COVID-19; This spontaneous case was reported by a physician and describes the occurrence of COVID-19 (COVID-19) in a  patient of an unknown age and gender who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination.    Co-suspect product included non-company product TOZINAMERAN (PFIZER BIONTECH COVID-19 VACCINE) for an unknown indication.    The patient had no known allergies.  Concurrent medical conditions included Hypogonadism, Headache, GERD and Leukopenia (Mild leukopenia). Concomitant products included MORPHINE from 07-Jan-2022 to an unknown date, MIRTAZAPINE from 15-Jun-2021 to an unknown date, TESTOSTERONE from 17-Sep-2021 to an unknown date and PANTOPRAZOLE from 15-Sep-2021 to an unknown date for an unknown indication.   On 02-Feb-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 02-Mar-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 27-Oct-2021, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 16-Apr-2022, the patient received fourth dose of TOZINAMERAN (PFIZER BIONTECH COVID-19 VACCINE) (unknown route) Dose 4. On 11-May-2022, the patient experienced COVID-19 (COVID-19). The patient was treated with NIRMATRELVIR, RITONAVIR (PAXLOVID) (oral) from 12-May-2022 to 18-May-2022 for COVID-19 treatment, at an unspecified dose and frequency. At the time of the report, COVID-19 (COVID-19) had not resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 11-May-2022, SARS-CoV-2 test: positive (Positive) Positive /home  antigen test. On 19-May-2022, SARS-CoV-2 test: negative (Negative) Negative/ tested negative by home test. On 30-May-2022, SARS-CoV-2 test: positive (Positive) Tested Positive.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   The patient had reported Paxlovid rebound. Symptom started on 10-May-2022and patient tested positive on 11-May-2022 with a positive home antigen test. Paxlovid started on 12-May-2022, symptoms improved. On 19-May-2022 tested negative by home test. Patient had sore throat on 28-May-2022, nasal congestion and fatigue. Patient tested positive on 30-May-2022 by home test.  Company comment-This spontaneous case concerns a patient of unknown age and gender with no relevant medical history reported, who experienced the unexpected non serious AESI of Covid 19 approximately 196 days after receiving the 3rd dose of mRNA-1273 vaccine in the covid 19 vaccination series. It was reported that covid symptoms started on 10th May2022, with a positive antigen test next day, treated with Paxlovid from 12th May 2022 to 18th May 2022 for 7 days. Patient improved with negative covid test after completion of Paxlovid. After a week symptoms recurred with a positive covid test. Patient has received first and second dose of Moderna at an interval of 28 days. Also recieved fourth dose of vaccination with co suspect TOZINAMERAN (interchange of vaccine products) 25 days prior to the event Covid-19. The current pandemic situation of COVID 19 may remain as confounder. The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report. Event seriousness assessed per medical judgement.; Sender's Comments: This spontaneous case concerns a patient of unknown age and gender with no relevant medical history reported, who experienced the unexpected non serious AESI of Covid 19 approximately 196 days after receiving the 3rd dose of mRNA-1273 vaccine in the covid 19 vaccination series. It was reported that covid symptoms started on 10th May2022, with a positive antigen test next day, treated with Paxlovid from 12th May 2022 to 18th May 2022 for 7 days. Patient improved with negative covid test after completion of Paxlovid. After a week symptoms recurred with a positive covid test. Patient has received first and second dose of Moderna at an interval of 28 days. Also recieved fourth dose of vaccination with co suspect TOZINAMERAN (interchange of vaccine products) 25 days prior to the event Covid-19. The current pandemic situation of COVID 19 may remain as confounder. The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report. Event seriousness assessed per medical judgement.