Rheumatoid arthritis flare up; Cellulitis; Leg infection; COVID-19; This spontaneous case was reported by a consumer and describes the occurrence of RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up) and CELLULITIS (Cellulitis) in a 60-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.    Co-suspect product included non-company product ADALIMUMAB (HUMIRA) for Rheumatoid arthritis.    Concurrent medical conditions included Rheumatoid arthritis (Moderate to severe).   On an unknown date, the patient received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form On an unknown date, received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form, second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form and ADALIMUMAB (HUMIRA) (Subcutaneous) at an unspecified dose. and ADALIMUMAB (HUMIRA) (Subcutaneous) dosage was changed to Citrate free. In January 2022, the patient experienced COVID-19 (COVID-19). On an unknown date, the patient experienced RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up) (seriousness criterion medically significant), CELLULITIS (Cellulitis) (seriousness criterion medically significant) and LOCALISED INFECTION (Leg infection). In 2022, COVID-19 (COVID-19) had resolved. At the time of the report, RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up), CELLULITIS (Cellulitis) and LOCALISED INFECTION (Leg infection) was resolving.            Concomitant product use was not provided by the reporter.  It was unknown if patient was enrolled in a COVID-19 Vaccine Trial.  The patient received dose 3 as booster dose.  The reporter's causality of Humira for the events of infection in leg and cellulitis with Humira(Adalimumab) was reported as no reasonable possibility and for lack of drug effect was reported as probable and for COVID-19 and Rheumatoid arthritis flare up was not provided.  The reporter's causality for the event COVID-19 with Moderna COVID-19 vaccine was reported as possible.  Treatment information was not provided. Company comment: This spontaneous case concerns a male 60-years-old patient, with  medical history of Rheumatoid arthritis under treatment with ADALIMUMAB who experienced the unexpected seriousness criterion medically significant events of Rheumatoid arthritis (AESI) and Cellulitis, the unexpected events of Covid-19 (AESI) and Leg infection in the context of 3rd. dose of mRNA-1273 vaccine.  The medical history of Rheumatoid arthritis is a contributor of the same event. The benefit-risk relationship of mRNA-1273 is not affected by this report. Events seriousness was assessed based on medical judgement.; Sender's Comments: This spontaneous case concerns a male 60-years-old patient, with  medical history of Rheumatoid arthritis under treatment with ADALIMUMAB who experienced the unexpected seriousness criterion medically significant events of Rheumatoid arthritis (AESI) and Cellulitis, the unexpected events of Covid-19 (AESI) and Leg infection in the context of 3rd. dose of mRNA-1273 vaccine.  The medical history of Rheumatoid arthritis is a contributor of the same event. The benefit-risk relationship of mRNA-1273 is not affected by this report. Events seriousness was assessed based on medical judgement.