That, at least, is the conclusion of a new review of these sites, which appears in today's issue of the Journal of the American Medical Association. It says that they tug at the heartstrings by telling stories about, and posting pictures of, people who were supposedly harmed by vaccines, but offer little evidence to back up their claims.
Not surprisingly, the assertions have infuriated some in the "anti-vaccine" camp.
"This is not a study. It is an op-ed piece," says Barbara Loe Fisher, co-founder and president of the National Vaccine Information Center, which operates a Web site. "This article is a sophomoric attempt to label the vaccine-safety and informed-consent movement as 'anti-vaccine' in order to deflect attention from the very real gaps in scientific knowledge about the biological mechanisms of adverse responses to vaccination. After 20 years of trying to work within the system to make vaccines and vaccine policies safer, it is very annoying to be simplistically labeled 'anti-vaccine.'"
Dr. Robert M. Wolfe, lead author of the study and an assistant professor of family medicine at Northwestern University's Feinberg School of Medicine in Chicago, says he wanted to find out what motivated people to take this stance, especially in light of statistics indicating that a growing number of people are refusing vaccines for their children.
Although the majority of parents do support vaccines, a recent national survey found that 25 percent believe that vaccinations could weaken a child's immune systems, while 23 percent believe children get too many immunizations.
Wolfe also cited research saying that, in the last year, 92 percent of pediatricians reported at least one parental vaccine refusal, while 18 percent reported an increase in refusals. "Quite a few people are starting to notice this, and doctors are surprised," Wolfe says.
At the same time, studies show that about two-thirds of U.S. adults (137 million people) are now online and that 80 percent of all adults online use the Internet to look for health information. More than half of those who are wired believe that "almost all" or "most" of the health information they find on the Internet is credible.
"We wanted to at last make doctors aware of what was online and what people were talking about and thinking about," Wolfe says. "Perhaps doctors will go one step further."
Wolfe and his colleagues sifted through the Internet and ended up analyzing the content and design of 22 "anti-vaccination" Web sites.
Most of the concerns on these sites seemed to revolve around vaccine safety and effectiveness and mandated vaccinations as a violation of civil liberties. They espoused a preference for alternative medical practices, such as homeopathy.
All of the sites studied claimed that vaccines cause idiopathic illness, such as autism (idiopathic illnesses are those where the cause is unknown). A vast majority of sites (95 percent) said that vaccines erode immunity, an equal number said that adverse reactions to vaccines are underreported, and 91 percent said that vaccination policy is motivated by profit concerns.
Some 55 percent of the sites included personal accounts by parents who felt that their child had been killed or harmed by a vaccine. A proportion of these sites included photos. Sixty four percent of the sites surveyed included information on how to legally avoid vaccinations.
The article did not include a list of specific Web sites surveyed.
The gap between pro- and anti-vaccination camps could be partially a generational thing, says Wolfe, who remembers being lifted through a window into his Bronx apartment building so as to avoid passing by the door of an apartment where a child with polio lived.
"When you hear stories about kids who have polio and are paralyzed, it gives you a whole different perspective," he says.
Wolfe also believes there's a blame factor. "The real jet fuel is this rage of parents that feel that their kids were damaged and they need someone to blame," he says. "They can direct rage someplace and have a sense of meaning that they are crusading against this evil."
Not so, says the other side.
"These kinds of articles trying to shut down the dialogue will never outweigh the very real experiences of parents taking healthy babies into their doctors to be vaccinated and then watching their babies regress and become chronically ill," says Fisher, who has served on vaccine advisory committees for the Institute of Medicine and the Food and Drug Administration.
Both Wolfe and Fisher point out that some pro-vaccination groups are now using graphic pictures of children who were not vaccinated against polio or diphtheria to evoke the same emotional reaction.
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