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.
White blood cell count increased appears in 6,886 VAERS reports across all vaccines. Of these, 422 reports also mentioned death and 4,012 involved hospitalization. The severity rate (deaths + hospitalizations as a percentage of reports) is 64.4%. The top vaccines associated with this symptom are COVID19, PPV, FLU3. Remember: VAERS reports show temporal association, not causation.
White blood cell count increased has been reported 6,886 times in VAERS from 1990 to 2026.
Of these reports, 422 were associated with death (6.13%) and 4,012 involved hospitalization.
The overall serious outcome rate (death or hospitalization) for reports mentioning White blood cell count increased is 64.4%.
This data comes from the Vaccine Adverse Event Reporting System (VAERS), jointly managed by CDC and FDA.