Received Nov 25, 2025
| Type | Name | Manufacturer | Dose | Lot | Route / Site |
|---|---|---|---|---|---|
| FLU3 | INFLUENZA (SEASONAL) (FLUZONE HIGH-DOSE) | SANOFI PASTEUR | UNK | — | OT |
lack of intended effect, had influenza A 6 weeks later; got sick at home, took a home test and was influenza A+ positive; Initial information received on 10-Nov-2025 regarding an unsolicited valid serious case received from a patient. This case involves Elderly female patient who experienced lack of intended effect, had influenza a 6 weeks later and got sick at home, took a home test and was influenza A+ positive after receiving Influenza Usp Trival A-B High Dose Subvirion Vaccine [Fluzone HD]. The patient's past medical history, medical treatment(s), vaccination(s) and family history were not provided. On an unknown date in January 2025, the patient received a dose of suspect Influenza Usp Trival A-B High Dose Subvirion Vaccine (strength, expiry date and lot number not reported) via unknown route in unknown administration site as flu vaccination (immunization). On an unknown date in 2025, the patient developed lack of intended effect, had influenza a 6 weeks later (vaccination failure) (unknown latency) and took a home test and was influenza a+ positive (influenza) (latency: 6 weeks). Relevant laboratory test results included: Influenza A virus test - In 2025: Positive Action taken: not applicable. A Patient took baloxavir for influenza, felt less bad 12-16 hours later (later got sick at home) and was not reported for other event. At time of reporting, the outcome was Unknown for the event vaccination failure and was Recovered / Resolved on an unknown date in 2025 for the event influenza. This event (vaccination failure) was assessed as medically significant.; Sender's Comments: Sanofi company comment dated on 17-Nov-2025: This case involves Elderly female patient who experienced lack of intended effect, had influenza a 6 weeks later and got sick at home, took a home test and was influenza A+ positive after receiving Influenza Usp Trival A-B High Dose Subvirion Vaccine [Fluzone HD]. Lack of information regarding medical history or family history, preexisting and concurrent medical condition and concomitant medication laboratory investigations excluding other predisposing etiologies precludes the complete assessment of the case. Based upon the reported information, the role of a vaccine cannot be assessed.
Test Date: 2025; Test Name: home test; Test Result: Positive