diarrhea; unable to eat; nausea; internal tremors; fatigue; headache; severe joint pain/muscle pain progressing from shoulders; muscle pain progressing down arms and legs; Autoimmune autonomic ganglionophathy worsening after second Covid-19 vaccine; Extremely ILL; Fever; chills; severe/progressive muscle pain; This spontaneous case was reported by a nurse and describes the occurrence of AUTOIMMUNE DISORDER (Immune response/Autoimmune autonomic ganglionophathy worsening after second Covid-19 vaccine) in a 68-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 042L20A and 037K20A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concurrent medical conditions included Celiac disease, Allergy to antibiotic (Tetracycline), Autoimmune disorder (Autoimmune autonomic ganglionopathy) since 05-Jan-2005 and Hypothyroidism. Concomitant products included LEVOTHYROXINE SODIUM (TIROSINT) from 06-Jan-2006 to an unknown date for Hypothyroidism.   On 22-Jan-2021 at 3:00 PM, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 19-Feb-2021 at 3:00 PM, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On 19-Feb-2021, the patient experienced ILLNESS (Extremely ILL), PYREXIA (Fever), CHILLS (chills) and MYALGIA (severe/progressive muscle pain). On 19-Feb-2021 at 8:00 PM, the patient experienced CONDITION AGGRAVATED (Autoimmune autonomic ganglionophathy worsening after second Covid-19 vaccine). On 20-Feb-2021, PAIN IN EXTREMITY (muscle pain progressing down arms and legs) and ARTHRALGIA (severe joint pain/muscle pain progressing from shoulders). On 21-Feb-2021, the patient experienced FATIGUE (fatigue)., NAUSEA (nausea), DIARRHOEA (duarrhoea), UNABLE TO EAT (eating disorder),  21-Feb-2021, the patient experienced HEADACHE (headache). On 22-Feb-2021, the patient experienced TREMOR (internal tremors). At the time of the report, CONDITION AGGRAVATED (Autoimmune autonomic ganglionophathy worsening after second Covid-19 vaccine) had not resolved and ILLNESS (Extremely ILL), TREMOR (internal tremors), PAIN IN EXTREMITY (muscle pain progressing down arms and legs), PYREXIA (Fever), CHILLS (chills), MYALGIA (severe/progressive muscle pain), ARTHRALGIA (severe joint pain/muscle pain progressing from shoulders), FATIGUE (fatigue), NAUSEA (nausea), DIARRHOEA (duarrhoea), UNABLE TO EAT (eating disorder), and HEADACHE (headache) outcome was unknown.        For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter considered CONDITION AGGRAVATED (Autoimmune autonomic ganglionophathy worsening after second Covid-19 vaccine) to be probably related. No further causality assessments were provided for ILLNESS (Extremely ILL), TREMOR (internal tremors),  PAIN IN EXTREMITY (muscle pain progressing down arms and legs), PYREXIA (Fever), CHILLS (chills), MYALGIA (severe/progressive muscle pain), ARTHRALGIA (severe joint pain/muscle pain progressing from shoulders), FATIGUE (fatigue), NAUSEA (nausea), DIARRHOEA (duarrhoea), UNABLE TO EAT (eating disorder), and HEADACHE (headache).    On the day of the second vaccine, the patient experienced fever, chills, and progressive muscle pain.  In the early morning hours on day two (20 Feb 2021), she had severe muscle pain progressing from shoulders to kidney area, down arms and legs, nausea-was unable to eat, so she was unable to get out of bed on this day.  On day three (21 Feb 2021), the patient experienced muscle pain, fatigue, severe headache, diarrhea, and she continued in bed.  On day four (22 Feb 2021), she was very fatigued, was able to eat normally, and continued with internal tremors.  On 23 Apr 2021, the patient visited her neurologist who suspected lingering effects of the vaccine.  The patient felt the immune response was most likely caused by mRNA-1273 and that there were no other potential causes.   Most recent FOLLOW-UP information incorporated above includes: On 27-Apr-2021: The patient (a nurse) completed the vaccine adverse event reporting form.  Multiple fields updated.; Sender's Comments: Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.