disease Control and Prevention adds to the evidence that thimerosal does not increase children's risk of autism. Vaccines no longer contain thimerosal.
"We stress that the information comes from a trusted source," Singh said. "We reassure parents that vaccines are safe. The occasional side effects shouldn't deter them. They forget that these diseases can be severe. Young parents now have no idea how parents used to fear polio. Vaccines are very safe and are the only thing for the prevention of childhood diseases which can be serious, even lethal. The risk of diseases is far greater than the risk of side effects."