Childhood Vaccination

In the United States, vaccination of children and adolescents follows a schedule recommended by the Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control and Prevention (CDC):

• Child and Adolescent Immunization Schedule by Age

• Catch-up Immunization Schedule for Children and Adolescents

The schedules also are available as a free mobile app for health care professionals. Additionally, clinicians should consult the relevant vaccine-specific recommendations from the Advisory Committee on Immunization Practices (ACIP).

Vaccination has been profoundly effective in preventing serious disease. Given their modest cost (particularly in comparison to medications that must be taken long-term to treat infections and their associated morbidity), vaccines are one of the most cost-effective medical interventions. Vaccines have been so effective that many health care professionals currently in practice have seen few or no cases of diseases that were once extremely common and often fatal.

Because the diseases that vaccines prevent have generally become rare in the United States and vaccines are administered to otherwise healthy children, it is crucial for vaccines to have a high safety profile to be deemed acceptable by patients and caregivers.

Before U.S. Food and Drug Administration (FDA) approval and licensure, vaccines (like any medical product) are tested in randomized controlled trials (RCTs) that compare the new vaccine to placebo (or a previously existing vaccine if one exists). Such pre-licensing RCTs are designed primarily to assess vaccine efficacy and to identify common adverse events (eg, fever; local reactions such as injection site redness, swelling, and pain). However, some adverse events occur too rarely to be detected in an RCT of any practical size and may not appear until after a vaccine is marketed and enters routine use. Thus, 2 surveillance systems, the Vaccine Adverse Event Reporting System (VAERS) and the Vaccine Safety Datalink (VSD), were created to monitor vaccine safety post-licensure.

VAERS is a safety program cosponsored by the FDA and the CDC. It is a portal where individual patients who believe that they had an adverse event after a recent vaccination can submit a report. Health care professionals are also required to report certain events after vaccination and may report events even if they are unsure the events are vaccine-related. VAERS reports originate from all across the United States and provide a rapid assessment of potential safety issues. However, VAERS reports can show only temporal associations between vaccination and the suspected adverse event; they do not prove causation. Thus, VAERS reports must be further evaluated using other methods. One such method uses the VSD, which uses data from 13 sites that provide clinical, methodological, and data expertise; 11 of these are data-providing sites (1). The data include vaccine administration (noted in the medical record as part of routine care), as well as subsequent medical history, including adverse events. Unlike VAERS, the VSD includes data from patients who have not received a given vaccine as well as those who have. The presence of a control population in the VSD allows comparisons to be made. As a result, the VSD can help distinguish actual adverse events from symptoms and disorders that occurred coincidentally after vaccination and thus determine the actual incidence of adverse events. Despite the health benefits and established mechanisms designed to promote vaccine safety, some parents do not consent to vaccinating their children. (See also Vaccine Hesitancy.)

The following English-language resources may be useful. Please note that The Manual is not responsible for the content of these resources.

1. Children's Hospital of Philadelphia: Vaccine Education Center

2. European Centre for Disease Prevention and Control (ECDC): Vaccine schedules in all countries in the EU/EEA

3. Centers for Disease Control and Prevention (CDC): Vaccines For Your Children