Nonenveloped, human pathogen belonging to the family of Polyomaviridae. Also known as human papillomavirus (HPV). The pathogen may cause benign genital warts, but also cervical cancer. Potential iatrogenic (see also Iatrogenic illness) sources of transmission include ultrasonic heads of probes for vaginal examination. In Germany, polyomavirus (SV 40) serves as test virus for virucidal efficacy testing of disinfectants.