large welt approximately 2x3 inches; Neck, arm and face were swollen; Too painful and hot; Headache; thought maybe it could have been a sub Q dose; pretty severe lymphatic response; Incredibly red at the injection; Incredibly painful at the injection; Incredibly swollen at the injection; weird taste in mouth; sore throat, like a weird sore throat; A spontaneous report  was received from a nurse regarding a female patient who received Moderna's Covid-19 vaccine (mRNA-1273) and experienced incorrect route of product administration, urticaria, swelling, taste disorder, lymphadenopathy, injection site erythema, injection site pain, injection site swelling, oropharyngeal pain, headache, and injection site warmth.   The patient's medical history was not provided. Concomitant product use was not provided by the reporter.   The patient received their first of two planned doses of mRNA-1273 (Lot number 039KZ0A) on 31 Dec 2020 in the right arm for prophylaxis of COVID-19 infection and experienced incorrect route of product administration when it might have been given subcutaneously.  On 31 Dec 2020, after about an hour or two after receiving the vaccine, she experienced a pretty severe lymphatic response. Patient stated after she received the vaccine, it left a weird taste in her mouth and got a sore throat, like a weird sore throat.  On 01 Jan 2021, her arm was incredibly red, painful and swollen at the injection site. A large welt approximately 2x3 inches developed. It was significantly raised, and she could not touch it because it was too painful and hot. She also developed a headache. On 02 Jan 2021, the site grew to 4.5x4 inches and was still hot and raised. The patient stated she went to the emergency department because she was concerned that she might have cellulitis. She was told to monitor it.   On 05 Jan 2021, the welt was the size of a quarter, and the headache resolved.  On 08 Jan 2021, the welt was the size of an eraser. She stated she felt better.  Treatment for the event included acetaminophen and ibuprofen.  Action taken with mRNA-1273 in response to the events was not reported.   The events, lymphadenopathy, injection site erythema, injection site pain, injection site swelling, injection site warmth, taste disorder, oropharyngeal pain, urticaria, and swelling, were considered unknown. The event, incorrect route of product administration was resolved on 31 Dec 2020. The event, headache, was considered resolved on 05 Jan 2021.  The reporter did not provide an assessment of the event, a pretty severe lymphatic response, arm is incredibly red, painful and swollen at the injection, left a weird taste in my mouth, sore throat, large welt approximately 2x3 inches, raised, could not touch too painful and hot, neck, arm and face were swollen and a headache.; Reporter's Comments: This case concerns a female patient, who experienced non-serious unexpected events of urticaria, swelling, taste disorder, oropharyngeal pain, and non-serious expected events of injection site warmth, lymphadenopathy, injection site erythema, injection site pain, injection site swelling and headache. This also refers to a case of incorrect route of product administration for mRNA-1273 (lot # 039KZ0A). However, there were no reported AEs associated with this case of incorrect route of product administration. The event of taste disorder, oropharyngeal pain, lymphadenopathy, injection site erythema, injection site pain, injection site swelling occurred after 1 day after mRNA-1273 (lot # 039KZ0A) administration. The event of urticaria, swelling, injection site warmth, and headache occurred after 2 days of mRNA-1273 (lot # 039KZ0A) administration. The treatment included Tylenol and Motrin. Very limited information regarding this event has been provided at this time.  Based on temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.