⚠️
Important: VAERS reports alone cannot determine if a vaccine caused an adverse event. Reports may contain incomplete, inaccurate, or unverified information. Correlation does not equal causation.
Immunisation reaction
2,700 total reports11.0% serious outcomes
Share
2,700
Total Reports
30
Deaths
266
Hospitalizations
11
Severity Rate
% serious outcomes
About Immunisation reaction Reports
Immunisation reaction has been reported 2,700 times in VAERS from 1990 to 2026.
Of these reports, 30 were associated with death (1.11%) and 266 involved hospitalization.
The overall serious outcome rate (death or hospitalization) for reports mentioning Immunisation reaction is 11.0%.
Understanding Immunisation reaction in VAERS
•Temporal association only: These reports show Immunisation reaction occurred after vaccination, not necessarily because of vaccination.
•Background rates matter: Many symptoms occur naturally at baseline rates in the population, unrelated to vaccination.
•Reporting variability: Medical terminology may be used differently by various healthcare providers and over time.
•Investigation needed: High-frequency reports may trigger further epidemiological studies to determine causation.
What This Data Shows
Most Associated Vaccines: The vaccines most frequently mentioned in reports with Immunisation reaction. This may reflect usage patterns, not causation.
Severity Patterns: The percentage of reports that involve serious outcomes can help prioritize safety investigations.
Reporting Trends: Changes in reporting frequency over time may reflect increased awareness, media attention, or actual safety signals.
Most Associated Vaccines
1. COVID192,191
2. COVID19-2251
3. UNK184
4. VARZOS114
5. FLU486
6. FLU374
7. PNC2072
8. MMR58
9. FLUX55
10. PPV54
Quick Facts
Reports:2,700
Deaths:30
Hospitalizations:266
Mortality Rate:1.11%
Severity Rate:11.0%
Related Analysis
Explore Further
Data Source
This data comes from the Vaccine Adverse Event Reporting System (VAERS), jointly managed by CDC and FDA.