text: Some, yes. For example, a new vaccine is now promising to significantly reduce the cases of cervical cancer. It is estimated that as many as 2/3 of the cases of cervical cancer are caused by the human papilloma virus (HPV). It follows, therefore, that reducing the incidence of infection from HPV will also reduce the incidence of cervical cancer. Viruses as well as bacteria have been implicated in a number of other cancers. Heliobacter pylori (H Pylori) infections in the gastrointestinal tract have been linked to certain lymphomas of the gut. \n\nViruses sometimes work indirectly in causing cancers. For example, both AIDS and hepatitis are caused by viruses and they subsequently weaken the body and make it more susceptible to cancer. AIDS destroys the immune system and makes it harder for the body to ward off viruses, bacteria, and cancer cells.  Sadly, people suffering from AIDS are at a much higher risk for a multitude of cancers which the body would normally be able to protect itself from (including viruses like Epstein-Barr and certain herpesviruses that are themselves linked to cancer). Hepatitis increases the likelihood of liver cancer.\n\nHopefully, researchers will one day find an effective vaccine against viruses that are in one way or another linked to cancer.