Caller stated she had the doses, and within 2 and a half to 3 weeks until she had the last shot, her A-fib started flaring up; She has got arthritis problems with it, in her arm/She's having arthritis problems in her arm and hand; Lost strength on part of it; she has no feeling in her right little finger/the next one is a partial feeling; It hurt so bad/Caller states that on a scale of pain level 1 to 10, the pain was 20/You couldn't touch my arm or my hand, it hurt that bad/the pain is there all the time, it comes and goes, but at least is not as strong as it was a couple weeks ago; The vaccine hit hard; A couple weeks ago she couldn't touch her hand, couldn't put it down, it was nonstop/Caller stated it was bad for several days, it was a 10 hours of non-stop pain; Caller stated that this is what is happening to her, a rheumatoid arthritis flare up; This spontaneous case was reported by a consumer and describes the occurrence of ATRIAL FIBRILLATION (Caller stated she had the doses, and within 2 and a half to 3 weeks until she had the last shot, her A-fib started flaring up), ARTHRITIS (She has got arthritis problems with it, in her arm/She's having arthritis problems in her arm and hand), ASTHENIA (Lost strength on part of it), HYPOAESTHESIA (she has no feeling in her right little finger/the next one is a partial feeling), PAIN (It hurt so bad/Caller states that on a scale of pain level 1 to 10, the pain was 20/You couldn't touch my arm or my hand, it hurt that bad/the pain is there all the time, it comes and goes, but at least is not as strong as it was a couple weeks ago), VACCINATION COMPLICATION (The vaccine hit hard), PAIN IN EXTREMITY (A couple weeks ago she couldn't touch her hand, couldn't put it down, it was nonstop/Caller stated it was bad for several days, it was a 10 hours of non-stop pain) and RHEUMATOID ARTHRITIS (Caller stated that this is what is happening to her, a rheumatoid arthritis flare up) in a 71-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 046A21A and 012A21A) for COVID-19 vaccination.     Concurrent medical conditions included Atrial fibrillation and Arthritis.   On 08-Mar-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 10-Apr-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On an unknown date, the patient experienced ATRIAL FIBRILLATION (Caller stated she had the doses, and within 2 and a half to 3 weeks until she had the last shot, her A-fib started flaring up) (seriousness criteria hospitalization and medically significant), ARTHRITIS (She has got arthritis problems with it, in her arm/She's having arthritis problems in her arm and hand) (seriousness criterion hospitalization), ASTHENIA (Lost strength on part of it) (seriousness criterion hospitalization), HYPOAESTHESIA (she has no feeling in her right little finger/the next one is a partial feeling) (seriousness criterion hospitalization), PAIN (It hurt so bad/Caller states that on a scale of pain level 1 to 10, the pain was 20/You couldn't touch my arm or my hand, it hurt that bad/the pain is there all the time, it comes and goes, but at least is not as strong as it was a couple weeks ago) (seriousness criterion hospitalization), VACCINATION COMPLICATION (The vaccine hit hard) (seriousness criterion hospitalization), PAIN IN EXTREMITY (A couple weeks ago she couldn't touch her hand, couldn't put it down, it was nonstop/Caller stated it was bad for several days, it was a 10 hours of non-stop pain) (seriousness criterion hospitalization) and RHEUMATOID ARTHRITIS (Caller stated that this is what is happening to her, a rheumatoid arthritis flare up) (seriousness criteria hospitalization and medically significant). At the time of the report, ATRIAL FIBRILLATION (Caller stated she had the doses, and within 2 and a half to 3 weeks until she had the last shot, her A-fib started flaring up), ARTHRITIS (She has got arthritis problems with it, in her arm/She's having arthritis problems in her arm and hand), ASTHENIA (Lost strength on part of it), HYPOAESTHESIA (she has no feeling in her right little finger/the next one is a partial feeling), VACCINATION COMPLICATION (The vaccine hit hard), PAIN IN EXTREMITY (A couple weeks ago she couldn't touch her hand, couldn't put it down, it was nonstop/Caller stated it was bad for several days, it was a 10 hours of non-stop pain) and RHEUMATOID ARTHRITIS (Caller stated that this is what is happening to her, a rheumatoid arthritis flare up) outcome was unknown and PAIN (It hurt so bad/Caller states that on a scale of pain level 1 to 10, the pain was 20/You couldn't touch my arm or my hand, it hurt that bad/the pain is there all the time, it comes and goes, but at least is not as strong as it was a couple weeks ago) was resolving.        For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   Caller stated she had the doses, and within 2 and a half to 3 weeks until she had the last shot, her A-fib started flaring up. Within 3 weeks she was hospitalized 4 times. It cancelled out her knee surgery, had to postpone it. She also states that she had got arthritis problems with it, in her arm. She had arthritis problems in her arm and hand, her right hand she could barely use it now. She lost strength on part of it because it hurt so bad.   She states she was hospitalized 4 times and spent 2 to 3 weeks there. Was admitted the 4 times, in and out, in and out, and went also to the emergency room.  She had to have a convergent procedure on her heart because of A-Fib. That time she spent 4 days in the hospital, other times she only spent the night, but was going in and out of A-fib all the time.  Caller stated it has not been pleasant, it has been going on for at least, since the middle of October.  Caller states that on a scale of pain level 1 to 10, the pain was 20. She states she is not exaggerating, and anyone couldn't touch her arm or hand, it hurt that bad. She states she did not have pain before. The vaccine hit hard.  Caller states that she had no feeling in her right little finger, and the next one is a partial feeling, the pain is there all the time, it comes and goes, but at least is not as strong as it was a couple weeks ago. A couple weeks ago she couldn't touch her hand, couldn't put it down, it was nonstop, it lasted for over 10 hours straight, at least after that if it was off a little bit she could get some sleep. It was bad, that was really rough, caller stated. Caller stated it was bad for several days, it was a 10 hours of non-stop pain, and that was rough.   Caller stated that she was having rheumatoid arthritis flare up.  No concomitant product use was provided by the reporter.   No treatment medications were reported.  Company comment: This is a spontaneous case concerning a 71 years old, female patient with no clinical history who experienced the unexpected events of ATRIAL FIBRILLATION (AESI), ARTHRITIS, ASTHENIA, HYPOAESTHESIA, PAIN, VACCINATION COMPLICATION, PAIN IN EXTREMITY, REUMATOID ARTHRITIS The events occurred unknown days after the second dose of mRNA-1273 vaccine The rechallenge is not applicable" as the events occurred after the second dose and no details were provided about the first dose The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.; Sender's Comments: This is a spontaneous case concerning a 71 years old, female patient with no clinical history who experienced the unexpected events of ATRIAL FIBRILLATION (AESI), ARTHRITIS, ASTHENIA, HYPOAESTHESIA, PAIN, VACCINATION COMPLICATION, PAIN IN EXTREMITY, REUMATOID ARTHRITIS The events occurred unknown days after the second dose of mRNA-1273 vaccine The rechallenge is not applicable" as the events occurred after the second dose and no details were provided about the first dose The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.