|Key Vaccine Safety Elements
- The Federal government, including the Centers for Disease Control and Prevention
(CDC) and the Food and Drug Administration (FDA), as well as vaccine manufacturers
continually conduct vaccine safety research and surveillance investigations even
after vaccines are licensed for use. The National Vaccine Program Office (NVPO)
coordinates federal activities.
- Vaccine Safety is taken very seriously. The Federal government uses a
multi-component system to monitor and assess the safety of vaccines.
- The Vaccine Adverse Event Reporting System (VAERS), jointly managed by the CDC
and FDA, enables parents, health care providers, and manufacturers to report
what they believe are adverse events, or reactions to vaccines. Through VAERS,
investigators study and evaluate potential links between vaccines and adverse
events. Manufacturers are required to report known adverse events to VAERS.
- The Vaccine Safety Datalink (VSD) Project utilizes vaccine and health data
from several health maintenance organizations (HMOs) in order to study signals
from VAERS, and explore other vaccine safety research questions regarding any
unusual health conditions that may occur around the time of vaccination.
- The civilian and military sectors are in the process of developing clinical
centers to provide close monitoring of those experiencing previous adverse
events. The military centers will focus on reactions to the anthrax shot.
- The Institute of Medicine (IOM) assesses the proper level of public health
concern to adverse events and recommends appropriate action, such as
surveillance, research, or policy changes.
What is VAERS?
- VAERS is a tool for monitoring vaccine safety after a vaccine has been licensed
for use. Review of VAERS reports can provide additional assurance about vaccine
safety, and identify potential problems not observed during pre-licensure clinical
trials conducted by vaccine manufacturers because certain adverse events only become
apparent when a vaccine is used in a larger population. In the 1990s, 90 percent of
reports were non-serious.
- Anyone can make a report to VAERS, including health professionals, consumers, and
manufacturers. To report a health problem following vaccination, a patient, parent,
or health care provider can call VAERS at (800) 822-7967 to obtain a reporting form.
Forms can also be downloaded from the VAERS website: .
- Since the system accepts and includes all reports submitted, some events may be
due to other unrelated health conditions that occurred around the time of
vaccination. In other words, an event that occurs at the time of vaccination is not
necessarily caused by the vaccine.
- A recent example of how VAERS works is the safety evaluation of a new vaccine to
prevent a severe diarrheal illness in childhood caused by rotavirus infection.
Review of VAERS reports detected a rare health condition that can cause a blockage
in the intestines (intussusception). From September 1, 1998 - July 7, 1999, more
cases of intussusception following rotavirus vaccine were reported to VAERS than
would have been expected. As a result, in July 1999, the CDC recommended postponing
administration of the rotavirus vaccine until the association with intussusception
could be studied further.
- Two special studies were then launched by the CDC to study this �signal� from
VAERS. Based on these studies, the Advisory Committee on Immunization Practices
(ACIP) withdrew its recommendation of rotavirus vaccine in October 1999. This series
of investigations demonstrated the unique and vital role the Federal government
plays in monitoring vaccine safety to identify and minimize vaccine-related
What Happens When Rare, Adverse Events are Detected?
CDC, National Immunization Program: http://www.cdc.gov/nip
- VAERS reports of life-threatening events, hospitalization and/or extended hospital
stay, life-threatening illnesses, disability and all reports of death, are followed
up individually by a health professional.
- Based on careful review, analysis and further investigation of spontaneous
reports, FDA can initiate various regulatory actions such as changing vaccine labels
or packaging, initiating scientific investigations, distributing safety alerts,
inspecting manufacturers� facilities and records, or withdrawing the vaccine from
- The National Vaccine Injury Compensation Program (VICP) is a Federal program that
helps children who may have experienced rare, serious vaccine side effects. For
details about this program, call (800) 338-2382.
FDA, Center for Biologics Evaluation and Research: http://www.fda.gov/cber
Last updated: August 2001