Relapse of COVID symptoms and positive antigen test; Interchange of vaccine products; This spontaneous case was reported by a patient and describes the occurrence of COVID-19 (Relapse of COVID symptoms and positive antigen test) and INTERCHANGE OF VACCINE PRODUCTS (Interchange of vaccine products) in a 54-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. Co-suspect product included non-company product COVID-19 VACCINE NRVV AD26 (JNJ 78436735) (JANSSEN COVID-19 VACCINE) for an unknown indication. Concurrent medical conditions included Pre-diabetic (Pre-diabetic) and Fruit allergy (Mango). Concomitant products included LEVOTHYROXINE SODIUM (SYNTHYROID) for an unknown indication. On 16-Apr-2021 at 12:00 PM, the patient received first dose of COVID-19 VACCINE NRVV AD26 (JNJ 78436735) (JANSSEN COVID-19 VACCINE) (unknown route) 1 dosage form. On 15-Oct-2021 at 4:00 PM, the patient received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 15-Apr-2022 at 12:00 PM, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 15-Oct-2021,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced INTERCHANGE OF VACCINE PRODUCTS (Interchange of vaccine products). On 25-May-2022 at 7:00 AM, the patient experienced COVID-19 (Relapse of COVID symptoms and positive antigen test). At the time of the report, COVID-19 (Relapse of COVID symptoms and positive antigen test) had not resolved and INTERCHANGE OF VACCINE PRODUCTS (Interchange of vaccine products) outcome was unknown. DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 25-May-2022, SARS-CoV-2 test: positive (Positive) Positive. The patient received unspecified medications/products within 2 weeks of starting COVID-19 treatment. The patient received unspecified Pfizer medication from 16-May-2022 to 20-May-2022 for COVID-19 treatment. The device date was 26-May-2022. Company comment: This is a spontaneous case concerning a 55-year-old female patient with no relevant medical history reported, previously received Janssen COVID-19 Vaccine, who experienced the non-serious, unexpected  event of COVID-19, which occurred approximately 40 days after the 3rd dose of mRNA-1273. Interchange of vaccine products was considered an additional event. It was reported that the patient experienced COVID-19 five days after completing a 4-days treatment with a Pfizer product. Relapse of COVID symptoms and positive antigen test was also reported. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.; Sender's Comments: This is a spontaneous case concerning a 55-year-old female patient with no relevant medical history reported, previously received Janssen COVID-19 Vaccine, who experienced the non-serious, unexpected  event of COVID-19, which occurred approximately 40 days after the 3rd dose of mRNA-1273. Interchange of vaccine products was considered an additional event. It was reported that the patient experienced COVID-19 five days after completing a 4-days treatment with a Pfizer product. Relapse of COVID symptoms and positive antigen test was also reported. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.