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Report #2881172

Received Jan 9, 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
Unknown
Age
1 yrs
State
TX
Recovered
Unknown
Vaccinated
Dec 9, 2025
Onset
Dec 9, 2025
Days to onset
0
Hospital days
—

Vaccines (2)

TypeNameManufacturerDoseLotRoute / Site
MMRVMEASLES + MUMPS + RUBELLA + VARICELLA (PROQUAD)MERCK & CO. INC.UNKZ012063—
VARCELVARICELLA (VARIVAX)MERCK & CO. INC.UNKZ008873—

Symptoms (2)

Extra dose administeredNo adverse event

Symptom narrative

No additional AE/ No PQC reported.; Medical Assistant calling to report inadvertently administering PROQUAD and VARIVAX to a 12 month old patient instead of MMRII and VARIVAX. Caller stated patient has not reported any symptoms. Permission to contact HCP was granted. no additional info; This spontaneous report was received from a Other health professional and refers to a(n) 1-year-old patient of unknown gender. The patient's medical history, concurrent conditions and concomitant therapies were not reported. On 09-Dec-2025, the patient was inadvertently vaccinated with a dose of Measles, Mumps, Rubella and Varicella (Oka-Merck) Virus Vaccine Live (PROQUAD), lot #Z012063, expiration date: 18-Jan-2027 (anatomical location and administration route were not reported) and with a dose of Varicella Virus Vaccine Live (Oka-Merck) (VARIVAX), lot #Z008873, expiration date: 14-May-2027, (anatomical location and administration route were not reported) both doses as prophylaxis. The patient was vaccinated with Measles, Mumps, Rubella and Varicella (Oka-Merck) Virus Vaccine Live (PROQUAD) and Varicella Virus Vaccine Live (Oka-Merck) (VARIVAX) instead of receiving Measles, Mumps, and Rubella (Wistar RA 27-3) (M-M-R II) and Varicella Virus Vaccine Live (Oka-Merck) (VARIVAX) (Interchange of vaccine products). The reporter stated that the patient has not reported any symptoms. No additional adverse events were reported.

Other medications

sterile diluent Solution for injection