Urinary tract infections are caused by bacteria entering the urinary tract through the urethra. Common symptoms include a frequent and painful urge to urinate, pain during urination, and urine that may be bloody. Diagnosis involves testing a urine sample for bacteria and white blood cells. Treatment usually involves a course of antibiotics over 7-10 days. Good hygiene, drinking fluids, urinating when needed, and cranberry supplements can help prevent recurrent urinary tract infections.