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 in order 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.
  • 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 who are 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 all of the doses in a timely manner a tremendous feat. A small percentage of parents have willingly scheduled monthly visits to the doctor’s office in order 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 would cause more stress and more needle phobia over the long term.
    • If a baby is not too young to get the disease, she is 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.
    • 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.

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.

Other Resources

Reviewed by Paul A. Offit, MD on March 18, 2019

