Hi. Thanks for your query. Noted the history and understood your concerns. History of stomach flu in you and family members, vomiting and diarrhea, back and hip pain indicate the possibility of the following: It can be stomach flu as you have mentioned. It can be food poisoning as all the family members too got affected and you had red blood in stool hence can be infective. I would advise you the following in such a circumstance: Get the stool tests which will tell us whether the diarrhea and other symptoms are due to bacterial infection or a viral/flu infection. Also check the blood, particularly for CBC, urea, creatinine, liver function tests. If bacterial, a course of an antibiotic and metronidazole along with probiotics can help to resolve the issue. Antibiotics have no role in in flu. But either of the general outline of management remains same: Maintenance of fluid and electrolyte balance. Good nutrition. Probiotics, yogurt, bananas and activated charcoal help a lot in recovery. Also get all the family members the similar clinical evaluation, blood and stool tests and treatment as required.