Nearly all pediatricians and family doctors have been asked at least once by parents if they could "space out" the vaccines their children get and most have agreed to do so at some point, a new study finds
The main reason given is that doctors are afraid of losing their patients - costing them business but also potentially leaving innocent children without good health care, according to the survey published in the journal Pediatrics.
The study's especially timely as the nation debates whether parents have the right to leave their children less than fully vaccinated because of personal beliefs and worries. Such vaccine doubters are being blamed for the outbreak of measles linked to Disneyland that's made at least 133 people sick.
"This has been a huge issue for several years," said Dr. Sean O'Leary of Children's Hospital Colorado, who helped lead the study.
There's no medical reason to spread out vaccines, but many parents seek to, worried that getting five or more jabs on a single day may somehow overwhelm a baby. And O'Leary acknowledges it can be upsetting to watch a trusting baby dissolve into frightened and puzzled tears as each soft thigh gets pierced with a needle.
"The debate is really emotion versus science," O'Leary told NBC News.
His team surveyed 534 pediatricians and family doctors. Nearly 93 percent said they'd been asked by parents of children under 2 to delay or spread out vaccines. Of them, 37 percent said they often or always agreed to do so. Another 37 percent said they sometimes did.
So that's 74 percent of doctors agreeing to alter the vaccine schedule against expert advice and against their own training.
"I am not surprised how high the numbers are," O'Leary said. "It is one of those things that for families may seem like a logical choice. They will say things like, 'This is what we think is best for our family.' The pediatrician is kind of stuck."
When asked why they agreed to alter the vaccine schedule, most pediatricians said they were worried the patients would just find another doctor who would. "They wouldn't have any patients," O'Leary said.
Under the current schedule, kids should get about 25 different vaccinations by age 6, protecting against 14 different diseases, including polio, rotavirus, measles, influenza, a family of bacteria that cause pneumonia and other ills.
Many of the vaccines are combined so that only one injection is needed. They include measles, mumps and rubella, which come in one MMR shot, and the diphtheria, tetanus and pertussis (whooping cough) combined vaccines. But most require more than one dose to provide full protection.
All the combinations have been tested to make sure they work well together. For instance, MMR once had chicken pox added to the mix, but it caused a few more side effects so that combination was dumped.
And immunologists argue that the children are not actually being given a big challenge in any of the shots.
"It's estimated that an infant could respond to 10,000 vaccines at once," O'Leary said.
"Just think of the germs your kid is getting exposed to when they are in one of those ball bins in the fast food restaurant."
"When you are infected with bacteria or a virus, you are exposed to hundreds of antigens in that infection," says Dr. Richard Rupp, a pediatrician who helps develop vaccines at the University of Texas Medical Branch. "With most all of the vaccines, you are just exposed to just one or two." An antigen is a substance that stimulates the immune system.
"From the time they are born, babies are exposed to thousands of germs and other antigens in the environment and their immune systems are readily able to respond," the Centers for Disease Control and Prevention says.
"Eating food introduces new bacteria into the body; numerous bacteria live in the mouth and nose; and an infant places his or her hands or other objects in his or her mouth hundreds of times every hour, exposing the immune system to still more antigens." One case of strep throat exposes a child to between 25 and 50 antigens, the CDC says.
To parents who are worried about metals such as mercury or aluminum in vaccines, the CDC says kids get more of those metals in breast milk than they ever did in a vaccine.
And a child who is not vaccinated on time is vulnerable to infection.
But explaining this to hesitant parents not only takes up scarce time; they may also reject the explanation, O'Leary said.
"There is really a sort of questioning of science in general. We are in an environment now where for some parents, somebody can say something, can just make something up and that can hold sway with a parent as much as hundreds of scientific studies," O'Leary said.
"It is a big burden on their time talking parents through these alternative schedules," he added. And multiple office visits are a pain for everyone.
O'Leary said he got angry when he was a young doctor just starting out and parents asked to let the vaccine schedule slide. He tried explaining they were putting their child in far more danger by driving in the car to multiple visits than the children would ever be in from a vaccine. "Sometimes that clicks," O'Leary said.
Another argument he hears is about "purity." "People have now lumped vaccines into those buckets, organic food and knowing what is in the food they are giving their kids," he said,
"When you look at the list of ingredients on a vaccine label, some of the names look scary."
But they have been tested for years before any vaccine goes on the market, and are constantly scrutinized as they are used in a general population.
Most arguments do not work on a worried parent, O'Leary said. The best persuader, he says, is when a doctor can say "I vaccinate all my own kids, and on time."
He's hoping the ongoing measles outbreak, and the attention it's focused on vaccine doubters, may turn the tide.