interchange of vaccine products; COVID-19; This spontaneous case was reported by a consumer and describes the occurrence of COVID-19 (COVID-19) and INTERCHANGE OF VACCINE PRODUCTS (interchange of vaccine products) in a 35-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 022J21A) for COVID-19 vaccination.     Previously administered products included for Product used for unknown indication: PFIZER BIONTECH COVID-19 VACCINE (Dose Number: 1 Batch/Lot No: EP6955 Location of injection: Arm Left Vaccine Administration Time: 05:00 PM) on 18-Mar-2021, Pfizer / BioNTech (Dose Number: 2 Batch/Lot No: EW0151 Location of injection: Arm Left Vaccine Administration Time: 05:00 PM) on 09-Apr-2021 and Pfizer / BioNTech (Dose Number: 3 Batch/Lot No: EW0185 Location of injection: Arm Left Vaccine Administration Time: 05:00 PM) on 19-Aug-2021. Past adverse reactions to the above products included No adverse event with PFIZER BIONTECH COVID-19 VACCINE, Pfizer / BioNTech and Pfizer / BioNTech. Concurrent medical conditions included Crohn's disease and Allergy to antibiotic. Concomitant products included DEXLANSOPRAZOLE and INFLIXIMAB (INFLECTRA [INFLIXIMAB]) for an unknown indication.    On 21-Jan-2022, the patient received fourth dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 19-May-2022, the patient experienced COVID-19 (COVID-19). On an unknown date, the patient experienced INTERCHANGE OF VACCINE PRODUCTS (interchange of vaccine products). The patient was treated with NIRMATRELVIR, RITONAVIR (PAXLOVID) on 19-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 and INTERCHANGE OF VACCINE PRODUCTS (interchange of vaccine products) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 19-May-2022, SARS-CoV-2 test: positive (Positive) Positive. On 24-May-2022, SARS-CoV-2 test: negative (Negative) Negative. On 31-May-2022, SARS-CoV-2 test: negative (Negative) Negative. On 02-Jun-2022, Body temperature: 101.0 101.0 fever. On 02-Jun-2022, SARS-CoV-2 test: positive (Positive) Positive.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   On 24-May-2022, patient felt asymptomatic. However as of 31-May-2022 patient  started to feel unwell, and mildly feverish with a cough.  As of that morning, patient  now experienced a proper 101.0 fever, loud cough, big headache and body aches. Patient took the five day course of Paxlovid.  Company comment-This spontaneous case concerns a male patient aged 35 years with no relevant medical history reported, who experienced the unexpected non serious AESI of Covid 19 approximately 3 months 28 days after receiving the 4th dose of mRNA-1273 vaccine in the covid 19 vaccination series. It was reported that the patient was treated for covid infection with Paxlovid from 19th May 2022 for 5 days. Patient recovered with negative covid test. After several days symptoms recurred with a positive covid test. Patient has received initial schedule of vaccinations (dose 1,2 and 3) with TOZINAMERAN (interchange of vaccine products) noted. 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 male patient aged 35 years with no relevant medical history reported, who experienced the unexpected non serious AESI of Covid 19 approximately 3 months 28 days after receiving the 4th dose of mRNA-1273 vaccine in the covid 19 vaccination series. It was reported that the patient was treated for covid infection with Paxlovid from 19th May 2022 for 5 days. Patient recovered with negative covid test. After several days symptoms recurred with a positive covid test. Patient has received initial schedule of vaccinations (dose 1,2 and 3) with TOZINAMERAN (interchange of vaccine products) noted. 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.