route of administered reported as IM; have been noticing children that received the MMRII have experienced redness, swelling and sometimes hives at injection site that occur immediately after administration, and up to 15 minutes after administration; have been noticing children that received the MMRII have experienced redness, swelling and sometimes hives at injection site that occur immediately after administration, and up to 15 minutes after administration; have been noticing children that received the MMRII have experienced redness, swelling and sometimes hives at injection site that occur immediately after administration, and up to 15 minutes after administration; This non-valid spontaneous report was received from a medical assistant who is also the clinical supervisor via a company representative and referred to unspecified numbers of children. The patients' concurrent conditions, concomitant therapies or medical history were not reported.  The reporter stated since "mid-February" in 2021, they had been used that batch of measles, mumps, and rubella (wistar ra 27-3) virus vaccine, live (M-M-R II) for 12-month well visits in her facility, and the patients had been vaccinated with measles, mumps, and rubella (wistar ra 27-3) virus vaccine, live(M-M-R II) (0.5 milliliter, lot # T006166 has been verified to be a valid lot number, expiration date 19-FEB-2022, therapy type rHA; formulation and concentration were not reported), intramuscularly (IM) (incorrect route of product administration) for prophylaxis.  The reporter and her fellow staff have noticed an increase in site reactions in numerous children after receiving measles, mumps, and rubella (wistar ra 27-3) virus vaccine, live (M-M-R II). The patients had experienced redness, swelling and sometimes hives at injection site that occur immediately after administration, and up to 15 minutes after administration. Per reporter, patients sought medical attention, however, it was reported that no patients required hospitalization or treatment for the reported reactions, it was unknown if any laboratory studies were performed. No individual patient demographics or administration dates were able to provide. The reporter expressed that she did not wish to continue using any additional doses from that lot/batch and was planning on contacting her distributor to arrange return of the remaining (22) doses. The outcome of the events was unknown.   The reporter did not provide the relationship between the events (vaccination site erythema, vaccination site swelling and vaccination site urticaria) and measles, mumps, and rubella (wistar ra 27-3) virus vaccine, live (M-M-R II).   This is non-valid report referring to multiple patients with no number of patients provided.  An investigation into the manufacture of lot T006166 was completed and confirmed that all in-process quality checks were satisfactory. The results indicated that the lot was manufactured in accordance with manufacturing site standard operating procedures. The lot was confirmed to have met the requirements for market release. Following medical review of the AE report and the Quality investigation, there were no identified concerns related to quality within the results of the investigation.