This spontaneous case was reported by a consumer and describes the occurrence of COVID-19 (COVID-19/Paxlovid rebound, I tested negative on Friday 5/27 and was feeling better. then Monday night 5/30 I began having runny nose and this morning 5/31 tested positive again) and INTERCHANGE OF VACCINE PRODUCTS (Interchange of vaccine products) in a 27-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 023C21A) for COVID-19 vaccination. Previously administered products included for Product used for unknown indication: JANSSEN COVID-19 VACCINE (Dose Number: 1 Batch/Lot No: 1805029) on 24-Mar-2021. Past adverse reactions to the above products included No adverse event with JANSSEN COVID-19 VACCINE. Concurrent medical conditions included Asthma, Allergy to antibiotic (amoxycillin), Fish allergy (fish) and Shellfish allergy (shellfish). Concomitant products included VENLAFAXINE from 26-Jul-2021 to an unknown date and BECLOMETASONE DIPROPIONATE (QVAR) from 01-Aug-2021 to an unknown date for an unknown indication. On 14-Dec-2021, the patient received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 14-Dec-2021, the patient experienced INTERCHANGE OF VACCINE PRODUCTS (Interchange of vaccine products). In May 2022, the patient experienced COVID-19 (COVID-19/Paxlovid rebound, I tested negative on Friday 5/27 and was feeling better. then Monday night 5/30 I began having runny nose and this morning 5/31 tested positive again). The patient was treated with NIRMATRELVIR, RITONAVIR (PAXLOVID) from 21-May-2022 to 26-May-2022 for COVID-19 treatment, at an unspecified dose and frequency. At the time of the report, COVID-19 (COVID-19/Paxlovid rebound, I tested negative on Friday 5/27 and was feeling better. then Monday night 5/30 I began having runny nose and this morning 5/31 tested positive again) 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 27-May-2022, SARS-CoV-2 test: negative (Negative) Negative. On 31-May-2022, SARS-CoV-2 test: positive (Positive) Positive. The patient previously received a COVID-19 Vaccine. It was reported that he patient was taking other medications/products within 2 weeks of starting COVID-19 treatment. She began having runny nose and this morning 5/31 tested positive again. Device Date : 31May2022. Company Comment: This spontaneous case concerns a 27-year-old, female patient, with no relevant medical history reported, who experienced an unexpected, non-serious AESI COVID-19 in association with a dose of mRNA-1273 vaccine as her 2nd COVID-19 vaccination. Exact onset latency of the event COVID-19 cannot be determined with an unknown event onset date. Her 1st COVID-19 vaccination with a dose of Janssen vaccine was given approximately 9 months before she received a dose of mRNA-1273 vaccine. Paxlovid treatment for COVID-19 was started 5 months after her vaccination with mRNA-1273 vaccine. Patient felt better and tested negative with COVID-19 the next day after completing Paxlovid treatment. She began having runny nose 3 days later. She tested positive again 4 days after Paxlovid treatment. Event outcome of COVID-19 was reported as not resolved. Further details on the medical history, clinical course, diagnostics, and treatments were not reported. The benefit-risk relationship of mRNA-1273 is not affected by this report. Event's seriousness assessed based on medical judgement and the available information. Sender's Comments: This spontaneous case concerns a 27-year-old, female patient, with no relevant medical history reported, who experienced an unexpected, non-serious AESI COVID-19 in association with a dose of mRNA-1273 vaccine as her 2nd COVID-19 vaccination. Exact onset latency of the event COVID-19 cannot be determined with an unknown event onset date. Her 1st COVID-19 vaccination with a dose of Janssen vaccine was given approximately 9 months before she received a dose of mRNA-1273 vaccine. Paxlovid treatment for COVID-19 was started 5 months after her vaccination with mRNA-1273 vaccine. Patient felt better and tested negative with COVID-19 the next day after completing Paxlovid treatment. She began having runny nose 3 days later. She tested positive again 4 days after Paxlovid treatment. Event outcome of COVID-19 was reported as not resolved. Further details on the medical history, clinical course, diagnostics, and treatments were not reported. The benefit-risk relationship of mRNA-1273 is not affected by this report. Event's seriousness assessed based on medical judgement and the available information.