Right leg also started swelling/her leg is almost 1.5-2 inches bigger on the right when compared to the left.; Reaction like her typical reactions to the flu vaccine.; Very sick; Fever; Chills; Joint aches; Muscle aches; Headache; With the second dose of the vaccine where her rash got better; This spontaneous case was reported by a nurse and describes the occurrence of PERIPHERAL SWELLING (Right leg also started swelling/her leg is almost 1.5-2 inches bigger on the right when compared to the left.), IMMUNISATION REACTION (Reaction like her typical reactions to the flu vaccine.), ILLNESS (Very sick), PYREXIA (Fever) and CHILLS (Chills) in a female patient of an unknown age who received mRNA-1273 (Spikevax) for COVID-19 prophylaxis. The occurrence of additional non-serious events is detailed below.     The patient's past medical history included Lymphadenectomy (lymph node removed out of right leg prior to chemotherapy had minor swelling since the surgery) and Chemotherapy. Previously administered products included for Product used for unknown indication: Flu vaccine (adverse reaction not specified). Past adverse reactions to the above products included Adverse reaction with Flu vaccine. Concurrent medical conditions included Autoimmune disorder (breaks out in an alligator skin-like blisters on legs that itch (presumed to be Wells disease).) and Cancer. Concomitant products included RITUXIMAB from an unknown date to 26-Jan-2022 for Cancer, TRIAMCINOLONE and LORATADINE, PSEUDOEPHEDRINE SULFATE (CLARITIN EXTRA) for an unknown indication.   On 27-Jan-2022, the patient received first dose of mRNA-1273 (Spikevax) (unknown route) 1 dosage form. On 24-Feb-2022, received second dose of mRNA-1273 (Spikevax) (unknown route) dosage was changed to 1 dosage form. In February 2022, the patient experienced PERIPHERAL SWELLING (Right leg also started swelling/her leg is almost 1.5-2 inches bigger on the right when compared to the left.), IMMUNISATION REACTION (Reaction like her typical reactions to the flu vaccine.), ILLNESS (Very sick), PYREXIA (Fever), CHILLS (Chills), ARTHRALGIA (Joint aches), MYALGIA (Muscle aches), HEADACHE (Headache) and THERAPEUTIC RESPONSE UNEXPECTED (With the second dose of the vaccine where her rash got better). At the time of the report, PERIPHERAL SWELLING (Right leg also started swelling/her leg is almost 1.5-2 inches bigger on the right when compared to the left.), IMMUNISATION REACTION (Reaction like her typical reactions to the flu vaccine.), ILLNESS (Very sick), PYREXIA (Fever), CHILLS (Chills), ARTHRALGIA (Joint aches), MYALGIA (Muscle aches), HEADACHE (Headache) and THERAPEUTIC RESPONSE UNEXPECTED (With the second dose of the vaccine where her rash got better) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Ultrasound scan: did not show a clot Did not show a clot.     For mRNA-1273 (Spikevax) (Unknown), the reporter did not provide any causality assessments.   Other concomitant medication included Eulaxa.  Patient last appointment for the treatment for cancer was in January and the next day after last dose was when patient received the dose.  Following the second shot, 13 hours later patient was very sick.  She was in bed, for 5 days with these symptoms. Patient had right leg swelling. She had lymph node removed out of her right leg. This swelling was worse when standing or walking around. She has had a minor amount of swelling since surgery, but her leg was almost 1.5-2 inches bigger on the right when compared to the left.   Patient was presumed to have Wells disease, and had a break out at the time of the first shot. The symptoms went away after receiving the dose. A similar thing happened with the second dose of the vaccine where her rash got better. She had also been taking triamcinolone and an extra Claritin a day for those symptoms.  On 24-Mar-2022, patient received third dose of Moderna vaccine. She was attempting to receive a booster dose of the Moderna COVID-19 vaccine from a pharmacy, but was denied vaccination.  Treatment included Compression socks.   This case was linked to MOD-2022-595633 (Patient Link).