“I’m not against vaccines. I just want a safer schedule,” says Kim Taylor, with her son, Noah, 14, at their home in Edgewater, Md. (Mary F. Calvert/For The Washington Post)

The letter arrived in the midst of a growing furor about the country’s worst measles outbreak in years.

Cindy Shay, a Maryland health-care lawyer, had been taking her children to Bayside Pediatrics in Annapolis for a decade when her doctor wrote last month that he was “no longer able to continue as your child’s pediatrician.”

Her twin 13-year-olds are up to date on all state-mandated vaccines, Shay said. But she was told that the practice also wants them to have boosters and new vaccines recommended by the Centers for Disease Control and Prevention and the American Academy of Pediatrics. Shay has questions, as she has since her son lost his ability to speak and was diagnosed with autism shortly before his second birthday.

“I’m an attorney,” Shay said. “Research is what I do. I think parents should ask questions and inform themselves.”

It’s a tough time for parents to express doubts about vaccines. The measles outbreak that began at Disneyland in December has spread to 14 states and infected more than 100 people. On Tuesday, D.C. health officials confirmed a case of measles in the District that they say is linked to international travel. The disease’s march, public health officials say, has been fueled by pockets of unvaccinated children, including those of members of anti-vaccine movements in California and other places.

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The debate has become both medical and political, with President Obama and 2016 presidential contenders weighing in this week. The outrage online, on television and in social media has been ferocious, with parents condemning “anti-vaxxers” for putting other people’s children at risk.

The backlash has spread like an epidemic through pediatric practices, pre­schools and play groups, becoming a topic of blistering discussion on community e-mail groups. Parents who harbor doubts about vaccines say they feel as if they are flunking a new litmus test for sanity.

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“I get angry that we’re all lumped together as anti-vaxxers,” said Alison Hamilton, who has a 14-year-old daughter with autism and is the co-coordinator of the Maryland chapter of Talk About Curing Autism, an advocacy group. “Parents who are just asking questions are labeled as crazy, as selfish. We’re not all followers of Jenny McCarthy,” she said, referring to the outspoken celebrity closely associated with the anti-vaccine movement.

Hamilton hears regularly from parents who feel caught between the certainty of the medical establishment that vaccines are safe and the anguish of their fears that shots might permanently injure their babies.

“It’s a very easy view to take when your child has never spiked a fever, lost all language, and become someone who will require care for the rest of their lives, with very few adequate supports available,” said Hamilton, whose husband works in information technology at The Washington Post.

Kim Taylor with her sons, Dawson, 12, left, and Noah, 14. Because Noah will need a tetanus booster and the meningitis vaccine to run track, she’s negotiating with her doctor to go slowly. (Mary F. Calvert/For The Washington Post)

While Shay doesn’t necessarily attribute her son’s autism to the battery of shots he got as an infant, she began to worry about their number and intensity in light of a sharp rise in food allergies and autoimmune disorders. She’s become cautious. She has spent “thousands of hours” looking at vaccine safety studies and the relative risks of the diseases they prevent.

Until last month, Shay said her doctors have been willing to work with her concerns. When it came time for a measles, mumps and rubella (MMR) booster, she paid for a blood test that showed her children already had sufficient immunity from their first shots, a substitute that most doctors accept. The practice agreed, signing school and sports forms that certified them as up to date.

Now, Bayside won’t continue seeing her daughter unless she gets a range of new shots: boosters for tetanus, polio, chicken pox and MMR, and new vaccines for meningitis and human papillomavirus (HPV).

Shay thinks the meningitis shot may be a good idea. “That’s a nasty disease,” she said. But she’s hesitant about the others, which are not required by the state. Maryland doesn’t mandate HPV or a fourth polio shot, and new school requirements for boosters for tetanus and chicken pox apply only to children younger than Shay’s. She has doubts, but this time, the practice won’t accommodate them.

“They said they’ve changed the policy,” Shay said.

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The practice declined a request for an interview but said in a statement, “Our vaccine policy is based on the American Academy of Pediatrics guidelines and for the concern of the welfare of our patients who do vaccinate.”

Pediatricians say they, too, are torn between wanting to care for every child and ensuring that reluctant parents don’t erode the “herd immunity” that protects the whole society from polio, chicken pox and measles.

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Gary Bergman, a longtime Virginia pediatrician, said he has never had to expel a patient, because he won’t admit children who have not received their scheduled immunizations.

“We just think it would be morally and legally neglectful to have people sit in our waiting room who might infect other children,” said Bergman, who practices in Alexandria. “I tell parents: ‘I respect your feelings, but I disagree with you. The science just isn’t there.’ ”

He said the number of parents looking to avoid vaccinations or tweak the schedule has declined in recent years. But in the past week, he’s been getting calls of another kind. More parents want to make sure all his other patients have gotten their measles shots.

The alleged link between vaccinations and autism was first raised in a small 1998 study by a British doctor, Andrew Wakefield, whose work has since been widely discredited in the scientific community. The journal that published the study retracted it in 2010, and Wakefield lost his medical license.

But Rita Montoya wasn’t worried about autism when she began to question the heavy slate of immunizations she was expected to approve for her 8-week-old son in the fall. The Northwest Washington mom did fear putting so much stress on her baby’s fledgling immune system. She suffers from an immune disorder, and she’s a big believer in natural medicine and nutrition.

She sought out a pediatrician who would be flexible, warily asking for advice on the same online discussion group where she had seen another woman “bullied” for questioning the vaccine schedule. But when she and her husband, both lawyers, expressed their interest in slowing the regime, the doctor wouldn’t budge.

“I’m a pretty strong-willed person, and I felt very pushed along,” Montoya said. “We got more than I was really comfortable with. I was crying when they were giving them to him.”

In the end, they delayed only the vaccine for hepatitis B, an infection that is typically transmitted through contact with body fluids. The doctor made them sign a waiver.

Kim Taylor is used to trying to wring as must wiggle room from the vaccine regime as she can. Her two sons, 12 and 14, are fully vaccinated, she said. But after her older son was diagnosed with autism at age 3, she decided to space out the shots as much as possible. She found a pharmacist to sell
her separate vaccines for the usually combined measles-mumps-
rubella shot. When her insurance company pushed her to combine them, she paid out of pocket for three separate doctor visits to have them administered.

Now her boys are aging into the next round. Her oldest will need a tetanus booster and the meningitis vaccine to run track. She’s negotiating with her doctor to go slowly, but she knows that resistance to giving parents any say is growing.

“I’m not against vaccines. I just want a safer schedule,” said Taylor, a graphic designer in Edge­water, Md. “It’s just very difficult to talk to people about it right now.”