Paxlovid Rebound: COVID sx's (aches, cough, & fatigue)/COVID Sx's (body aches) evening 10/23; further sx's (nasal congestion, fatigue); This spontaneous case was reported by a patient and describes the occurrence of COVID-19 (Paxlovid Rebound: COVID sx's (aches, cough, & fatigue)/COVID Sx's (body aches) evening 10/23; further sx's (nasal congestion, fatigue)) in a 60-year-old female patient who received mRNA-1273.815 (SPIKEVAX 2023-2024 PFS) (batch no. 203E23A) for COVID-19 prophylaxis.     Previously administered products included for COVID-19 prophylaxis: Spikevax (Dose 1, Dose (number): 0.5 milliliter, Batch/lot number:027L20A, Route of Administration: Intramuscular.) on 11-Jan-2021, Spikevax (Dose 2, Dose (number): 0.5 milliliter, Batch/lot number:016M20A, Route of Administration: Intramuscular.) on 08-Feb-2021, Spikevax (Dose 3, Dose (number): 0.5 milliliter, Batch/lot number:053E21A, Route of Administration: Intramuscular.) on 23-Aug-2021, Spikevax (Dose 4, Dose (number): 0.5 milliliter, Batch/lot number:025L21B, Route of Administration: Intramuscular.) on 23-Feb-2022, MODERNA COVID-19 VACCINE, BIVALENT (ORIGINAL AND OMICRON BA.4/BA.5) (Dose 5, Dose (number): 0.5 milliliter, Batch/lot number:AS7145B, Route of Administration: Intramuscular.) on 15-Sep-2022, MODERNA COVID-19 VACCINE, BIVALENT (ORIGINAL AND OMICRON BA.4/BA.5) (Dose 6, Dose (number): 0.5 milliliter, Batch/lot number:069H22A and Route of Administration: Intramuscular.) on 27-Apr-2023. Past adverse reactions to the above products included No adverse reaction with MODERNA COVID-19 VACCINE, BIVALENT (ORIGINAL AND OMICRON BA.4/BA.5), MODERNA COVID-19 VACCINE, BIVALENT (ORIGINAL AND OMICRON BA.4/BA.5), Spikevax, Spikevax, Spikevax and Spikevax.    On 02-Oct-2023, the patient received seventh dose of mRNA-1273.815 (SPIKEVAX 2023-2024 PFS) (Intramuscular use) .5 milliliter. On 15-Oct-2023,  after starting mRNA-1273.815 (SPIKEVAX 2023-2024 PFS), the patient experienced COVID-19 (Paxlovid Rebound: COVID sx's (aches, cough, & fatigue)/COVID Sx's (body aches) evening 10/23; further sx's (nasal congestion, fatigue)). The patient was treated with NIRMATRELVIR, RITONAVIR (PAXLOVID) from 16-Oct-2023 to 20-Oct-2023 at an unspecified dose and frequency. At the time of the report, COVID-19 (Paxlovid Rebound: COVID sx's (aches, cough, & fatigue)/COVID Sx's (body aches) evening 10/23; further sx's (nasal congestion, fatigue)) had not resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 16-Oct-2023, SARS-CoV-2 test: Positive. On 24-Oct-2023, SARS-CoV-2 test: Positive.     For mRNA-1273.815 (SPIKEVAX 2023-2024 PFS) (Intramuscular use), the reporter did not provide any causality assessments.   Concomitant medications were not reported.  It was reported that patient got Paxlovid Rebound: COVID symptoms (sx's) (aches, cough, & fatigue) on 15-Oct-2023, Tested COVID positive on 16-Oct-2023, Paxlovid treatment given from 10/16-10/20, COVID on 20-Oct-2023, COVID Sx's (body aches) evening on 23-Oct-2023; further sx's (nasal congestion, fatigue) on 24-Oct-2023, Tested COVID positive 24-Oct-2023. It is unknown if the patient experienced any additional symptoms/events.