HPV is the acronym for the human papillomavirus. One type of HPV virus is the cause of genital warts. Other types of HPV cause warts on the hands or feet; still others cause no signs or symptoms at all. Health experts estimate that there are more cases of genital HPV infection than any other sexually transmitted disease in the United States. According to the American Social Health Association, approximately 5.5 million new cases of sexually transmitted HPV infections are reported every year. At least 20 million people in this country are already infected.