The refusal of many parents in the United Kingdom to have their children vaccinated in the fear that the shots could lead to autism or other problems may have put their children in danger of a different health threat -- that of infectious disease.
Despite mounting evidence against any link between vaccines and disorders such as autism and inflammatory bowel disease, researchers at the UCL Institute of Child Health and Great Ormond Street Hospital for Children in London found that many parents in the United Kingdom still refuse to have their children vaccinated for measles, mumps and rubella.
The researchers studied immunization data on 14,578 U.K. children born between 2000 and 2002.
What they found was that in 1995, 92 percent of U.K. children had received their MMR immunization on schedule, but this number dropped sharply to 79 percent in 2003 following a 1998 report in the journal Lancet that linked the vaccine to autism.
Despite the fact that this initial report suggesting a vaccine-autism link was subsequently withdrawn at the request of most of the study's authors, the fallout from this research remains.
The researchers noted that even though the number of children receiving the MMR vaccine is climbing again, currently only 88.6 percent of U.K. children had received their MMR immunizations. Doctors say that 95 percent of people must be vaccinated to fully protect a population.
The new study is currently published in the online version of the British Medical Journal.
More worrying, the researchers reported that the number of measles cases is on the rise. Rates of confirmed measles cases increased by more than 17 times -- from 56 cases to 971 cases -- from 1998 to 2007. One 13-year-old boy who was not vaccinated against MMR died last year after contracting measles.
According to Helen Bedford, lead study investigator and senior lecturer at the Center for Pediatric Epidemiology and Biostatistics, the reason for this fallout is due in great part to the wealth of inaccurate information circulating the Internet on the false vaccine-autism link.
"There is evidence that there is no link [between vaccines and autism], and there has never been any good research to show a link to autism and bowel disease," Bedford said. "But parents do get very concerned and want to protect their children, and sometimes they look to the Internet for information because it's readily available there.
"But if you do an ordinary Internet search for the MMR vaccine, you get a lot of Web sites that come up that have inaccurate and frightening information."
Rather than taking the advice of British health officials or the government to immunize all children at the age of 13 months for MMR and again right before the child starts school, researchers found that many parents have taken the issue into their own hands by immunizing their child for just one of the diseases instead of all three.
Researchers found that 5.2 percent of children received at least one of the single vaccines. Of the 634 children who received at least one of these vaccines, only about half -- 52 percent -- had received all three covered by the MMR vaccine.
According to Bert Jacobs, professor in the School of Life Sciences at Arizona State University, the startling correlation between the growing numbers of unvaccinated children and the increase in the number of measles outbreaks in the United Kingdom should be enough to convince parents worldwide of the usefulness of these vaccines.
"Perhaps the most troubling concept in the report is that some people think the risks of the vaccine are greater than the risks associated with not getting vaccinated," Jacobs said. "I think we have all become complacent and forgotten the devastation that these diseases can cause in a largely unvaccinated population.
"Perhaps the scariest part of the study is that with a rather modest decrease in vaccination rate there was a 17-fold increase in measles cases."
What Could Happen Here?
Although in the United States more than 95 percent of children receive their MMR vaccines before entering school, many experts believe that if similar vaccine fallout rates occur here the outcome could be catastrophic.
"Protection of communities against measles requires high coverage rates and uptake of vaccine by almost all children," said Dr. Neal Halsey, director of the Institute for Vaccine Safety at the Johns Hopkins Bloomberg School of Public Health in Baltimore. "We do see some limited outbreaks of measles [in the U.S.] due to people not immunizing their children. ... If more parents decline the vaccine, there is no question that we would see more and larger outbreaks, and we would see more hospitalized children and serious complications such as pneumonia and encephalitis."
Measles was actually declared eliminated from the United States in 2000, although it has remained endemic worldwide. In 2005, a 17-year-old unvaccinated girl contracted measles while traveling in Romania and brought the disease home with her to Indiana, creating the largest documented outbreak of measles in the United States since 1996.
From this one case, 34 more people contracted measles, 32 of whom were unvaccinated.
Just as with the Indiana outbreak, because a very high number of children receive the MMR vaccine in the United States, public health experts say that a measles outbreak here is more likely to be caused by someone importing the disease into our country from abroad.
Dr. Melinda Wharton, deputy director of the Center for Disease Control and Prevention's National Center for Immunizations and Respiratory Diseases, said that although many people in the United States have been immunized for the disease, we are not by any means safe from future outbreaks.
"The most important thing for people to understand is that measles is very contagious and, once introduced to group of people, the virus will find the people that are not protected," Wharton explained.
A recent measles outbreak in San Diego was caused by one single child who brought the disease back from Switzerland. From this one case alone, it was confirmed that 11 other people contracted the disease.
"So even if most people are protected by vaccine -- and we're fortunate in the U.S. that that's true -- but as long as there are people that are susceptible then there's a risk of it being transmitted to any other part of the world," Wharton said.
Due to the highly infectious nature of this disease, many experts say the only true way to protect your child from MMR is through making sure they get the required vaccinations.
"It is critical that parents vaccinate their children to protect that child, and to protect society as a whole," said Dr. James McAuley, director of the division of Pediatric Infectious Diseases at Rush Children's Hospital in Chicago. "There will be some children and adults, such as those with cancer who will not be fully protected by vaccines because their immune system is weakened. If the rest of us do our part, the resultant herd immunity will protect those individuals."