The first national survey of attitudes toward autism reveals that a small but significant percentage of people still believe the disease is caused by childhood vaccines. The survey of 1000 randomly selected adults was conducted for the Florida Institute of Technology.
Nearly one in four (24 percent) said that because vaccines may cause autism it was safer not to have children vaccinated at all. Another 19 percent were not sure. This at a time when the Centers for Disease Control reports that autism affects one in 150 children born in the United States.
Scientists say there is no evidence linking vaccines and autism, but the lingering fear is leading to fewer parents having their children vaccinated and a growing number of measles infections. The New York Times reported in August that measles cases in the first seven months of 2008 grew at the fastest rate in more than a decade and cases in Britain, Switzerland, Israel and Italy are said to be soaring.
The public's concern over vaccines stems from a controversial 1998 British study linking autism and the MMR vaccine, which at the time contained the mercury-based preservative thimerosal. The study was later retracted by most of its authors and thimerosal was removed from all childhood vaccines in 2001, but responses to the just-completed survey show the public is still confused.
Florida Institute of Technology commissioned the survey, which asked specifically about the link between the preservative and autism. Nineteen percent of the respondents agreed with the statement "Autism is caused by a preservative once found in childhood vaccines." An additional 43 percent were not sure, meaning fewer than half (38 percent) of the respondents believe no link exists between the vaccine and autism.
Part of the confusion may stem from the fact that the cause of autism is unknown, according to Florida Tech Assistant Professor of Psychology Celeste Harvey. More than three in four respondents (76 percent) to the national survey agree with the statement: "At this time, scientists don't know exactly what causes autism."
"Fear of the unknown, coupled with anxiety over the growing incidence of the disease, may be leading people to draw their own conclusions," said Harvey.
The first national survey of the public's knowledge and understanding of Autism was conducted for the School of Psychology at Florida Institute of Technology, Melbourne, Fla. The survey includes responses from 1000 men and women, 21 years old or older, randomly selected from throughout the nation. The poll has a plus or minus 3.1 percent confidence interval at a 95 percent level of confidence. The telephone interviews were conducted between August 1 and August 29 by GDA Education Research, Mount Pleasant, S.C.
In addition to asking whether a link exists between autism and childhood vaccines, the survey explored people's knowledge of the disease, their exposure to people with autism and their support for early intervention programs. More results of the survey will be released at the Institute's 2008 Autism Conference on Friday, Oct. 3, in Melbourne. More information can be found at research.fit.edu/autismconference
Source: Florida Institute of Technology
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