VAERS Explorer
Back to explore

Report #2890264

Received Mar 23, 2026

A note on interpretation. VAERS reports are unverified and may be incomplete or coincidental. A report does not establish that a vaccine caused an event, and counts should not be used to calculate incidence or infer causation. Full disclaimer

Overview

Sex
Male
Age
Age unknown
State
Recovered
Unknown
Vaccinated
Oct 1, 2025
Onset
Mar 3, 2026
Days to onset
153
Hospital days

Vaccines (1)

TypeNameManufacturerDoseLotRoute / Site
UNKVACCINE NOT SPECIFIED (NO BRAND NAME)UNKNOWN MANUFACTURERUNK

Symptoms (4)

InfluenzaInfluenza B virus test positivePneumonia viralVaccination failure

Symptom narrative

Vaccination failure; tested positive for B-strain Flu; showing symptoms of viral pneumonia; Initial information received on 05-Mar-2026 regarding an unsolicited valid serious case received from a consumer (non-healthcare professional). This case involves a male patient of unknown age who had tested positive for B-strain flu after receiving influenza trivalent recombinant vaccine [FLUBLOK TIV]. The patient's past medical history, medical treatment(s), vaccination(s), and family history were not provided. In Oct-2025, the patient received a 1X dose once of influenza trivalent recombinant vaccine [FLUBLOK TIV] solution for injection (batch/lot number and expiry date: unknown) (strength: unknown) via unknown route in an unknown administration site for influenza. A Sanofi employee stated he was speaking with a co-worker (patient) and they mentioned receiving a FLUBLOK back in Oct-2025. On 03-Mar-2026, the patient tested positive for B-strain flu (Influenza, onset: 03-Mar-2026, latency: approximately 5 months) and he was showing symptoms of viral pneumonia (Pneumonia viral, onset: 2026, latency: unknown). The patient experienced vaccination failure (Vaccination failure, onset: unknown, latency: unknown). Information regarding batch number and expiration date corresponding to the one at time of event occurrence was requested. Relevant laboratory test results included: Influenza B virus test - On 03-Mar-2026 with positive result; tested positive for B-strain flu. Action taken: Not applicable. Corrective treatment: Not reported. Event outcome: Unknown for influenza. Seriousness criteria: Medically significant for influenza

Medical history

Comments: NONE

Lab data

Test Date: 20260303; Test Name: Influenza B virus test; Result Unstructured Data: tested positive for B-strain Flu