LACUNAR INFARCTION; ATAXIA; DIZZINESS; FALL; GAIT DISTURBANCE; HEADACHE; COMPUTERISED TOMOGRAM HEAD ABNORMAL; PRESYNCOPE; PAIN; CHEST PAIN; ELECTROCARDIOGRAM; IMAGING PROCEDURE; LABORATORY TEST; COVID-19; SARS-COV-2 TEST POSITIVE; This spontaneous report received from a health care professional via a Regulatory Authority Vaccine Adverse Event Reporting System concerned a 61 year old male of unspecified race and ethnic origin. The patient's height, and weight were not reported. The patient's past medical history included: stents, and concurrent conditions included: COPD (Chronic Obstructive Pulmonary Disease), arthritis, and CAD (Coronary Artery Disease). The patient received covid-19 vaccine ad26.cov2.s (suspension for injection, route of admin not reported, batch number: 206A21A expiry: UNKNOWN) dose was not reported, 1 in total, administered on 11-MAY-2021 for an unspecified indication. Age at time of vaccination 61 years old. Concomitant medications included alprazolam, atorvastatin, and clopidogrel bisulfate. On 21-JUL-2022, It was reported that, the patient with a history of high cholesterol coronary artery disease and stents who presented to the emergency department with a complaint of 4 to 5 days of dizziness. It was reported that, the Patient described the dizziness as a combination of presyncope and ataxia. The patient had been walking into things and falling into things (gait disturbance) for the last 4 days and described symptoms of a headache that goes from the left posterior neck and radiates up the left side of his head sharp pain moderate in intensity. On the day of reporting, the patient had some sharp left anterior chest pain that lasted only a few minutes and spontaneously subsided.  The physician took over the care of the patient and reviewed all the lab results EKG (Electrocardiogram) and radiological findings. The CT (Computed Tomography) scan of the head revealed a lacunar infarct of undetermined age in the left caudate nucleus. The patient tested positive for the COVID-19 infection. It was decided to admit the patient for further work-up The physician requested a tele-neurology consultation before accepting the patient. The patient was evaluated by physician (neurologist) through the tele-neurology system. The patient was advised a stroke work-up. and was hospitalized (date unspecified). The patient was hospitalized for 2 days and it was unsure if the patient was discharged from the hospital. The latency of the events was reported as 436 days. On 21-JUL-2022, Laboratory data included: Computerised tomogram head abnormal Abnormal, Electrocardiogram Not reported, Imaging procedure Not reported, Laboratory test Not reported, and SARS-CoV-2 test positive Positive. Laboratory data (dates unspecified) included: COVID-19 virus test Positive, CT brain scan a lacunar infarct of undetermined age in the left caudate nucleus, EKG Not reported, and X-ray Not reported. It was reported that the patient was administered with home medications. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The patient had not recovered from ataxia, covid-19, chest pain, computerised tomogram head abnormal, dizziness, electrocardiogram, fall, gait disturbance, headache, imaging procedure, laboratory test, lacunar infarction, pain, presyncope, and sars-cov-2 test positive. This report was serious (Hospitalization Caused / Prolonged). This report was associated with product quality complaint: 90000245714. The suspected product quality complaint has been confirmed to be the reported allegation could not be determined. a manufacturing related root cause could not be identified. based on the PQC evaluation/investigation performed.  Additional information was received from department on 08-SEP-2022. The following information was updated and incorporated into the case narrative: PQC investigation result was added.; Sender's Comments: V1:Follow up information in this version updates,PQC investigation result was added. This updated information does not change the causality of the previously reported events.  20220815847- covid-19 vaccine ad26.cov2.s-Lacunar infarction, Ataxia, Dizziness, Fall, Gait Disturbance, Headache, Computerised tomogram head abnormal, Presyncope, Pain, Chest pain, Electrocardiogram, Imaging procedure, Laboratory test. The event(s) shows an incompatible temporal relationship. Therefore, this event(s) is considered not related. (Temporal relation was considered as incompatible for events as the onset date is at an interval of 14 months after date of vaccination. The events are confounded by the medical history Coronary artery disease, COPD, high cholesterol, arthritis and stent procedure)  20220815847- covid-19 vaccine ad26.cov2.s - Covid -19, SARS Cov 2 test positive. The event(s) shows an incompatible temporal relationship. Therefore, this event(s) is considered not related. (Temporal relation was considered as incompatible for events as the onset date of Covid 19, SARS Cov 2 test positive is at an interval of 14 months after date of vaccination.)