Started having cognitive problems; severe chills; sweating; headaches; Fever; Felt extremely weak; This spontaneous case was reported by a patient family member or friend (subsequently medically confirmed) and describes the occurrence of CHILLS (severe chills), HYPERHIDROSIS (sweating), HEADACHE (headaches), PYREXIA (Fever) and COGNITIVE DISORDER (Started having cognitive problems) in an 83-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 013L20A and 010M20A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concomitant products included HYDRALAZINE, TOFACITINIB CITRATE (XELJANZ), SIMVASTATIN, LEVOTHYROXINE SODIUM (SYNTHROID), METOPROLOL and CALCIUM for an unknown indication.   On 19-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 17-Feb-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 2 dosage form. On 18-Feb-2021,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced ASTHENIA (Felt extremely weak). On 01-Apr-2021, the patient experienced CHILLS (severe chills) (seriousness criterion hospitalization), HYPERHIDROSIS (sweating) (seriousness criterion hospitalization), HEADACHE (headaches) (seriousness criterion hospitalization) and PYREXIA (Fever) (seriousness criterion hospitalization). On 08-Apr-2021, the patient experienced COGNITIVE DISORDER (Started having cognitive problems) (seriousness criterion hospitalization). At the time of the report, CHILLS (severe chills), HYPERHIDROSIS (sweating), HEADACHE (headaches), PYREXIA (Fever), COGNITIVE DISORDER (Started having cognitive problems) and ASTHENIA (Felt extremely weak) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In 2021, SARS-CoV-2 test: negative (Negative) negative.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter did not provide any causality assessments.   It was reported that the patient became very ill starting around 01-Apr-2021 and had two emergency room visits and was hospitalized. The tests from her hospital visit came back without a specific diagnosis and the doctors did not feel her hospital admittance or symptoms were due to having received the Moderna COVID-19 Vaccine. The reporter felt a possibility, although not officially diagnosed and strictly in his opinion that the patient might have sudden onset of Alzheimer's. The patient was treated with antibiotic starting on 03-Apr-2021 and tylenol. Action taken with mRNA-1273 in response to the events was not applicable.  No reported past medical history The patient did not have COVID-19  Based on the current available information and temporal association between the use of the product and the start date of the event of asthenia, a causal relationship cannot be excluded, however based on reporter causality and lack of temporal association the events of chills, fever, headache and hyperhidrosis were assessed as unlikely related; Sender's Comments: Based on the current available information and temporal association between the use of the product and the start date of the event of asthenia, a causal relationship cannot be excluded, however based on reporter causality and lack of temporal association the events of chills, fever, headache and hyperhidrosis were assessed as unlikely related