Rebound COVID/ I was positive again on rapid antigen test; This spontaneous case was reported by a nurse and describes the occurrence of COVID-19 (Rebound COVID/ I was positive again on rapid antigen test) in a 46-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 033F21A) for COVID-19 vaccination.    Co-suspect product included non-company product NIRMATRELVIR, RITONAVIR (PAXLOVID) for COVID-19 treatment.    Concomitant products included ETHINYLESTRADIOL, ETONOGESTREL (NUVARING) from 01-Sep-2019 to 25-May-2022 for an unknown indication.   On 01-Nov-2021, the patient received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 13-May-2022, the patient started NIRMATRELVIR, RITONAVIR (PAXLOVID) (unknown route) at an unspecified dose. In May 2022, the patient experienced COVID-19 (Rebound COVID/ I was positive again on rapid antigen test). At the time of the report, COVID-19 (Rebound COVID/ I was positive again on rapid antigen test) had not resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 13-May-2022, SARS-CoV-2 test: positive (Positive) Positive. In May 2022, SARS-CoV-2 test: positive (Positive) Positive. On 17-May-2022, SARS-CoV-2 test: negative (Negative) Negative. On 23-May-2022, SARS-CoV-2 test: negative (Negative) Negative.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   Reportedly, the patient was taking other medications/products within 2 weeks of starting COVID-19 treatment. Patient was originally tested positive on 13-May-2022 but symptoms started in the evening of 12-May-2022 and her COVID symptoms started to improve on 15-May-2022. Patient never felt completely 100 percent, but she continued to improve. Patient started testing negative on 17-May-2022 on home rapid antigen. Patient had started to feel unwell again on the evening of 23-May-2022 and woke up on 24-May-2022 with congestion and cough. By the afternoon, she had a low grade fever and worsening congestion/cough/headache. Patient assumed she was getting a secondary sinus infection, but had been reading about rebound COVID, so tested herself and was negative on 23-May-2022 and was positive again on rapid antigen test.  No treatment information was provided.  Device Date was reported as 25-May-2022. Company comment: This spontaneous case concerns a 46-year-old female patient with no reported medical history, who experienced the unexpected, non-serious adverse event of special interest COVID-19 (with a positive SARS-CoV-2 test). The event occurred after administration of third dose of mRNA-1273 approximately 6 months prior, the exact date of onset of the event was not specified. There was no information provided regarding the initial two doses. On May 13, 2022, the patient took a SARS-CoV-2 which revealed a positive result, the test yielded a negative result on May 17 and 23, 2022. It has been reported that the patient never felt completely well but had improving conditions. Patient had started to feel unwell again on the evening of May 23, 2022, and woke the next day with congestion, cough, headache and low-grade fever. Outcome of the events was unknown at the time of this report. The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report.; Sender's Comments: This spontaneous case concerns a 46-year-old female patient with no reported medical history, who experienced the unexpected, non-serious adverse event of special interest COVID-19 (with a positive SARS-CoV-2 test). The event occurred after administration of third dose of mRNA-1273 approximately 6 months prior, the exact date of onset of the event was not specified. There was no information provided regarding the initial two doses. On May 13, 2022, the patient took a SARS-CoV-2 which revealed a positive result, the test yielded a negative result on May 17 and 23, 2022. It has been reported that the patient never felt completely well but had improving conditions. Patient had started to feel unwell again on the evening of May 23, 2022, and woke the next day with congestion, cough, headache and low-grade fever. Outcome of the events was unknown at the time of this report. The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report.