SUSPECTED CLINICAL VACCINATION FAILURE; SUSPECTED COVID-19 INFECTION; This spontaneous report received from a consumer concerned a 63 year old male. The patient's weight was 71.7 kilograms, and height was 66 inches.  Patient had numerous surgeries relating to ostomy in 1996 which were catastrophic with many infections. In 2019, patient changed from J-pouch to ostomy. patient had pericarditis in 2020 which ended up in emergency room (ER). Concurrent conditions included: sulfa allergy (burning sensation all over his body), alcohol user (very rarely), and non smoker, and patient did not have any drug abuse/illicit drug use. The patient received covid-19 vaccine ad26.cov2.s (suspension for injection, route of admin not reported, batch number: Unknown, expiry: Unknown) dose was not reported, 1 total, administered on left arm on 02-APR-2021 for prophylactic vaccination. The batch number was not reported and has been requested. No concomitant medications were reported. On 09-AUG-2021, patient had headache in the evening along with chills (sheet wet), fever of 104 degrees F and body temperature was going up and down (suspected covid-19 infection and suspected clinical vaccination failure). On 10-AUG-2021, the next morning, patient had two swabs for covid which both came back negative. His symptoms continued and also included fatigue, body ache, pain, some vomiting and nonproductive cough when talked to the degree that his chest hurt when he coughed. On 13-AUG-2021, patient went to hospital and was there for 6-7 hours. They did swab, blood work, X-ray, metabolic panel. They said there were no flu and no covid and sent him home with the instruction to rest and to have fluids. On 13-AUG-2021, Laboratory data included: Alanine aminotransferase (NR: 12 - 78) 111 U/L, Alkaline phosphatase (NR: 45 - 117) 269 U/L, Aspartate aminotransferase (NR: 15 - 37) 85 U/L, Atypical lymphocytes (NR: 0 - 0) 7.7 %, Bilirubin total (NR: 0.2 - 1.0) 1.4 mg/dL, Body temperature (NR: not provided) 101 F, Chest X-ray (NR: not provided) no flu and no covid (revealed the lungs were clear and the heart was of normal size. No change from 19-MAR-2020), Creatinine (NR: 0.6 - 1.3) 1.4 mg/dL, Lymphocyte count (NR: 28 - 48) 13.7 %, Mean platelet volume (NR: 6.0 - 10.0) 10.2 fL, Neutrophil count (NR: 34 - 64) 70.9 %, Pulse rate (NR: not provided) 129, Respiratory viral panel (NR: not provided) No abnormal detection, Sodium (NR: 136 - 145) 133 mEq/L, and Viral swab (NR: not provided) No flu and no covid. On 13-AUG-2021, procalcitonin and urinalysis, macroscopic urinalysis was performed whose results were within normal range. Patient was given Tylenol and sodium chloride. On 18-AUG-2021, patient went back ER and came out morning at 5.00. On 18-AUG-2021, influenza A PCR, influenza A PCR, blood smear and SARS-COV-2 PCR (COVID-19) test were in progress and results were not known. They also did CT Scan, full metabolic panel, PCR, CBC, D-Dimer, which the patient did not have the results but was told they were okay. Patient had elevated liver function tests. They also said there were no clot in the lung but they did not have the results. They gave him Toradol, Zofran, and Ns (Normal Saline) in the hospital and sent him home with a prescription for Naprosyn. The patient's symptoms were continuing. The patient was under assumption that they tested for covid and not sure whether they tested for antibodies.  The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The patient had not recovered from suspected covid-19 infection, and the outcome of suspected clinical vaccination failure was not reported. This report was serious (Other Medically Important Condition). This report was associated with product quality complaint: 90000190611; Sender's Comments: V0:20210841156-COVID-19 VACCINE AD26.COV2.S-Suspected clinical vaccination failure. This event(s) is considered not related. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There are other factors more likely to be associated with the event(s) than the drug. Specifically: SPECIAL SITUATIONS 20210841156-COVID-19 VACCINE AD26.COV2.S-Suspected COVID-19 infection. This event(s) is considered unassessable. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There is no information on any other factors potentially associated with the event(s).