SUSPECTED COVID-19 INFECTION; BLOOD WITH NO FECAL MATTER COMING OUT OF THE RECTUM; BLOOD WITH NO FECAL MATTER COMING OUT OF THE RECTUM; SUSPECTED CLINICAL VACCINATION FAILURE; MILD ACHINESS; MILD TIREDNESS; This spontaneous report received from a patient concerned a 69 year old female of an unspecified race and ethnic origin. The patient's weight was 148 pounds, and height was 65 inches. The patient's past medical history included, gastric ulcer (no medication received) and concurrent conditions included, allergy of shell fish, spinach, kale, dark leafy vegetables, contrast dye and antibiotics. She was alcohol user (very rarely, less than once a month) and non-smoker. She had no history of drug abuse or illicit drug use. She experienced drug allergy when treated with Cipro (ciprofloxacin) used for an unknown indication.  The patient received Covid-19 vaccine ad26.cov2.s (suspension for injection, route of admin not reported, batch number: 1805025, expiry: 25-MAY-2021) dose was not reported, frequency one total administered on 12-MAR-2021 for prophylactic vaccination. Patient did not receive any medication. On 12-MAR-2021 (after vaccination), the patient experienced mild achiness and mild tiredness that lasted for a day. On 22-JUL-2021, she performed a Covid-19 test at home, result was positive. Another Covid-19 test was performed at the hospital and she was diagnosed with Covid-19 (suspected Covid-19 infection and suspected clinical vaccination failure). On 23-JUL-2021, she was hospitalized for 2.5 days. On an unspecified date, the symptoms of Covid-19 infection had hit the intestinal tract for 3 days. She had blood with no fecal matter coming out of the rectum (9 events of a lot of blood coming out) and couldn't move because she was in much pain. Her gastric doctor stated that the delta variant might have hit the intestinal tract. She also, had lingering cough, but it did not affect her oxygen levels and remained 100% throughout her hospitalization. Her computerized tomography (CT) scan and blood tests, the results were not reported.  The action taken with Covid-19 vaccine ad26.cov2.s was not applicable. The patient recovered from blood with no fecal matter coming out of the rectum, and blood with no fecal matter coming out of the rectum on JUL-2021, and mild achiness, and mild tiredness on 13-MAR-2021, was recovering from suspected covid-19 infection, and the outcome of suspected clinical vaccination failure was not reported. This report was serious (Hospitalization Caused / Prolonged, and Other Medically Important Condition).; Sender's Comments: V0: 20210835203 -COVID-19 VACCINE AD26.COV2.S- blood with no fecal matter coming out of the rectum (rectal bleeding, constipation), suspected COVID-19 infection. This event is considered unassessable. The event 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. 20210835203-COVID-19 VACCINE AD26.COV2.S-Suspected clinical vaccination failure. This event is considered not related. The event 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 than the drug. Specifically: SPECIAL SITUATIONS