The Importance of Vaccine Safety Programs
Vaccination is among the most significant public health success stories of all time. However, like any pharmaceutical product, no vaccine is completely safe or completely effective. While almost all known vaccine adverse events are minor and self-limited, some vaccines have been associated with very rare but serious health effects. The following key considerations underscore the need for an active and ongoing vaccine safety program.
Decreases in Disease Risks
Today, vaccine-preventable diseases are at or near record lows. Many people no longer see reminders of the severity and potential life-threatening complications of these diseases. Recent outbreaks of vaccine–preventable diseases show that even vaccinated people are at risk for disease if there is not adequate vaccine coverage in the population. Parents and providers in the United States may be more likely to know someone who has experienced an adverse event following immunization than they are to know someone who has experienced a vaccine-preventable disease. The success of vaccination has led to increased public attention on potential health risks associated with vaccines.
Public Confidence
Maintaining public confidence in immunizations is critical for preventing a decline in vaccination rates that can result in outbreaks of disease. While the majority of parents understand the benefits of immunization and have their children vaccinated, some have concerns about the safety of vaccines.
Public concerns about the safety of whole-cell pertussis vaccine in the 1980s resulted in decreased vaccine coverage and the return of epidemic disease in Japan, Sweden, United Kingdom, and several other countries. Around the same time in the United States, similar concerns led to increases both in the number of lawsuits against manufacturers and the price of vaccines, and to a decrease in the number of manufacturers willing to produce vaccines. This led to the National Childhood Vaccine Injury Act which is discussed in this chapter.
Despite high national vaccination coverage rates, there are areas of low coverage that allow outbreaks of vaccine-preventable diseases to occur, many due to concerns about vaccine safety leading parents to refuse or delay their children’s immunizations. For example, during 2008, more measles cases were reported than in any year since 1997. More than 90% of those infected had not been vaccinated, or their vaccination status was unknown. In California during January 1- June 30, 2010, 1,337 pertussis cases were reported to the California Department of Public Health, a 418% increase from the 258 cases reported during the same period in 2009. Providing accurate and timely vaccine safety information to healthcare providers, parents, and the general population has a positive effect on vaccine uptake and is a high priority for CDC. Close monitoring and timely assessment of suspected vaccine adverse events can distinguish true vaccine reactions from coincidental unrelated events and help to maintain public confidence in immunizations.
A higher standard of safety is generally expected of vaccines than of other medical interventions because in contrast to most pharmaceutical products, which are administered to ill persons for curative purposes, vaccines are generally given to healthy persons to prevent disease. Public tolerance of adverse reactions related to products given to healthy persons, especially healthy infants and children, is substantially lower than for reactions to products administered to persons who are already sick. This lower tolerance of risk for vaccines translates into a need to investigate the possible causes of very rare adverse events following vaccinations.
Adding to public concern about vaccines is the fact that immunization is mandated by many state and local school entry requirements. Because of this widespread use, safety problems with vaccines can have a potential impact on large numbers of persons. The importance of ensuring the safety of a relatively universal human-directed “exposure” like immunizations is the basis for strict regulatory control of vaccines in the United States by the Food and Drug Administration (FDA).
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