Clinically, the chance of HIV transmission through sharing toothpaste is relatively small. For HIV patients and HIV-infected patients, HIV is mainly found in their blood, semen, vaginal secretions, chest and abdominal fluids, breast milk and cerebrospinal fluid. Their saliva often contains negligible amounts of HIV, so eating and kissing together will not usually lead to HIV transmission. Some patients who have obvious or recurrent mouth ulcers and blood every time they brush their teeth can be infected by sharing toothbrushes, but sharing toothpaste is often less of a problem.