Blurred vision; Extreme vertigo; virus on vestibular nerve; Extremely dizzy all day; Could not open her eyes for 4 days; Felt like she was wearing a tight sweat band; Throwing up; Pain in left ear; 2 weeks to regain balance; Neck pain, lot of bad neck pain; arm developed large red spot warm to touch and hard; Itchy; felt like she was wearing a tight sweat band; Chills; This is a spontaneous and simultaneously regulatory report  case was received via an unknown source (no reference has been entered for a health authority or license partner) on 26-May-2021 and was forwarded to Moderna on 26-May-2021.    This spontaneous case was reported by a consumer (subsequently medically confirmed) and describes the occurrence of VERTIGO (Extreme vertigo), VISION BLURRED (Blurred vision), DIZZINESS (Extremely dizzy all day), ASTHENOPIA (Could not open her eyes for 4 days), FEELING HOT (Felt like she was wearing a tight sweat band), VOMITING (Throwing up), EAR PAIN (Pain in left ear), BALANCE DISORDER (2 weeks to regain balance) and NECK PAIN (Neck pain, lot of bad neck pain) in a 46-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 037A21B and 029A21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     No Medical History information was reported.   On 09-Mar-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 12-Apr-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On 12-Apr-2021, the patient experienced NECK PAIN (Neck pain, lot of bad neck pain) (seriousness criterion hospitalization), RASH MACULAR (arm developed large red spot warm to touch and hard), PRURITUS (Itchy), FEELING ABNORMAL (felt like she was wearing a tight sweat band) and CHILLS (Chills). On 03-May-2021, the patient experienced VERTIGO (Extreme vertigo) (seriousness criterion hospitalization), VISION BLURRED (Blurred vision) (seriousness criterion hospitalization), DIZZINESS (Extremely dizzy all day) (seriousness criterion hospitalization), ASTHENOPIA (Could not open her eyes for 4 days) (seriousness criterion hospitalization), FEELING HOT (Felt like she was wearing a tight sweat band) (seriousness criterion hospitalization), VOMITING (Throwing up) (seriousness criterion hospitalization), EAR PAIN (Pain in left ear) (seriousness criterion hospitalization) and BALANCE DISORDER (2 weeks to regain balance) (seriousness criterion hospitalization). On an unknown date, the patient experienced VESTIBULAR NEURONITIS (virus on vestibular nerve ). The patient was hospitalized for 1 day due to VERTIGO, then for 5 days due to ASTHENOPIA, BALANCE DISORDER, DIZZINESS, EAR PAIN, FEELING HOT, NECK PAIN and VOMITING. The patient was treated with NACL at an unspecified dose and frequency; ZINC at an unspecified dose and frequency; MECLIZINE [MECLOZINE] at an unspecified dose and frequency; PREDNISONE at an unspecified dose and frequency; DIAZEPAM at an unspecified dose and frequency and ONDANSETRON (ZOFRAN [ONDANSETRON]) at an unspecified dose and frequency. At the time of the report, VERTIGO (Extreme vertigo), VISION BLURRED (Blurred vision), DIZZINESS (Extremely dizzy all day), ASTHENOPIA (Could not open her eyes for 4 days), FEELING HOT (Felt like she was wearing a tight sweat band), VOMITING (Throwing up), EAR PAIN (Pain in left ear), BALANCE DISORDER (2 weeks to regain balance), NECK PAIN (Neck pain, lot of bad neck pain), RASH MACULAR (arm developed large red spot warm to touch and hard), PRURITUS (Itchy), FEELING ABNORMAL (felt like she was wearing a tight sweat band), CHILLS (Chills) and VESTIBULAR NEURONITIS (virus on vestibular nerve ) outcome was unknown.            After 3 weeks of receiving the second dose the patient experienced extremely dizzy all day and throwing up. She went to ER and was kept in ICU for 1 day for extreme vertigo. The patient experienced blurred vision which took 2 weeks to clear and 2 weeks to regain balance. The doctors are treating her as if she had a virus on vestibular nerve. Relevant concomitant medications were not reported. Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.  Nevertheless, an alternative probable diagnosis was provided (confounder) during hospitalization that could explain some of the events (LLT: vestibular neuritis).   Action taken with mRNA-1273 in response to the event was not applicable.; Sender's Comments: Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.  Nevertheless, an alternative probable diagnosis was provided (confounder) during hospitalization that could explain some of the events (LLT: vestibular neuritis).