Michele Norris speaks with Dr. Carol Baker, chair of the CDC's Advisory Committee on Immunization Practices and professor of pediatrics at Baylor College of Medicine. She describes how the CDC determines the schedules for children's immunizations.

MICHELE NORRIS, host: The recommendations for vaccines are set by the Centers for Disease Control and Prevention. An advisory committee decides which vaccination should be administered and when. And Carol Baker is chair of that committee. She's a professor of pediatrics at Baylor College of Medicine, and she's also a specialist in infectious diseases at Texas Children's Hospital. And she joins us now.

Welcome to the program.

Dr. CAROL BAKER: Thank you.

NORRIS: Dr. Baker, I want to lay down the basics first. If someone has a baby right now, this year, how many vaccines does the CDC suggest that that child should receive?

BAKER: Well, in the first two years of life, the number of vaccines would be approximately 12. And some of these can be combined into a single shot, and that's including the yearly influenza vaccine.

NORRIS: You know, take me back. Has there generally been a resistance to vaccines or were they seen as a panacea to a difficult health problem?

BAKER: Well, I think in the 1950s when we had polio epidemics all around our country, we had people lining up in churches, parking lots, whatever, to receive the Salk vaccine, which was a shot. And that's because everybody knew somebody with polio or multiple people with polio.

Now that we've had so many successes in preventing vaccine-preventable diseases like polio and meningitis, the diseases have disappeared from common view. And in that way vaccines have sort of defeated themselves.

NORRIS: Now, I understand that you have a particular point of view. But for the parents that are out there listening to this conversation and have young children, they're making decisions about vaccination, what would you say to them? What do you say in particular to parents who are considering opting out?

BAKER: Well, I - you know, some parents, you can tell in the first two minutes of the conversation that - and this is very few, but they could cluster in a school, like the story from Seattle, for example - where you can tell immediately that no matter what you say, they're just not going to have their children vaccinated with any vaccines.

And so, I would continue to take care of those children, continue - would tell them at the end of the two-minute conversation that every time they come, I'm going to talk about vaccines. So they have to put up with it.

But the majority just want information. They've heard all these frightening things. They want the best for their children. And you need to educate them first about the diseases, because they don't know about the diseases.

NORRIS: Now, we want to be careful not to overstate or amplify a trend. Martin Kaste reported that 6.2 percent of kindergartners in Washington state get exemptions. But looking at these figures nationwide, less than one percent of children are getting zero vaccinations. That seems like a pretty tiny proportion.

It is a tiny proportion. However, if you have a large number in your community, then you lose what we call the herd protection. And that can lead to epidemics and outbreaks and spread to children. And some children will be exposed to diseases not because their parents didn't choose to get a vaccine, but because they're too young to be vaccinated. So these children end up being exposed even though their parents would like them to have them protected.

Dr. Carol Baker is a specialist in pediatric infectious diseases. She's also the chair of the CDC's Advisory Committee on Immunization Practices.

Dr. Baker, thank you very much for your time.

My great pleasure, thank you.

MELISSA BLOCK, host: ..COST: $00.00 Transcript provided by NPR, Copyright National Public Radio.