• In a 1969 episode of "The Brady Bunch," the entire family contracts measles and stays home for a few days to deal with it.
  • In real life, measles is a dangerous contagious disease and vaccinations can prevent it.
  • Nonetheless, some anti-vaccine activists have cited the episode to play down the dangers of measles.
  • Maureen McCormick, who played Marcia in the show, said it was "really wrong" when she found anti-vaccination memes on Facebook citing the episode.
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Anti-vaccination activists are taking comfort in a 1969 episode of the fictional TV show "The Brady Bunch," which they say shows that vaccines aren't necessary to prevent measles.

Vaccines are a crucial component of staving off health threats like measles, according to public health experts. Measles is highly contagious, and vaccinating children is an effective and safe way to prevent epidemics.

But some people, like Dr. Toni Bark, oppose mandatory vaccination. Bark, who has a private practice in homeopathic medicine and autonomic biofeedback, often cites the "Brady Bunch" episode, titled "Is There a Doctor in the House?" when she testifies against mandatory vaccination at local government hearings, according to NPR.

In the episode, the whole family gets sick with measles and stays at home for a few days playing board games until the illness goes away on its own. The symptoms in the show are much more mild than in real life, which include a rash of red spots and high fevers. But to people like Bark, it illustrates how safe measles can ostensibly be.

Read more: 3 graphics show how the measles epidemic is getting worse across the US

Some former cast members of the "Brady Bunch" are furious that the show is being used to spread harmful misinformation about vaccines. Maureen McCormick, who played Marcia on the show, said she was upset when she saw memes referencing the show circulating in anti-vaccination Facebook groups.

"I think it's really wrong when people use people's images today to promote whatever they want to promote and the person's image they're using they haven't asked or they have no idea where they stand on the issue," she told NPR. "Having the measles was not a fun thing."

The number of measles outbreaks has been rising as anti-vaccination groups have continued to find a voice, according to the Center for Disease Control and Prevention. This year alone, hundreds of cases have been diagnosed in New York and California, the largest number since the disease was declared eliminated in 2000.