Vaccine Schedule: Altering the Schedule

Deciding whether to alter the immunization schedule

In this age of choices about everything from which songs are on our personal listening devices to which custom drinks we want at the local coffee shop, we are used to deciding what we want and don’t want for ourselves and our families. To some extent, this notion also pervades choices about healthcare. For example, some parents feel they should approach the childhood immunization schedule in an a la carte manner, giving their children only those vaccines that they feel are appropriate.

While this may seem reasonable on its surface, sometimes these individual decisions are not based on complete information or follow false logic. If you are considering this approach related to vaccinations for your child, please consider the following:

  • Evaluate each disease fairly. All diseases are not created equal. Some are very scary; some are more deadly; and some are more easily spread. Unfortunately, the ones that are deemed less scary, less deadly or less contagious may seem like good candidates to forego when choosing vaccines. This kind of logic is like deciding only to treat one’s cancer if it is more deadly or affecting a certain part of the body. The fact of the matter is that every type of cancer — and every vaccine-preventable disease — can kill or cause permanent harm. Whether the death rate is 1 in 100 or 1 in 10,000, we can’t predict who will be spared and who will not.
  • Consider whether vaccine immunity is “good enough.” When the disease is considered mundane, some parents would prefer that their children experience the infection rather than the vaccine in part because diseases often create stronger immunity than vaccines. Parents should remember, however, that the disease is not mundane for everyone. Vaccine-induced immunity is typically good enough, and immunity from vaccines comes without paying the price of natural infection. For example, although chickenpox is a benign disease in most, every year before the chickenpox vaccine was first available, about 70 children died from the disease, most of whom were previously healthy. Because we never know who is going to be severely affected by chickenpox, all children are recommended to receive the vaccine.
  • Realize the full scope of the “wait-and-see” approach. When a new vaccine is developed, some people prefer to delay using it to "make sure that it works well and is safe." However, each vaccine must be extensively tested before being added to the schedule, and millions of vaccines are given by the approved schedule each year. Some parents arbitrarily make up a schedule based on personal preferences. However, the current schedule is well tested; the made-up schedule isn’t. Other parents might choose to “wait and see” if new vaccines are safe despite the existence of data from tens of thousands of people and years of studies before licensure. In both instances, these decisions disregard existing data, leaving the child susceptible to the disease for a longer period of time and providing a false sense of benefit. See “Waiting for more information could be dangerous” below for more information.
  • Understand the importance of timing. Many parents focus on the number of vaccines given at a single visit and understandably feel that there are too many given at once, particularly for younger infants. However, three issues should be considered:
    • Vaccines are added to the schedule based on when an infant is likely to be most susceptible to the disease. During the first few months of life, babies are somewhat protected from infectious diseases by maternal antibodies present in their bloodstream at birth or in their mother’s milk. However, protection afforded by maternal antibodies wanes during the first year of life and is somewhat variable. For example, studies have shown that maternal antibody levels in the infant's bloodstream increase beginning at around 32 weeks of gestation, so babies born prematurely tend to have lower levels than their full-term counterparts.

      Because the length of protection and robustness of the maternal response cannot be predicted, eliciting the infant’s own immune response before the maternal response wanes is the most conservative approach.
    • Because most vaccines require more than one dose, limiting the number given at one appointment makes getting the doses in a timely manner a tremendous feat. A small percentage of parents have willingly scheduled monthly visits to the doctor’s office to give only one or two vaccines to their child at a time. This is similar to the difference between going to the grocery store every day to get the ingredients for dinner and getting a single order on the weekend; in the long run, you have accomplished the same thing, but you’ve probably spent less time and money if you used the latter plan. Unfortunately, when it comes to childhood vaccines, the decision goes beyond time and money because children who are given vaccines one or two at a time are vulnerable to some diseases longer and may experience more stress. Specifically, in a study completed a few years ago, children given multiple vaccines at once did not experience more stress than children given only a single shot, so multiple visits to the doctor could cause more stress and increase the chance of needle phobia over the long term.
    • If a baby is not too young to get the disease, they are not too young to get the vaccine. All vaccines expose recipients to a smaller number of antigens (parts of viruses or bacteria that generate an immune response) than the actual virus or bacteria. Even when multiple vaccines are given together, the number of antigens is limited compared with the number of pathogens to which infants are exposed during a normal day. The difference is we know when our children were exposed to antigens through a vaccine, but we aren’t always aware of their exposures to diseases. For more about the number of antigens, see “Vaccines impact on the immune system” in the Vaccine Safety section of the site and the “What is an antigen?” infographic.
    • Consider ingredients in the appropriate context. Many vaccine-related concerns center on the ingredients that are in vaccines. Contemplating giving our children aluminum, mercury, formaldehyde or any of the other oft-mentioned chemicals in vaccines can be scary; however, thinking about what is in a vaccine should be kept in perspective. For example, consider how we have all become adept at reading nutrient labels; ingredients like unsaturated, polyunsaturated, and trans fats are in many foods; however, we evaluate the foods based on the quantities of these items. The same should be true for vaccines; the quantities of ingredients in vaccines are not sufficient to cause harm even when multiple vaccines are given at the same time. Further, the quantities of vaccine ingredients that at very high levels could do harm (like mercury) are well below the levels that are harmful. To find out more about specific vaccine ingredients, check the “Vaccine Ingredients” section of our website.

Vaccines are arguably the safest, best-tested products we put into our bodies, so the choice not to get them is a choice to take a different and much more potentially serious risk.

Watch as Dr. Offit talks about altering the vaccine schedule in this short video, part of the Talking about Vaccines with Dr. Paul Offit video series.

Waiting for more information could be dangerous

Sometimes parents ask us whether they should wait for more information before getting their child vaccinated, especially if the vaccine is relatively new. They prefer to take a “wait-and-see” approach, thinking this is the most prudent, and perhaps safer, approach.

Unfortunately, a “wait-and-see” approach just changes the risks. When we speak to parents who are choosing to delay vaccines in order to get more information, we hear similar reasons:

Distrust or misunderstanding of science

The concern

People may not trust science for a variety of reasons — they didn’t understand or like science in school; they have religious beliefs that they feel conflict; or they don’t trust the entities that produce science (government, industry, etc.). However, science is central to much of human progress, and adults increasingly need to make decisions based on topics that have a scientific underpinning.

The solution

Science is not knowing facts like the earth is round or force equals mass times acceleration. Rather, it is a way of knowing and understanding the world. And while many don’t feel that they understand or like science, the reality is that people use science all the time. For example, what do people do when they cannot find their keys or their internet is not working? Without realizing it, they go through a series of small “experiments” to solve the problem. That is the essence of science — having a question (Where are my keys?), forming a hypothesis (My keys are in the kitchen.), testing the hypothesis (I am looking on the counter, next to the refrigerator, on the desk, etc.), and drawing a conclusion (My keys must not be in the kitchen.). The more places in the kitchen the person looks without finding the keys, the less likely the keys are in the kitchen. Of course, it can never be said for sure the keys are not in the kitchen, but the more one looks without finding them, the more confident the person becomes that the keys must be somewhere other than the kitchen.

The conflict arises when people deny or “cherry-pick” facts because the facts don’t agree with their beliefs. In the case of vaccines, some people prefer not to get their children vaccinated because it conflicts with their religious beliefs; but religions generally do not advise against vaccination. Generally speaking, religious support arises from two main tenets. First, protect and care for your children. Vaccines protect children by preventing suffering from disease. Second, do unto others as you want done unto you. We do not live in isolation, so our decisions affect others. In the case of vaccinations and diseases, the reality is that some people cannot get vaccinated, so they rely on those around them to protect them from infectious diseases. Science provides us with a way to know that vaccines are safe and effective; religion provides us with the moral compass and belief in protecting our children and neighbors.

Finally, historical examples of ways that government and industry earned mistrust certainly exist. However, trusting science is not about trusting the people doing science or delivering the message as much as it is about the facts being shared and how they were established.  Science-based information should be evaluated by the strength of the data — the entire body of data related to the information not just one study or report. 

Lack of understanding of risks/benefit

The concern

As VEC Director Dr. Paul Offit is fond of saying, “Choosing not to vaccinate is not a risk-free choice. It’s just a choice to take a different risk.” In fact, doing nothing is actually doing something — it is choosing to risk the chance of getting a particular disease.

Consider this to be like driving above the speed limit. Many people will speed without being caught, but some will not be so lucky and suffer consequences like having an accident or getting a speeding ticket. Because of how well vaccines work, today’s parents no longer see diseases like measles, mumps, polio or diphtheria, among others. Consequently, a risk/benefit imbalance is created in which the vaccine seems more risky than the disease. The reality is that while many of the diseases that vaccines prevent are not reported regularly in the news, they affect lives. Doctors working in hospitals and public health officials working in the community can attest to this — and that is why they are often so passionate when discussing the importance of vaccinations.

The solution

Vaccines allow parents to control the risk of disease by controlling the child’s exposure to the germ. They have the benefit of knowing the day and time their child is exposed, and they know the dose is one that will provide immunity without making the child suffer the symptoms of disease.    

Fear of getting it wrong

The concern

Parents just want to do what is right, so when they feel like not enough is known, they wait for more information to become available. This would be akin to not using a car seat because of uncertainty about how to install it or while waiting to see if a better one is developed.

The solution

Realize that “getting more information” may mean two things. Some questions may already have answers. Even though an individual may not know the answer, the answer may be out there. To that end, people should ask their doctor questions. However, sometimes parents who “wait and see” talk about waiting for others to get a vaccine to see what happens. In this case the concern is more about how well studied the vaccine was before it was licensed. Most vaccines have been studied for 25 to 30 years before they are licensed. So the notion that a vaccine is “new” is not exactly accurate. For example, the human papillomavirus (HPV) vaccine was studied for seven years in 30,000 people before it was licensed. Vaccines are not licensed or recommended until a large body of evidence shows them to be safe and effective. So, while new information may eventually be learned, giving a recommended vaccine is still making a decision based on knowledge not based on inaction or theoretical concerns that may or may not be realized.

Parents just want to do the best for their kids. That means separating knowledge from emotion and realizing that inaction is still an action — one that could lead to suffering for their child.

Other resources

Reviewed by Paul A. Offit, MD on January 02, 2024

Materials in this section are updated as new information and vaccines become available. The Vaccine Education Center staff regularly reviews materials for accuracy.

You should not consider the information in this site to be specific, professional medical advice for your personal health or for your family's personal health. You should not use it to replace any relationship with a physician or other qualified healthcare professional. For medical concerns, including decisions about vaccinations, medications and other treatments, you should always consult your physician or, in serious cases, seek immediate assistance from emergency personnel.