It’s also high-wire advocacy, fraught with emotion and division, rancor and suspicion. And hate mail. Enter Amanda Peet, actress (starring most recently in the crime drama What Doesn’t Kill You), new mom and self-described cynic. When it came time to vaccinate her baby, many of her friends said: Beware. Beware of drug company collusion with researchers. Beware of vaccine vials filled with questionable materials. And beware of autism — rumors link the disease to childhood vaccines. So in her quest to learn the truth, Peet did what any good actor would: She questioned the script and researched the field. Peet started by interrogating her pediatrician brother-in-law. Then he introduced her to Paul Offit, MD, an expert on immunization, who gave her a primer on vaccines. Now, as the spokesperson for vaccinateyourbaby.org, a national public service campaign, she’s helping parents separate facts from fiction and science from, yep, cynicism.

Peet spoke about life as a vaccination advocate with Paul Costello, the School of Medicine’s executive director of communication and public affairs.

You were about to have a baby and were hearing ominous warnings from some of your friends about vaccines. What were they telling you?

Peet: They were telling me many frightening things: that vaccines cause autism; that vaccines contain ether, aborted fetuses, antifreeze; that the pharmaceutical companies manipulate the safety data; and that the government agencies responsible are corrupt and too lazy to look into this.

Did you believe it?

Peet: Some arguments sounded more believable than others. But I’m constantly talking to my brother-in-law, who is a pediatrician and an infectious diseases fellow at Children’s Hospital of Philadelphia. After he started to explain some of the science I felt reassured, and eventually he said, you know, you should really talk to Paul Offit about this. He’s one of the world’s leading authorities on vaccines.

And what were you really seeking from Paul Offit?

Peet: I consider myself to be a fairly skeptical person. So it was interesting to learn how rigorous the screening process is for vaccines compared with the screening process for, say, Vioxx. A lot of people think that pharmaceutical companies are fudging all the data on vaccines, and that the CDC, the NIH and the rest of the medical establishment are all in cahoots in a massive cover-up.

The grand conspiracy.

Peet: Yeah, it didn’t seem that realistic. But one thing that did concern me was the rumor that some babies are born with a genetic vulnerability to the so-called toxins in vaccines and they can’t handle today’s recommended vaccine schedule. Obviously, I’m not a biochemist — I was even a dismal science student in school — so trying to learn about the ingredients in vaccines is especially difficult. I tried to grasp, as best I could for a layperson: what an antigen is, how vaccines are created, how scientists inactivate bacterial and viral components but make them so that they still cause an immunological response. I had several tutorials with my brother-in-law and Dr. Offit, and my family doctor, my ob/gyn and my pediatrician. I just started talking to anybody and everybody. What I really found out is that I have no aptitude for science and that I know nothing.

But the scientific community is in consensus that vaccines are one of the greatest medical advances in history. Did that help you?

Peet: Of course. Since I’m standing with the entire medical community I feel like I’m in pretty good company.

Why did you decide to advocate for vaccination, knowing that it would be so controversial?

Peet: Well, I certainly blame my brother-in-law. He should really be doing this interview, but he’s probably too busy. I just became scared by the sheer number of parents I know who are staggering vaccines or who aren’t vaccinating. It started to make me afraid for my daughter’s health. And I don’t want to sound paranoid, I don’t want to put a bubble around her or anything, but I know more people who are withholding their children’s vaccines or staggering them than people whose children are on the full schedule. This is my community, though, and I know I live in a rarified world.

The interesting thing to me about the Hollywood community is that it embraces the scientific evidence for global warming and climate change, but ignores the scientific data showing no link between vaccines and autism.

Peet: Yes, well, we are whistle-blowers here in Hollywood — we like to think of ourselves as anti-corporate and anti-establishment. And I don’t trust pharmaceutical companies either. But the scientific evidence in the last 10 years shows there’s no link between autism and vaccines. There have been 12 studies showing that the MMR vaccine, the one so many are worried about, doesn’t cause autism. And while it’s natural to be cynical, I think it’s critical to be discerning.

Have you lost any friendships because of your advocacy?

Peet: Yes. But it was not a very close friend.

Do you understand the fear people have?

Peet: If I perceive something as a threat to my daughter I have a very visceral response. Doctors and scientists are telling parents of children with autism that they can’t find a cause and they don’t know how to help their children. I can’t think of anything more difficult, or that would make me more angry and cynical toward medical institutions.

You’re an actor and your husband’s a screenwriter — so you understand pitches. What’s your pitch to someone on why they should vaccinate their baby?

Peet: Oh no, you’re putting me on the spot [laughs]. I’d say just look at the data. I think vaccine opponents don’t want to talk about the data because they’re hard to dispute. But nobody in the medical community is saying that the studies lack objectivity or scientific rigor. It’s hard to argue that reproducible, transparent data are biased — they’re inherently unbiased. All people want to do is talk about this person’s conflict of interest, or that person was paid by Merck, and my point is: Look at the studies. The studies were not performed by Merck.

What do you hope to do as a spokesperson for the campaign?

Peet: My biggest hope is that I can be a bridge between the scientific community and parents. My sister and brother-in-law are both in academic medicine so I have an unusual perspective. Also I hope parents understand that when they do not vaccinate their kids, they are able to make that choice only because most of us are vaccinating. We are creating a barricade around their unvaccinated children and that is what keeps them safe. That’s a fact.

Has it been worth it?

Peet: Of course. It has nothing to do with me, you know. It has to do with what could happen in the future if fewer and fewer children are vaccinated.

Which side do you think is winning right now?

Peet: Well, immunization rates in the country are still fairly high, but we can’t be complacent.