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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.

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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 induration
FLU(H1N1)×Injection site induration

Injection site induration Reports for FLU(H1N1)

#133 most reported symptom for this vaccine

55
Reports
0
Deaths
3
Hospitalizations
0
Mortality Rate
%
5.5
Hosp. Rate
%

Injection site induration and FLU(H1N1)

Injection site induration has been reported 55 times in association with FLU(H1N1) vaccination in VAERS.

Among these reports, 0 mentioned death (0.00%) and 3 involved hospitalization (5.5%).

Injection site induration is the #133 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 55 reports of Injection site induration 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 induration occurred after vaccination, not that the vaccine caused it.
•Background rates: Injection site induration 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

Vaccination complication56 reportsDysstasia56 reportsDeath55 reportsIntra-uterine death54 reports

Quick Facts

Reports:55
Deaths:0
Hospitalizations:3
% of Vaccine:—%
Rank:#133 of 993

Related Pages

FLU(H1N1) OverviewInjection site induration (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.