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

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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. Influenza, Seasonal
  4. Complement factor normal
Influenza, Seasonal×Complement factor normal

Complement factor normal Reports for Influenza, Seasonal

#674 most reported symptom for this vaccine

22
Reports
0
Deaths
14
Hospitalizations
0
Mortality Rate
%
63.6
Hosp. Rate
%

Complement factor normal and Influenza, Seasonal

Complement factor normal has been reported 22 times in association with Influenza, Seasonal vaccination in VAERS. This represents 0.1% of all 32,816 reports for this vaccine.

Among these reports, 0 mentioned death (0.00%) and 14 involved hospitalization (63.6%).

Complement factor normal is the #674 most frequently reported symptom for Influenza, Seasonal out of 2462 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 22 reports of Complement factor normal after Influenza, Seasonal 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 Complement factor normal occurred after vaccination, not that the vaccine caused it.
•Background rates: Complement factor normal 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

Muscle contractions involuntary22 reportsVomiting projectile22 reportsInfluenza B virus test22 reportsParanasal sinus discomfort22 reports

Quick Facts

Reports:22
Deaths:0
Hospitalizations:14
% of Vaccine:0.1%
Rank:#674 of 2462

Related Pages

Influenza, Seasonal OverviewComplement factor normal (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.