"If you go on blogs and the Web, there are a lot of anti-vaccine sites," said McCormick. "They continue to tout data that is showing an association, even if it is flawed. People don't know what is correct and [the belief in a link] is being continually reinvigorated."
The ingredient in flu vaccines that worries parent groups is thimerosal, a mercury-based preservative developed in the 1930s that helped prevent deep infections from immunization, according to McCormick.
By 2002, thimerosal was phased out of all childhood vaccines, except the one for flu, "as a precautionary measure," she said.
As the aunt of two autistic children, McCormick understands the frustration parents feel, but, she said, immunization is essential in combating infectious diseases, which are "only one plane ride away."
"Eli Stone" co-producer Marc Guggenheim says the producers don't oppose vaccinations. "Both my daughters have been vaccinated," he said.
"I think there's a huge difference between informing people about an issue and taking a stand and convincing people to take action," Guggenheim said.
Media critics say they, too, are wary of medical groups trying to steer fictional story lines.
"Anyone who uses the national storytelling medium of all time — television — should do it with a sense of responsibility and care," said Robert Thompson, professor of media and popular culture at Syracuse University. "But I don't want the [medical group] AMA telling people telling us what kind of stories to tell."
Thompson debunks doctors' arguments that viewers believe what they see on television. "If you watched soap operas you would believe that 50 percent of people get amnesia at one point," he said.
Mark Crispin Miller, professor of media, culture and communication at New York University, disagrees. Just because viewers know they are watching fiction doesn't mean that they don't get "confirmation for certain assumptions," he said.
"Regardless of the genre, television is a very topical medium," said Miller. Watching a recent episode of "Law and Order" that dealt with terrorism, "I certainly knew this was not a documentary, but I also found the drama to be credible and pertinent."
Propaganda, he reminds, "often comes disguised as narrative."
Meanwhile, Rachel Hotez spends 80 percent of her day out of school as her father seeks special services to help treat the complex symptoms of autism.
"Unlike an acute illness that resolves, this never goes away and we revisit the same problems day in and day out," her father said. "It really is demoralizing."
"The problem is they are trying to portray parents of autistic children as the next 'Erin Brockovich,' fighting the industry to own up to vaccines that cause autism," said Hotez. "It's high drama, but it's not factual. It takes away from the focus and time we have to really study the issue."