I have heard about the Vaccine Adverse Events Reporting System (VAERS). Does this mean there are more dangers from vaccines than are being reported to VAERS?

Question: I have heard about the Vaccine Adverse Events Reporting System (VAERS). The CDC states: "Limitations of passive surveillance systems include variability in reporting standards, reporter bias and significant under-reporting of events." Does this mean there are more dangers from vaccines than are being reported to VAERS?

Answer: No.

  • VAERS receives only a portion of the total number of events ("numerator") which occur after vaccination. Computing reporting rates from VAERS may be misleading since there is no "denominator" or total doses administered. These limitations make the incidence rates unreliable.
  • A report made to VAERS does not mean that the vaccine caused the event. VAERS is a national system for reporting health problems that happen around the same time of the vaccination. Only some of the reported health conditions are side effects related to vaccines. A certain number of VAERS reports of serious illnesses or death do occur by chance alone among persons who have been recently vaccinated.
  • VAERS reports have many limitations since they often lack important information, such as laboratory results, used to establish a true association with the vaccine. For all serious and other clinically significant events (life-threatening events, hospitalization, permanent disability, death), follow-up with the health care provider and/or the parent or vaccinated individual is conducted in an attempt to collect supplemental information on the reports. Because of the limitations of this type of reporting system, causality is difficult to determine. Regardless of the cause, VAERS is interested in hearing about any health concerns that happen around the time of vaccination. Scientists are not able to identify a problem with a vaccine lot based on VAERS reports alone without scientific analysis of other factors and data. (4, 8)

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1. I have heard vaccines are more dangerous than the diseases they protect against. Isn't it safer for my child to get the disease?
2. Can vaccines cause encephalitis (brain inflammation) and other severe consequences?
3. If vaccines are safe, why has the federal government paid more than $2 billion to children and adults injured by vaccines?
4. Is it possible that aluminum in vaccines could be harmful to normal, healthy babies?
5. Is it true many as 50% of vaccines used in the U.S. contain mercury, which has been linked in the media with autism?
6. I have heard about the Vaccine Adverse Events Reporting System (VAERS). Does this mean there are more dangers from vaccines than are being reported to VAERS?
7. Why should I vaccinate my child when vaccines are not 100% effective and don't always last a lifetime?
8. Is it difficult to get legal exemptions to vaccination for school enrollment?