For some reason, there still seems to be a lot of confusion out there about just how the immunization schedule is developed.

Who decides which vaccines we give and get?
How do they make that decision?
History of Immunization Schedule Development
While the current immunization schedule is developed by the CDC based on recommendations of the Advisory Committee on Immunization Practices (ACIP), that’s not how it was always done.
It has just been since 1995 that we have had this single, simple vaccine schedule and format.

Before that, we had separate vaccine schedules from the:
- American Academy of Pediatrics Committee on Control of Infectious Diseases
- Centers for Disease Control Advisory Committee on Immunization Practices (ACIP) – established in 1964
- American Academy of Family Physicians (AAFP)
- Armed Forces Epidemiological Board
Even earlier, we had recommendations and schedules from
- WHO Expanded Programme on Immunization (EPI)
- AAP’s Special Committee on Prophylactic Procedures Against Communicable Diseases – from its start in the early 1930s, it evolved into today’s Committee on Control of Infectious Diseases
- American Public Health Association Subcommittee on Communicable Disease Control
Differences in those schedules, which could lead to confusion, lead experts to create a simpler, unified schedule.
Well, at least in the United States. Of course, other countries still set their own schedules…
The Science Behind Setting the Immunization Schedule
Now that you know who sets the immunization, you are probably wondering how they set the immunization schedule.
To truly understand how the immunization schedule gets set up, it is best to go to an ACIP meeting when they make those decisions.
Can’t make it to Atlanta for one of the ACIP meetings?
You can watch them online!

Past ACIP meetings, agendas, minutes, slides, and videos, are archived online too.

Review them and you will get a very good idea of how the immunization schedule gets set up.
The first flu vaccine was developed in 1945.

Did you ever wonder why it took so long to get it on the immunization schedule?
Why was the primary series of polio vaccines made up of three doses?

Hopefully you are starting to understand how this works…
And no, all of this work doesn’t get done over a couple of days a few times a year. ACIP members belong to workgroups which focus on specific vaccines and they gather, analyze, and prepare information and research about those vaccines throughout the year.
It is at the ACIP meetings where the workgroup findings are presented.
“Development of vaccine schedules is based on a large body of basic sciences and epidemiologic research. There is constant review of evidence, adverse events, and epidemiology by a panel of experts.”
Shetty et al on Rationale for the Immunization Schedule: Why Is It the Way It Is?
And yes, among that body of research are studies of vaccines tested together, vaccines tested with placebos, vaccines tested vs unvaccinated kids, vaccines tested for long periods of time, and studies looking at risk factors to make sure vaccines don’t cause long-term health problems.
It’s a very thorough process!
And that’s why the great majority of folks understand that following the immunization schedule is the best way to keep their kids protected from vaccine-preventable diseases.
Vaccines are safe, with few risks, and are obviously necessary.
What’s not safe? What hasn’t been well studied?
Following a non-standard, parent-selected, delayed protection vaccine schedule.

Studies have actually shown that delaying or skipping vaccines offers no benefits and actually puts kids at extra risk.
It puts the rest of us at risk too.
More on Setting the Immunization Schedule
- Answers To Frequently Asked Questions About Immunizations
- Ask 8 Questions Before You Skip a Vaccine
- Anti-Vaccine Points Refuted A Thousand Times
- 100 Myths About Vaccines
- Vaccine Schedules from the 1940s to 2019
- What Is the Evidence for Alternative Vaccine Schedules?
- AAP – Rationale for the Immunization Schedule: Why Is It the Way It Is?
- CDC – Who sets the immunization schedule?
- AAP – The Recommended Childhood Immunization Schedule of the United States, 1995.
- WHO – Expanded Program on Immunization (EPI)
- WHO – Optimizing immunization schedules
- The Vaccine Schedule Explained
- Vaccine Timeline
- WHO – History of vaccine development
- Determination of the Immunization Schedule
- Immunization Policy Development in the United States: The Role of the Advisory Committee on Immunization Practices
- Study – Timely versus delayed early childhood vaccination and seizures.
- Study – Vaccination Status and Health in Children and Adolescents Findings of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS)
- Essential reading: A comprehensive takedown of Dr. Sears’ The Vaccine Book
- The Problem with Dr. Bob’s Alternative Vaccine Schedule
- Cashing In On Fear: The Danger of Dr. Sears
- Talking about Vaccines : Countering Dr. Sears
- Inventing your own vaccine schedule? Not a wise idea.
- Why Delay Vaccines For Your Child?