Scientists at the University of Pittsburgh have linked a previously unknown virus with Merkel cell carcinoma, the most aggressive form of skin cancer. The new virus, called Merkel cell polyoma virus, will be a part of the Polyomaviridae family. The polyoma virus is the seventh virus linked to human cancers, Dr. Moore and Dr. Fauci said. The others, in addition to the Kaposi's sarcoma virus, are hepatitis B and C viruses, linked to liver cancer; papilloma virus, to cervical cancer; Epstein-Barr virus, to cancer of the nose and pharynx and to Burkitt's lymphoma; and HTLV-1, or human T-cell leukemia virus 1.
While further study needs to confirm the virus as the causative agent, its infection is so strongly linked to cancer incidence that it is likely to play an important role in the carcinogenesis.