Atrial fibrillation; COVID vaccine triggered something in body that triggered the big Rheumatoid Arthritis flare-up; Pain; Sick; experienced COVID; experienced Norovirus; This spontaneous case was reported by a consumer and describes the occurrence of ATRIAL FIBRILLATION (Atrial fibrillation) and RHEUMATOID ARTHRITIS (COVID vaccine triggered something in body that triggered the big Rheumatoid Arthritis flare-up) in a 49-year-old female 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.    The patient's past medical history included Knee replacement in 2017. Concurrent medical conditions included Rheumatoid arthritis. Concomitant products included METHOTREXATE for an unknown indication.   In 2021, the patient received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. In 2021, received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On an unknown date, the patient started ADALIMUMAB (HUMIRA) (Subcutaneous) 40 milligram. In May 2022, the patient experienced COVID-19 (experienced COVID). In 2022, the patient experienced NOROVIRUS INFECTION (experienced Norovirus). On an unknown date, the patient experienced ATRIAL FIBRILLATION (Atrial fibrillation) (seriousness criterion medically significant), RHEUMATOID ARTHRITIS (COVID vaccine triggered something in body that triggered the big Rheumatoid Arthritis flare-up) (seriousness criterion medically significant), PAIN (Pain) and ILLNESS (Sick). The patient was treated with RIVAROXABAN (XARELTO) at an unspecified dose and frequency. At the time of the report, ATRIAL FIBRILLATION (Atrial fibrillation), RHEUMATOID ARTHRITIS (COVID vaccine triggered something in body that triggered the big Rheumatoid Arthritis flare-up), NOROVIRUS INFECTION (experienced Norovirus), COVID-19 (experienced COVID) and PAIN (Pain) outcome was unknown and ILLNESS (Sick) had resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In May 2022, SARS-CoV-2 test: (Positive) Positive.         Moderna-. It was unknown if patient was enrolled in COVID-19-Vaccine Trial. The patient got first COVID vaccine in 2021 and three months after second vaccine she started having really bad pain so severe. She switched from oral Methotrexate to Methotrexate injections once a week and it works best with HUMIRA. Agency's opinion was that the causality for the event(s) of COVID, COVID vaccine triggered something in body that triggered the big Rheumatoid Arthritis flare-up, Double knee replacement and Pain with Adalimumab Solution for Injection was No Reasonable Possibility. Agency's opinion was that the causality for the event(s) of Atrial fibrillation, Norovirus and Sick with Adalimumab Solution for Injection was Not Assessable  Company Comment: This spontaneous case concerns a 49-year-old female patient, with a relevant history of rheumatoid arthritis and concomitant use of adalimumab and methotrexate, who experienced the unexpected serious (medically significant) AESI Atrial fibrillation and Rheumatoid arthritis flare up, which occurred unknown days after receiving a dose of mRNA-1273 vaccine, along with non-serious events COVID-19 and Pain. The outcome was reported as unknown. It was reported that the patient got the first COVID vaccine dose in 2021 and three months after second dose she started having severe pain. Diagnostic workup or treatment information were not reported. Underlying history of rheumatoid arthritis and concomitant use of adalimumab and methotrexate could be confounder for the event Rheumatoid arthritis flare up, COVID-19 and Pain. The benefit-risk relationship of mRNA-1273 is not affected by this report.; Sender's Comments: This spontaneous case concerns a 49-year-old female patient, with a relevant history of rheumatoid arthritis and concomitant use of adalimumab and methotrexate, who experienced the unexpected serious (medically significant) AESI Atrial fibrillation and Rheumatoid arthritis flare up, which occurred unknown days after receiving a dose of mRNA-1273 vaccine, along with non-serious events COVID-19 and Pain. The outcome was reported as unknown. It was reported that the patient got the first COVID vaccine dose in 2021 and three months after second dose she started having severe pain. Diagnostic workup or treatment information were not reported. Underlying history of rheumatoid arthritis and concomitant use of adalimumab and methotrexate could be confounder for the event Rheumatoid arthritis flare up, COVID-19 and Pain. The benefit-risk relationship of mRNA-1273 is not affected by this report.