CDC Study Finds No Pattern Suggesting Vaccines Contributed To Or Caused Deaths

Google+ Interview with:
Dr. Pedro Moro, MD, MPH

Immunization Safety Office
Division of Healthcare Quality Promotion
Centers for Disease Control and Prevention
Atlanta, GA 3033

Medical Research: What is the background for this study? What are the main findings?

Response: The Vaccine Adverse Event Reporting System (VAERS) is a US national vaccine safety surveillance system, co-administered by the Centers for Disease Control and Prevention (CDC) and the US Food and Drug Administration (FDA). VAERS accepts reports of adverse events (possible side effects) following vaccination. Anyone can submit a report to VAERS.

The study team searched VAERS for US reports of death after any vaccination from 7/1/1997 to 12/31/2013.

During that time period, VAERS received 2,149 death reports, with most (68.4%) occurring in children. Among children, the most common causes of death were:

o   sudden infant death syndrome (44%)

o   asphyxia, or lack of oxygen to the brain (6%)

o   septicemia, or blood poisoning from a bacterial infection (5%)

o   pneumonia (5%)

Among adults, the most common causes of death were:

o   diseases of the circulatory system (47%)

o   diseases of the respiratory system (15%)

o   infections and parasitic diseases (12%)

o   tumors (4%)

The main causes of death seen in VAERS reports were consistent with the most common causes of death in the US population. When studied separately, none of these causes of death have found to be related to vaccines. This finding is reassuring, and consistent with previous research on vaccine safety.

Medical Research: What should clinicians and patients take away from your report?

Response: First and foremost, vaccines are safe, effective, and save lives. There are strong systems in place to make sure that vaccines are safe, including VAERS.

The primary goal of VAERS is to detect possible safety problems that may be related to vaccination. If, after an initial evaluation, CDC and FDA scientists determine that a potential safety issue requires further investigation, former studies can be conducted using other, more robust data sources. However, VAERS data do have limitations. One of the limitations is that a report to VAERS does not necessarily mean that the vaccine caused the adverse event.

In this study, researchers reviewed reports of death after vaccination and found no patterns which would indicate that vaccines caused or contributed to the deaths.

Medical Research: What recommendations do you have for future research as a result of this study?

Response: CDC will continue to monitor and assess death reports to VAERS to ensure public confidence in the immunization program.


Pedro L. Moro, Jorge Arana, Maria Cano, Paige Lewis, and Tom T. Shimabukuro

Deaths reported to the Vaccine Adverse Event Reporting System (VAERS), United States, 1997-2013 Clin Infect Dis. first published online May 28, 2015 doi:10.1093/cid/civ423

Dr. Pedro Moro, MD, MPH, Immunization Safety Office, Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention,  Atlanta, GA 3033 (2015). CDC Study Finds No Pattern Suggesting Vaccines Contributed To Or Caused Deaths