Received Apr 15, 2026
| Type | Name | Manufacturer | Dose | Lot | Route / Site |
|---|---|---|---|---|---|
| YF | YELLOW FEVER (YF-VAX) | SANOFI PASTEUR | UNK | UK211AA | SC / LA |
administering YF-VAX with the incorrect diluent, with no reproted adverse event; Initial information received on 23-Mar-2026 regarding an unsolicited valid non-serious case received from a healthcare professional. This case involves a 21-year-old female patient who experienced administering yellow fever vaccine (YF-VAX) with the incorrect diluent, with no reported adverse event. The patient's past medical history, past drugs, vaccination(s), family history were not provided. Concomitant medication(s) included tozinameran (Covid Vaccine (Pfizer)), meningococcal vaccine B rfHbp/NadA/NHBA OMV (Bexsero), typhoid vaccine polysacch Vi (Typhim VI), and influenza vaccine (Fluzone NP). On 04-Mar-2026, the patient received yellow fever vaccine solution for injection (strength: standard) as 0.5 mL once subcutaneous in left arm for immunization was given with the wrong diluent (product preparation error, onset: 04-Mar-2026 and latency: same day) (batch: UK211AA, expiry: 31-Jul-2026). It was not the diluent that came with the product. One of the staff noticed the miscount between the normal saline and YF-VAX diluent so, they believed that a staff pulled the sterile water diluent for varicella and other things that was on the table. She said that three patients received YF-VAX in the timeframe of miscount, but they were not sure which one among them got the wrong diluent. Only one patient was administered with the wrong diluent. She would like to get information on the safety concerns and immunity if they need to be revaccinated. She asked what next steps they should take. She then added that they might revaccinate all three patients since they were not sure which one received the wrong diluent. Action taken with yellow fever vaccine was not applicable. This suspected adverse reaction report is submitted and classified as a medication error solely and exclusively to ensure the marketing authorization holder's compliance with the requirements set out in the Directive 2001/83/EC and Module VI of the Good Pharmacovigilance Practices. The classification as a medical error is in no way intended, nor should it be interpreted or construed as an allegation or claim made by the marketing authorization holder that any third party has contributed to or is to be held liable for the occurrence of this medication error.
Comments: NONE
Pfizer BioNTech COVID-19 vaccine; Bexsero; Typhim vi; Fluzone