# Presentation: 681330

## Vaccine Safety

**Epidemiology and Prevention of Vaccine-Preventable Diseases**
**National Center for Immunization and Respiratory Diseases**
**Centers for Disease Control and Prevention**

**Revised March 2008**

## Importance of Vaccine Safety

**Decreases in disease risks and increased attention on vaccine risks**
**Public confidence in vaccine safety is critical**
**higher standard of safety is expected of vaccines**
**vaccinees generally healthy ****(vs. ill for drugs)**
**lower risk tolerance = need to search for rare reactions**
**vaccination universally recommended and mandated**** **

## Comparison of Pre-Vaccine and Current Reported Morbidity of Vaccine-Preventable Diseases andVaccine Adverse Events, United States

***   Baseline 20****th**** century annual morbidity**
**+  Estimated because no national reporting existed in the pre-vaccine era**
****  Source: *****MMWR***** 2007;56(33):851-64**

**Comparison of Pre-Vaccine and Current Reported Morbidity of Vaccine-Preventable Diseases and****Vaccine Adverse Events, United States**

**Total                             1,064,854                22,532                 97.9**

**Vaccine Adverse Events      N/A               15,484                  +++**

**Notes:**
Today, vaccine-preventable diseases are at or near record lows.  By virtue of their absence, these diseases are no longer a reminder of the benefits of vaccination.  At the same time, approximately 10,000 cases of adverse events following vaccination are reported in the U.S. each year (these include both true adverse reactions and events that coincidentally occur after vaccination).  This number exceeds the current reported incidence of vaccine-preventable childhood diseases.  As a result, parents and providers in the U.S. are more likely to know someone who has experienced an adverse event following immunization than they are to know someone who has experienced a reportable vaccine-preventable disease.

## Importance of Vaccine Safety

**Ongoing safety monitoring needed for the development of sound policies and recommendations**

## Prelicensure Vaccine Safety Studies

**Laboratory**
**Animals**
**Humans**

## Prelicensure Human Studies

**Phases I, II, III trials**
**Common reactions are identified**
**Vaccines are tested in thousands of persons before being licensed and allowed on the market**

## Postlicensure Surveillance

**Identify rare reactions**
**Monitor increases in known reactions**
**Identify risk factors for reactions**
**Identify vaccine lots with unusual  rates or types of events**
**Identify signals**

## Postlicensure Vaccine Safety Activities

**Phase IV Trials **
**~10,000 participants**
**better but still limited**
**Large-Linked Databases**
**Clinical Immunization Safety Assessment Network**

## Vaccine Adverse Event Reporting System (VAERS) 

**National reporting system**
**Jointly administered by CDC ****and FDA**
**Passive (depends on healthcare providers and others to report)**
**Receives ~15,000 reports per year**

## Vaccine Adverse Event Reporting System (VAERS) 

**Detects**
**new or rare events**
**increases in rates of known side effects**
**patient risk factors **
**Additional studies required to confirm VAERS signals**
**Not all reports of adverse events are causally related to vaccine**

## Adverse Event Classification

**Vaccine-induced**
**Vaccine-potentiated**
**Programmatic error**
**Coincidental**

## Vaccine Safety Datalink (VSD)

**Large-linked database**
**Links vaccination and health records**
**“****Active surveillance”**
**8 HMOs**
** ****~2% of the U.S. population**
**Powerful tool for monitoring vaccine safety**

## Clinical Immunization Safety Assessment (CISA) Network

**Improve understanding of vaccine safety issues at individual level**
**Evaluate persons who experience adverse health events**
**Gain better understanding of events**
**Develop protocols for healthcare providers**

## Vaccine Injury Compensation Program (VICP)

**Established by National Childhood Vaccine Injury Act (1986)**
**“****No fault” program**
**Covers all routinely ****recommended childhood ****vaccines**
**Vaccine Injury Table **

## The Provider’s Role

**Immunization providers can help to ensure the safety and efficacy of vaccines through proper:**
**vaccine storage and administration**
**timing and spacing of vaccine doses**
**observation of contraindications and precautions**

## The Provider’s Role

**Immunization providers can help to ensure the safety and efficacy of vaccines through proper:**
**management of vaccine side effects**
**reporting of suspected side effects to VAERS**
**vaccine benefit and risk communication**

## Contraindication

**   ****A condition in a recipient that increases the chance of a serious adverse reaction**

## Precaution

**  ****A condition in a recipient that might **
**Increase the chance or severity of an adverse reaction, or**
**Compromise the ability of the vaccine to produce immunity**

## Invalid Contraindications to Vaccination

**Minor illness**
**Mild/moderate local reaction or fever following a prior dose**
**Antimicrobial therapy**
**Disease exposure or convalescence**
**Pregnancy or immunosuppression in the household**
**Premature birth**
**Breastfeeding**
**Allergies to products not in vaccine**
**Family history (unrelated to immunosuppression) **

## Benefit and Risk Communication

**Opportunities for questions should ****be provided before each vaccination**
**Vaccine Information Statements (VISs)**
**must be provided before each dose ****of vaccine**
**public and private providers**
**available in multiple languages**

## CDC Vaccines and ImmunizationContact Information

**Telephone      800.CDC.INFO**** **
**Email****	****	****   nipinfo@cdc.gov**** **
**Website****	****   www.cdc.gov/vaccines**