BRAIN FOG; HEAVY SWEATING EPISODES; INCREASED HEART RATE; CONFIRMED CLINICAL VACCINATION FAILURE; CONFIRMED COVID-19 INFECTION; This spontaneous report received from a patient concerned a 67 year old male. The patient's height, and weight were not reported. The patient's past medical history included: heart valve replacement (The patient was on cholesterol and blood pressure medications), and concurrent conditions included: stage 1 chronic obstructive pulmonary disease (Emphysema), and coronary artery disease, and other pre-existing medical conditions included: The patient had no known allergies. The patient previously received with covid-19 vaccine ad26. cov2.s (dose number in series 1) (suspension for injection, route of admin not reported, batch number: 1805029, expiry date: MAY-2021) dose was not reported, 1 total, administered on right arm on 14-MAR-2021 for prophylactic vaccination. No adverse events reported following vaccination with first dose of covid-19 vaccine ad26. cov2.s and patient also stated that, he did not experience any serious events after covid-19 primary vaccine and was very happy about that (dose number in series 1). The patient received additional booster dose of covid-19 vaccine ad26.cov2.s (dose number in series 2) (suspension for injection, route of admin not reported, batch number: 212A21A, expiry: 20-MAY-2022) dose was not reported, 1 total administered on right arm on 04-NOV-2021 for prophylactic vaccination. Age at time of vaccination 66 years old. No concomitant medications were reported. On 31-MAY-2022, the patient stated that he was feeling odd with a serious case of sinus, tickle sore-throat, heavy chest and labored breathing (Confirmed covid-19 infection) (dose number in series 2).  On 01-JUN-2022, the patient was feeling tired, had brain fog, heavy sweating episode, nausea, headache and increased heart rate (100/110, and was normal in 70 BPM (Beats Per Minute). He went to get checked out and was diagnosed with positive covid (visited to physician office). Laboratory data included: COVID-19 virus test (NR: not provided) Positive. The patient was not sure about the type of test they did for him (said it was a swab in the nostril and throat) (confirmed clinical vaccination failure) (dose number in series 2). The patient also stated that he did not experience any serious event after J and J booster and was very happy about that (dose number in series 2). The patient was also prescribed with non-company an experimental antiviral drug Paxlovid (form of admin, route of admin, batch number and expiry date were not reported) dose was not reported, administered first dose on an unspecified date for an unspecified indication. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The outcome of the confirmed covid-19 infection, brain fog, heavy sweating episodes, increased heart rate and confirmed clinical vaccination failure was not reported. This report was serious (Other Medically Important Condition). This report was associated with a product quality complaint: 90000233994.; Sender's Comments: V0. 20220606592-covid-19 vaccine ad26. cov2.s -Confirmed clinical vaccination failure . 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. Therefore, this event(s) is considered not related.