Pediatricians across the country agree that delaying or eliminating any vaccinations is a definite no-no. So why are some parents going rogue when it comes to scheduling their child’s vaccines? Here are the facts.

vaccines on top of calendar
Photo illustration by Sarina Finkelstein; Getty Images (2)

When parents carefully follow the well-researched immunization schedules set by the Centers for Disease Control and Prevention (CDC), their children are fully protected against 15 vaccine-preventable diseases before they leave high school—13 of which they are protected from by the age of six.

However, some parents have been picking and choosing which vaccines to give and when to give them, which leaves their child exposed to potentially deadly diseases—and some doctors are even letting them. Why? 

In 2007, Dr. Robert Sears published The Vaccine Book: Making the Right Decision for Your Child. Sears’ book includes “Dr. Bob’s Alternative Vaccine Schedule,” a formula by which parents can delay, withhold, or space out vaccines. In turn, Dr. Sears has many parents doubting the seriousness of diseases and the importance of vaccination. 

We went to the experts to better understand the dangers of parents deciding to go against the CDC's vaccine schedule and clear up misinformation around the safety of an "alternative vaccine schedule."

Here are the five most important things we learned:

#1 Skipping Vaccines Will Destroy ‘Herd Immunity’

Dr. Sears states in his book that vaccines should be optional and all unvaccinated children have protection due to “herd immunity.” But the concept is one that we’ve been taking for granted. 

The “herd” is a community of vaccinated people that create a barrier from disease. This barrier protects tiny babies as well as children who are too sick to be immunized; but it only works when all of the healthy people get their vaccines. Parents are wrong to think that the immunized population will protect their children when they can’t even count on the people around them to do their part, too. All parents need to follow the schedule for herd immunity to work and eliminate disease.  

As more parents take Dr. Sears’ advice to rely on the herd to protect unvaccinated kids, the more the herd falls apart. When this happens, pockets of unvaccinated people form and disease has a way to enter communities. This can create outbreaks. 

Unfortunately, it’s the children who are too sick or too young to be vaccinated that will most likely get these diseases and have serious complications. As we saw with the measles outbreaks this year, babies who aren’t able to get the MMR vaccine until their first birthdays, are affected the most. 

#2 There Is No 'Alternative Vaccine Schedule' Approved by the CDC

The vaccine schedule is set by CDC, based on the recommendations and approval by the Advisory Committee of Immunization Practices (ACIP), American Academy of Pediatrics (AAP), the American Academy of Family Physicians (AAFP), and the American College of Obstetricians and Gynecologists. 

Alternative schedules, on the other hand, haven’t been tested and aren’t considered safe. 

"There is wonderful, researched-based data regarding vaccine safety, and appropriate vaccine schedules, that is not financially sponsored by the vaccine manufacturers," says Robert Weiss, MD, of Weiss Pediatric Care, who strongly discourages the alternative vaccine schedule.

#3 Spreading Out Vaccines Would Cause More Stress for Everyone

The Children's Hospital of Philadelphia (CHOP) equates the breaking-up of vaccines to making a meal by purchasing one ingredient at a time. The meal may be the same, but there's much wasted time and money by doing it that way. Like the analogy of going to the grocery store every day of the week, alternate vaccine schedules require more visits to the doctor, more needle pokes, and lots more stress and trauma to both the parent and the child.

Sticking to the schedule is also a no-brainer when it comes to time-management. The vaccines weren’t just randomly chosen and placed on the schedule. They were carefully researched and placed there for a reason. Boosters need to be given at the proper age increments so that the child’s body will make the best possible immunity that it can. That’s why parents can’t just pick and choose which vaccines they want to get their child whenever they want to get them. Vaccines don’t work best that way.   

#4 Baby's Immune System Is Much Better Able to Withstand Vaccines Than You Think

According to nurse practitioner Erin Gennocro of Weiss Pediatric Care, one of the biggest concerns she hears from parents is that there are too many vaccines given at a time which may overload their child's immune system.

The fact is that a small child's immune system is much stronger than we think. According to a report by the Institute of Medicine, if all 14 childhood vaccines were given at once, only slightly more than 0.1% of a healthy baby's immune system capacity would be at work.

Yes, our children get more vaccines than ever before, but the vaccines now are more efficient and surprisingly better for us than they were when we were kids. Our vaccines today have fewer disease components, fewer ingredients, and help create better responses. Even more, our kids are more fortunate than we were, as they are protected from more diseases. 

As a microbiologist and vaccine researcher, I’m confident when I say that there’s no benefit to changing up the vaccine schedule because there really is no overloading a healthy child’s immune system. A baby's body is always working to fend off intruders, as they are exposed to so many germs all the time. If a child isn't too young to get a disease, then their bodies aren't too immature to get the vaccine.

#5 Your Pediatrician Is Your Best Source of Vaccine Information 

Parents, it’s okay to ask your pediatricians questions about vaccines. They want you to. Health officials understand the research and are eager to help families learn about the benefits of vaccinations.

"As a mother of two children, I have comfortably and confidently had both children vaccinated with all the recommended vaccines," says Gennocro, whose patients trust her as both a doctor and a mother. 

Providers emphasize educating parents on the risks of not vaccinating their children according to the schedule. “We discuss the recommended vaccine schedule, answer any questions parents may have about the vaccines and/or schedule, provide research-based information, and review Weiss Pediatric Care’s policy,” says Dr. Weiss. “If parents still decline to follow the recommended schedule, we do ask them to find another provider.”

Weiss Pediatric Care’s policy states that vaccines are the single most important health-promoting intervention that they can provide. Delaying or breaking up vaccines goes against experts’ recommendations and puts children at risk for disease, serious illness, and even death. Doctors at the Weiss Pediatric Care are choosing wisely by not letting parents stray from the schedule, as children need to be protected from serious disease. 

The good news? When it comes to education, vaccine-hesitant parents are listening to their pediatricians. "We are impressed by the increasing number of otherwise initially skeptical families who have moved their line to embrace the wisdom of following the AAP vaccine schedule after our discussions. It is time well spent," says Dr. Weiss.

The Bottom Line

According to, AAP pediatricians "strongly recommend timely vaccinations because of what we know to be true: Vaccines are simply the best way to protect our children from these viruses and bacteria that can cause real and devastating harm."

Taryn Chapman, otherwise known as The Vaccine Mom, is a medical molecular biologist and mother of two. You can find more at