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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. White blood cell count increased
FLU(H1N1)×White blood cell count increased

White blood cell count increased Reports for FLU(H1N1)

#148 most reported symptom for this vaccine

49
Reports
1
Deaths
28
Hospitalizations
2.04
Mortality Rate
%
57.1
Hosp. Rate
%

White blood cell count increased and FLU(H1N1)

White blood cell count increased has been reported 49 times in association with FLU(H1N1) vaccination in VAERS.

Among these reports, 1 mentioned death (2.04%) and 28 involved hospitalization (57.1%).

White blood cell count increased is the #148 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 49 reports of White blood cell count increased after FLU(H1N1) vaccination may seem alarming, but context is critical.

The mortality rate of 2.04% warrants monitoring, though VAERS deaths represent temporal associations, not confirmed causal links.

Important Context

•Association, not causation: These reports show White blood cell count increased occurred after vaccination, not that the vaccine caused it.
•Background rates: White blood cell count increased 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

Blood test normal50 reportsTenderness50 reportsImpaired work ability49 reportsHerpes zoster47 reports

Quick Facts

Reports:49
Deaths:1
Hospitalizations:28
% of Vaccine:—%
Rank:#148 of 993

Related Pages

FLU(H1N1) OverviewWhite blood cell count increased (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.