Safety of Vaccine Schedule Affirmed

Childhood immunization schedule considered safe by Institute of Medicine

(RxWiki News) Parents have often expressed concerns about the safety of children's vaccines. Now the gold standard of approval has been given to the childhood immunization schedule.

The Institute of Medicine (IOM) has issued an extensive report that emphasizes the safety of the CDC's childhood immunization schedule based on current research.

"The IOM committee finds no evidence that the schedule is unsafe," the report stated. The committee found no evidence that the vaccine schedule was linked to autoimmune diseases, asthma, developmental disorders or other health concerns.

"Follow the CDC vaccine schedule."

The report, produced by a 14-person committee, noted that about 90 percent of American children received the majority of vaccines on the schedule recommended by the US Centers for Disease Control and Prevention.

Still, some parents have been concerned in recent years that children are given too many vaccines or too many vaccines at one time during well child visits (up to five shots in a single visit). The schedule includes 24 total immunizations by the time a child is 2 years old.

Therefore, the committee reviewed all the research related to the safety of the schedule, including individual vaccines and the administration of multiple vaccines at a time.

The committee also consulted researchers, advocacy groups, federal agencies, advisory committees, parents, healthcare providers, international organizations, media, nongovernmental (nonprofit) organizations, philanthropic organizations and vaccine-related industries, distributors and investors.

The committee's overall finding was that the current CDC schedule is safe for children.

"The committee’s review did not reveal an evidence base suggesting that the US childhood immunization schedule is linked to autoimmune diseases, asthma, hypersensitivity, seizures, child developmental disorders, learning or developmental disorders, or attention deficit or disruptive disorders," they wrote.

The committee noted that continuing to study the safety of vaccines is important and that current systems for gathering and studying data related to vaccine safety are good tools for this.

The committee also discussed some of the public health problems that have arisen from parents' fears of vaccinating their children.

"Delaying or declining vaccination has led to outbreaks of such vaccine-preventable diseases as measles and whooping cough that may jeopardize public health, particularly for people who are under-immunized or who were never immunized," the committee wrote.

They noted that states with easy vaccine exemption policies had a pertussis (whooping cough) rate 90 percent higher than other states in 2011.

Jocelyn Ang MD, FAAP, Infectious Diseases Specialist at DMC Children's Hospital of Michigan and dailyRx Contributing Expert said "This is the first study done to examine the safety of the entire recommended childhood immunization schedule. This report should further reassure parents that following the current childhood immunization schedule is safe. Immunizing our children on time is important and is associated with reducing potentially dangerous vaccine preventable diseases."

Right now, the committee said the Vaccine Safety Datalink (VSD) currently in use is the most effective tool available to use in looking at specific safety concerns related to the childhood vaccine schedule.

The Vaccine Safety Datalink was established in 1990 through the CDC's Immunization Safety Office and nine managed care organizations who collaborate on collecting information about adverse events from vaccines. It's a safety monitoring system with data regularly used in vaccine safety studies.

The data in the Vaccine Safety Datalink includes demographic information about individuals getting vaccines, the type of vaccine they get, when they get it and any illnesses or potential reactions or other health concerns they experience afterward. It also tracks children who are vaccinated according to the CDC schedule as well as those who receive shots on alternate schedules so that the groups can be compared.

The Vaccine Safety Datalink is limited since it only receives information reported from eight states, but it still provides valuable data, the IOM stated.

The IOM also addressed a common request among those who criticize current immunization policies in the US: that researchers conduct a randomized controlled trial comparing vaccinated children with unvaccinated children.

The IOM noted the ethical impossibility of this kind of study since the children intentionally unvaccinated would be at greater risk for contracting disease. Further, parents who do not want to fully vaccinate their children may object if their child were randomly assigned to the "vaccinated" group.

Another study option would be to compare the children whose parents have elected not to vaccinate them to those who are fully vaccinated. The IOM noted that such a large, expensive study would provide less definitive evidence of differences between groups since an observational study is not as scientifically useful as a clinical trial.

Further, less than 1 percent of Americans refuse all vaccines, so it would be difficult (and expensive) to find enough children to participate and then match them to a group of vaccinated children in terms of age, geography, race/ethnicity and gender.

The IOM also noted that they have conducted over 60 vaccine safety studies since the late 1970s, but this is the first study to look at the entire current childhood immunization schedule as a single unit.

The report was sponsored by the US Department of Health and Human Services. The IOM was established by the National Academy of Sciences.

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Review Date: 
January 15, 2013
Last Updated:
August 19, 2013