When the bacteria enter the urethra, they can make their way up into the bladder and cause an infection. In the VIP June 19, Avoid prolonged exposure to moisture in the genital area by not wearing nylon red tube having sex or wet swimsuits. Call your doctor's office or clinic immediately. When bacteria get into the bladder or kidney and multiply in the urine, a UTI can result. This is the reason why females who are sexually active often red tube having sex UTIs UTIs are not contagious, so you can't catch a urinary tract infection from someone else. Only your health care provider can treat urinary tract infections. In the case of a kidney infection, a doctor may prescribe pain medication. There are several ways people may be able to prevent urinary tract infections.