Covid-19; Axillary abscess; This literature-study case was reported in a literature article and describes the occurrence of COVID-19 (Covid-19) and SUBCUTANEOUS ABSCESS (Axillary abscess) in an 88-year-old patient of an unknown gender who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination.        Concurrent medical conditions included Coronary artery disease, Chronic kidney disease, Diabetes mellitus and Obesity.   On an unknown date, the patient received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On an unknown date, received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On an unknown date,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced COVID-19 (Covid-19) (seriousness criterion hospitalization) and SUBCUTANEOUS ABSCESS (Axillary abscess) (seriousness criterion hospitalization). At the time of the report, COVID-19 (Covid-19) was resolving and SUBCUTANEOUS ABSCESS (Axillary abscess) outcome was unknown. Possible    DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Blood immunoglobulin G (0-1.39): 2.20 (High) 2.20. On an unknown date, Blood immunoglobulin M (0-0.99): 2.62 (High) 2.62. On an unknown date, SARS-CoV-2 test: negative (Negative) Negative and positive (Positive) Positive with cycle threshold of 44.5.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered COVID-19 (Covid-19) and SUBCUTANEOUS ABSCESS (Axillary abscess) to be possibly related.    During the study period, patient was hospitalized with COVID-19 after fully vaccinated.  Patient result interpretation showed Resolving/Resolved infection. Status of hospital discharge was in living condition.  Concomitant product and treatment medication use was not provided by the reporter.  This Literature-Study case concerns an 88 year-old patient, gender unknown, with a history of Coronary artery disease, Chronic kidney disease, obesity and Diabetes mellitus, who experienced the serious (due to hospitalization) unexpected AESI event of COVID19 and the serious (due to hospitalization) unexpected event of Subcutaneous abscess. The event COVID19 occurred approximately 50 days after the second dose of Moderna COVID-19 vaccine and the event Subcutaneous abscess on an unknown date. The latency between doses was not disclosed, so although the report states a vaccine breakthrough infection, Lack of efficacy was not captured. The rechallenge was not applicable. The medical history, of Coronary artery disease, Chronic kidney disease, obesity and Diabetes mellitus, remains a confounder for the events and hospitalization. The benefit-risk relationship of Moderna COVID-19 vaccine is not affected by this report.   This case was linked to MOD-2021-362896, MOD-2021-362915 (Patient Link).; Sender's Comments: This Literature-Study case concerns an 88 year-old patient, gender unknown, with a history of Coronary artery disease, Chronic kidney disease, obesity and Diabetes mellitus, who experienced the serious (due to hospitalization) unexpected AESI event of COVID19 and the serious (due to hospitalization) unexpected event of Subcutaneous abscess. The event COVID19 occurred approximately 50 days after the second dose of Moderna COVID-19 vaccine and the event Subcutaneous abscess on an unknown date. The latency between doses was not disclosed, so although the report states a vaccine breakthrough infection, Lack of efficacy was not captured. The rechallenge was not applicable. The medical history, of Coronary artery disease, Chronic kidney disease, obesity and Diabetes mellitus, remains a confounder for the events and hospitalization. The benefit-risk relationship of Moderna COVID-19 vaccine is not affected by this report.