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.
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VAERS Database
The Vaccine Adverse Event Reporting System (VAERS) is the nation's early warning system for vaccine safety. We've processed all 1,983,260 reports into searchable, contextualized data — so you don't have to navigate the clunky CDC interface.
1,983,260
Total Reports
104
Vaccines
1,000
Symptoms
35
Years (1990–2026)
What Is VAERS?
VAERS (Vaccine Adverse Event Reporting System) is a national passive surveillance system co-managed by the CDC and FDA. Created in 1990 under the National Childhood Vaccine Injury Act, VAERS collects reports of adverse health events that occur after vaccination.
Key points about VAERS:
Anyone can report: Patients, parents, healthcare providers, and manufacturers can all submit reports
Reports are unverified: VAERS does not investigate or confirm that vaccines caused the reported events
Passive system: Relies on voluntary reporting (except for certain mandated events)
Purpose: Detect potential safety signals that warrant further investigation — not to prove causation
How to Use VAERS Data
VAERS data is useful for:
Identifying unusual patterns that might indicate a safety signal
Monitoring known adverse events across different vaccines
Comparing reporting patterns between vaccines or time periods
Understanding what types of events are being reported
VAERS data should NOT be used to:
Determine if a vaccine caused a specific adverse event
Calculate the actual risk of an adverse event from vaccination
Compare the safety of different vaccines without controlling for confounding factors
Make personal vaccination decisions without consulting a healthcare provider
VAERS vs CDC WONDER
The official way to access VAERS data is through CDC WONDER, which provides query-based access but has a steep learning curve and limited visualization. VaccineWatch processes the same raw data files but presents them with:
Pre-built pages for every vaccine, symptom, manufacturer, and state
Interactive charts and comparison tools
Cross-referenced data (vaccine-symptom, vaccine-year, state-vaccine combinations)
Context and disclaimers to help interpret the data correctly
VaccineWatch processes the complete VAERS dataset, which consists of three CSV files per year (VAERSDATA, VAERSVAX, VAERSSYMPTOMS) going back to 1990. Our pipeline:
Download: Complete VAERS CSV files from the CDC (updated quarterly)
Parse: Proper CSV parsing to handle free-text fields with commas and quotes
Process: Extract and compute fields: onset timing, dose series, lot data, recovery status
Cross-reference: Generate vaccine-symptom, vaccine-year, state-vaccine, and manufacturer combinations
Aggregate: Compute statistics, rates, and rankings
Publish: Static JSON files served through Next.js with on-demand rendering
The result: 85,000+ unique pages covering every meaningful combination of vaccine, symptom, year, state, and manufacturer in the VAERS database.
Data Coverage
Reports: 1,983,260 total (1990–2026)
Deaths reported: 27,732
Hospitalizations: 143,653
Vaccines: 104 unique types
Symptoms: 1,000 unique types
States/territories: 117
Analysis articles: 23 in-depth analyses
Interactive tools: 13 specialized data tools
Understanding the Data
Before diving into the data, read these critical context articles: