covid-19 prior to Paxlovid treatment; interchange of vaccine products; This spontaneous case was reported by a patient and describes the occurrence of COVID-19 (covid-19 prior to Paxlovid treatment) in a 51-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for Prophylactic vaccination. The occurrence of additional non-serious events is detailed below.    Co-suspect product included non-company product COVID-19 VACCINE NRVV AD26 (JNJ 78436735) (JANSSEN COVID-19 VACCINE) for Prophylactic vaccination.    Concurrent medical conditions included Hashimoto's disease (Very low level hashimotos, not taking medications) and Drug allergy (drug not specified).   On 04-Apr-2021, the patient received first dose of COVID-19 VACCINE NRVV AD26 (JNJ 78436735) (JANSSEN COVID-19 VACCINE) (unknown route) 1 dosage form. In November 2021, the patient received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. In November 2021, the patient experienced INTERCHANGE OF VACCINE PRODUCTS (interchange of vaccine products). On an unknown date, the patient experienced COVID-19 (covid-19 prior to Paxlovid treatment) (seriousness criterion medically significant). The patient was treated with NIRMATRELVIR, RITONAVIR (PAXLOVID) from 03-May-2022 to 08-May-2022 for COVID-19, at an unspecified dose and frequency. At the time of the report, COVID-19 (covid-19 prior to Paxlovid treatment) had resolved and INTERCHANGE OF VACCINE PRODUCTS (interchange of vaccine products) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In May 2022, SARS-CoV-2 test: (Positive) positive and (Positive) positive.         The patient was not taking any other medications/products within two weeks of starting COVID-19 (corona virus disease) treatment.  Concomitant product use was not provided by the reporter.  Patient was not pregnant at the time of vaccination.  On 03-May-2022 at 14:00 (Friday night) the patient had night onset of fever, runny nose, sneezing, exhaustion (after contacting virus) (confirmed COVID-19 infection). Fever lasted for one night and all other symptoms lasted for a week. Company comment: This spontaneous case concerns a 51-year-old female patient with no relevant medical history reported, who experienced the unexpected serious (medically significant) AESI event of COVID-19 which occurred unspecified days after receiving the second dose of mRNA-1273 vaccine. Patient was treated with Paxlovid 5 days for Covid-19. 5 days after completing the course of paxlovid patient experienced covid rebound symptoms. It was noted that patient received a dose with JANSSEN COVID-19 VACCINE prior to current vaccination(interchange of vaccine products).The current pandemic situation of COVID-19 may remain as confounder to the event Covid-19.  The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report.; Sender's Comments: This spontaneous case concerns a 51-year-old female patient with no relevant medical history reported, who experienced the unexpected serious (medically significant) AESI event of COVID-19 which occurred unspecified days after receiving the second dose of mRNA-1273 vaccine. Patient was treated with Paxlovid 5 days for Covid-19. After 5 days,completing the course of paxlovid patient experienced covid rebound symptoms. It was noted that patient received a dose with JANSSEN COVID-19 VACCINE prior to current vaccination(interchange of vaccine products).The current pandemic situation of COVID-19 may remain as confounder to the event Covid-19.  The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report.