Genus Papillomavirus:
Human Papillomavirus
HPV is currently the most important papovavirus. Seventy strains of Human Papillomavirus have been identified so far. These viruses are known for their role in causing warts (both common warts and genital warts) as well as their association with cancer. Most people are infected with some strain of HPV in their lives.
Genus Polyomavirus
JC Virus
This virus, found only in humans, and is spread throughout the human population. Infection rarely results in diseas, except in the case of the immunosuppressed. JC virus leads to progressive multifocal leukoencephalopathy, one of the leading causes of death for those with HIV, and persistent urinary tract infections. JC are the initials of the first patient with the disease. Most people are subclinically infected with the virus in childhood.
BK Virus
BK virus was isolated in 1971 in a renal transplant patient. It, too, is often found in the urinary tract of immunosuppressed individuals, but BK virus is not associated with progressive multifocal leukoencephalopathy (PML). Infection tends to occur early in life. Both BK virus and JC Virus are linked to cancer.