she had runny nose that lasted about 1.5 weeks; cough; she caught another bug; lost 2 pounds in one day; diarrhea; Initial information regarding an unsolicited valid serious case was received from a consumer/non-health care professional (patient's mother) via Medical Information (Reference number- 00861932) and transmitted to Sanofi on 17-Nov-2021.  This case involves a 12-month-old female patient who had runny nose that lasted about 1.5 weeks (rhinorrhoea), cough, she caught another bug (infection) and had diarrhea (diarrhoea) and lost 2 pounds in one day (weight loss) after receiving INFLUENZA QUADRIVAL A-B VACCINE [FLUZONE QIV].  The patient's medical history, medical treatment(s), vaccination(s) and family history were not provided.  Concomitant medications included MEASLES VACCINE, MUMPS VACCINE, RUBELLA VACCINE in left thigh and AESCULUS HIPPOCASTANUM (VARIVAX) in right thigh for Prophylactic vaccination.  This was the first time ever that the patient received vaccination against influenza.  On 12-Oct-2021, the patient received first 0.5ml total dose of suspect INFLUENZA QUADRIVAL A-B VACCINE (lot: U7328CA and expiry date: 30-Jun-2022) via unknown route in the right thigh for prophylactic vaccination.  Patient's mother was checking all things that could be contributing to her daughter's health status. The consultant checked with Pasteur Customer Service and it was verified that the lot number administered corresponds to FLUZONE QIV SINGLE DOSE VIAL.  The consultant checked with Sanofi Pasteur Customer Service, who looked up the lot number provided and found that it corresponds to FLUZONE QIV from the single dose vial.  On an unknown date, patient's mom took her daughter to the hospital because a week after vaccination, patient had serious runny nose that lasted about 1.5 weeks (rhinorrhoea) which then developed into a cough. The cough wakes her every night and is ongoing.  On an unknown date, at the hospital, serious pneumonia was ruled out with laboratory test of chest x-ray.  On an unknown date, in between, when patient was already sick, the patient's mom believes patient caught another bug (infection) and patient had severe diarrhea (diarrhoea). Patient also reportedly lost 2 pounds in one day (weight decreased).   These all events were assessed as medically significant.  It was also reported that caller requesting information regarding this year's flu vaccine. Caller wants to know what the dose is for a 1-year-old. Caller not sure which flu vaccine would be administered to child. The caller's daughter received a dose of a flu vaccine on 12Oct2021. She has the lot number, but not the name of the vaccine. Patient's mom is unsure if the appropriate dose was given and wants to check. The reason she is unsure is that in the past, when her older daughter received flu vaccine, it was in a special syringe that indicated the dose was a child's dose. This time, for her younger daughter, the syringe did not look the same.  It was not reported if the patient received a corrective treatment for the events.  At time of reporting, the outcome was resolved for rhinorrhea, unknown for infection and not resolved for rest of the events.; Sender's Comments: This case concerns 12-month-old female patient who had runny nose that lasted about 1.5 weeks (rhinorrhoea), cough, she caught another bug (infection) and had diarrhea (diarrhoea) and lost 2 pounds in one day (weight loss) after vaccination with FLUZONE QIV. The time to onset is compatible Additional information regarding patient's past medical history, condition at the time of vaccination, lab data excluding other predisposing etiologies would be needed for complete assessment of the case. Based upon the reported information, the role of the vaccine cannot be assessed.