Age: 1.0
Sex: U
Vaccine: VARCEL
Symptoms: Device connection issue, Syringe issue, Underdose
Clinical narrative: No additional AE/PQC; I know the patient didn't get the full dose of VARIVAX, because it seemed like over 1/4th of the syringe shot out while I was pushing the plunger down during administration; I noticed that liquid was shooting out of the syringe where the needle screws into the hub (Luer Lock) of the syringe.; but as I was screwing on the needle, it did feel a little loose; As I was administering a dose of VARIVAX to a patient that was prepared and administered using the STERILE DILUENT PFS that is supplied with the vaccine, I noticed that liquid was shooting out of the syringe where the needle screws into the hub (Luer; This spontaneous report was received from a medical assistant, referring to a 1-year-old patient of unknown gender. The patient's pertinent medical history, drug reactions/allergies, concurrent condition and concomitant medication were not provided.  On 24-JUN-2024, the patient was vaccinated with varicella virus vaccine live (oka/merck) (VARIVAX), 0.5 milliliter injection, over 1/4th dose, lot #Y002062 has been verified to be a valid lot number, expiration date was reported and validated as 09-JAN-2026, administered for prophylaxis (route of administration and exact dose were not provided); and sterile diluent (BAXTER STERILE DILUENT) (2 dose series), 0.7 milliliter solution for injection/infusion, over 1/4th dose, once, lot #1973250, expiration date: 11-FEB-2026 (route of administration, exact dose and indication were not provided).  On that day, when the reporter was administering a dose of varicella virus vaccine live (oka/merck) (VARIVAX) to the patient that was prepared and administered using the sterile diluent (BAXTER STERILE DILUENT) that was supplied with the vaccine, liquid was shooting out of the syringe where the needle screws into the hub (Luer Lock) of the syringe (device leakage) (poor quality device used). The reporter didn't notice any defects of the sterile diluent (BAXTER STERILE DILUENT) or the varicella virus vaccine live (oka/merck) (VARIVAX) vial when the reporter was preparing the dose for administration, but as the reporter was screwing on the needle, it did feel a little loose, so the reporter tightened the needle with two more rotations and it felt secure and stable (device connection issue). There wasn't anything visibly wrong or defective with the syringe before the reporter administered the dose of virus vaccine live (oka/merck) (VARIVAX), and the patient did not have any reactions to the virus vaccine live (oka/merck) (VARIVAX) that was administered.The patient didn't get the full dose of virus vaccine live (oka/merck) (VARIVAX), because it seemed like over 1/4th of the syringe shot out while the reporter was pushing the plunger down during administration (accidental underdose). The reporter threw out the sterile diluent (BAXTER STERILE DILUENT) and the virus vaccine live (oka/merck) (VARIVAX) after this event occurred and no one was harmed during this event. Medical assistant confirmed there were no issues with the virus vaccine live (oka/merck) (VARIVAX) vial and no defects noticed during reconstitution of the virus vaccine live (oka/merck) (VARIVAX) dose. No pictures were taken of the sterile diluent (BAXTER STERILE DILUENT) prior to disposing of the product based on their facility's policies and procedures. Therefore, neither the sterile diluent (BAXTER STERILE DILUENT) or the virus vaccine live (oka/merck) (VARIVAX) vial were available for retrieval based on the details above.  No additional information was provided regarding this report. No additional adverse event (AE)/additional product quality concern (PQC) was reported (no adverse event). It was also reported: no the syringe needle was attached or being attached to the syringe tip when the leaking occurred; the needle was not supplied by the company; there was difficulty trying to attach the needle; the size and gauge of the needle: 25g, 5/8 inch, Lot #CJCJ08-01, Expiry Date 31-JUL-2025; the leaking occurred where the needles screwed into the threading on the lucer lock; the plunger rod was being pushed forward.