Skip to main content
VaccineWatch
VaccinesSymptomsStatesAnalysisToolsDashboardCompare

VaccineWatch

Transparent access to VAERS data for informed decision-making. We present the data as-is, with appropriate context and disclaimers.

Explore Data

  • Vaccines
  • Symptoms
  • Manufacturers
  • States
  • Dashboard
  • Compare Tool
  • Search

Deep Dives

  • The Denominator Problem
  • Onset Timing
  • Lot Number Analysis
  • COVID Impact
  • Myocarditis
  • Death Reports
  • Interactive Tools
  • Reporting Rate Calculator
  • Signal Detection
  • All 23 Articles →

Resources

  • About
  • Methodology
  • FAQ
  • Glossary
  • Side Effects Guide
  • Vaccine Schedule
  • Vaccine Safety
  • Safety Timeline
  • Adverse Events
  • Is VAERS Reliable?
  • Myocarditis
  • Guillain-Barré
  • Allergic Reactions
  • Report an Event
  • Disclaimer
  • VAERS Official Site ↗

Sister Sites

  • OpenMedicaid
  • OpenFeds
  • OpenImmigration
  • OpenSubsidies
  • OpenSpending
  • OpenMedicare
  • OpenLobby
  • WarCosts
  • OpenPrescriber
  • TheDataProject.ai

Data source: VAERS (Vaccine Adverse Event Reporting System)

Data through 2026 · Updated quarterly

Built by TheDataProject.ai · © 2026 VaccineWatch

Important: VAERS accepts reports of adverse events following vaccination. For any given report, there is no certainty that the reported event was caused by the vaccine. Reports may contain information that is incomplete, inaccurate, coincidental, or unverifiable. Most reports to VAERS are voluntary, which means they are subject to biases. This data cannot be used to determine if vaccines cause or contribute to adverse events.

⚠️

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.

  1. Home
  2. Vaccines
  3. FLU(H1N1)
  4. Injection site oedema
FLU(H1N1)×Injection site oedema

Injection site oedema Reports for FLU(H1N1)

#418 most reported symptom for this vaccine

10
Reports
0
Deaths
0
Hospitalizations
0
Mortality Rate
%
0
Hosp. Rate
%

Injection site oedema and FLU(H1N1)

Injection site oedema has been reported 10 times in association with FLU(H1N1) vaccination in VAERS.

Among these reports, 0 mentioned death (0.00%) and 0 involved hospitalization (0.0%).

Injection site oedema is the #418 most frequently reported symptom for FLU(H1N1) out of 993 total symptoms.

Disclaimer: VAERS reports describe events that occurred after vaccination but do not establish that the vaccine caused the event. Many reported symptoms may be coincidental or related to underlying conditions.

What This Means

Seeing 10 reports of Injection site oedema after FLU(H1N1) vaccination may seem alarming, but context is critical.

The mortality rate among these reports is very low at 0.00%, suggesting most cases are non-fatal.

Important Context

•Association, not causation: These reports show Injection site oedema occurred after vaccination, not that the vaccine caused it.
•Background rates: Injection site oedema may occur naturally at baseline rates in the population, unrelated to vaccination.
•Anyone can report: VAERS accepts reports from anyone — patients, parents, healthcare providers — without requiring medical verification.
•Denominator missing: VAERS counts reports, not rates per dose. Without knowing how many doses were given, raw counts can be misleading. Learn more →

Similarly Ranked Symptoms

Anaemia10 reportsType 1 diabetes mellitus10 reportsBody temperature decreased10 reportsDrug screen negative10 reports

Quick Facts

Reports:10
Deaths:0
Hospitalizations:0
% of Vaccine:—%
Rank:#418 of 993

Related Pages

FLU(H1N1) OverviewInjection site oedema (All Vaccines)Why Raw Numbers MisleadTop Symptoms Analysis

Data Source

This data comes from the Vaccine Adverse Event Reporting System (VAERS), jointly managed by CDC and FDA.