Headache; body ache; chills; pyrexia; Covid-19; the interval between the first and the second dose was 43 days; This spontaneous case was reported by a patient family member or friend and describes the occurrence of HEADACHE (Headache), MYALGIA (body ache), CHILLS (chills), PYREXIA (pyrexia) and COVID-19 (Covid-19) in a 21-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 051C21A and 024CZ1A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concurrent medical conditions included Congenital hypothyroidism (By birth). Concomitant products included LEVOTHYROXINE SODIUM (SYNTHROID) from 20-Dec-2000 to an unknown date for an unknown indication.   On 10-May-2021 at 4:00 PM, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 22-Jun-2021 at 11:00 AM, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 22-Jun-2021,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced INAPPROPRIATE SCHEDULE OF PRODUCT ADMINISTRATION (the interval between the first and the second dose was 43 days). On 07-Sep-2021, the patient experienced COVID-19 (Covid-19). On an unknown date, the patient experienced HEADACHE (Headache), MYALGIA (body ache), CHILLS (chills) and PYREXIA (pyrexia). On 22-Jun-2021, INAPPROPRIATE SCHEDULE OF PRODUCT ADMINISTRATION (the interval between the first and the second dose was 43 days) had resolved. At the time of the report, HEADACHE (Headache), MYALGIA (body ache), CHILLS (chills), PYREXIA (pyrexia) and COVID-19 (Covid-19) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 07-Sep-2021, SARS-CoV-2 test positive: positive (Positive) Positive.     mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown) dosing remained unchanged.   For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   The patient received the third dose on 05-Jan-2022 and the events Headache, Myalgia, Chills and Pyrexia reoccurred.  Company comment: This is a spontaneous case concerning a 21-year-old female patient with medical history of congenital hypothyroidism, who experienced the unexpected non-serious AESI of COVID-19, as well as non-serious expected events of Headache, Myalgia, Chills and Pyrexia. The event of COVID-19 occurred approximately two and a half months after the second dose of mRNA-1273 vaccine, while onset dates of other events were not reported. After administration of the third dose, the events Headache, Myalgia, Chills and Pyrexia reoccurred. Limited information regarding the event of COVID-19 was provided. It was reported that the interval between the first and the second dose was 43 days, which suggests Inappropriate schedule of vaccine administered. Therefore, lack of efficacy cannot be determined. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.   This case was linked to MOD-2022-443899 (Patient Link).; Sender's Comments: This is a spontaneous case concerning a 21-year-old female patient with medical history of congenital hypothyroidism, who experienced the unexpected non-serious AESI of COVID-19, as well as non-serious expected events of Headache, Myalgia, Chills and Pyrexia. The event of COVID-19 occurred approximately two and a half months after the second dose of mRNA-1273 vaccine, while onset dates of other events were not reported. After administration of the third dose, the events Headache, Myalgia, Chills and Pyrexia reoccurred. Limited information regarding the event of COVID-19 was provided. It was reported that the interval between the first and the second dose was 43 days, which suggests Inappropriate schedule of vaccine administered. Therefore, lack of efficacy cannot be determined. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.