SHORT ANSWERS TO HARD QUESTIONS ABOUT HPV. “This week, the federal government reported that nearly half of Americans between the ages of 18 and 59 are infected with genital human papillomavirus — some strains of which can cause deadly cancer. The report, by the National Center for Health Statistics, notes that HPV is the most common sexually transmitted infection in the United States. It also said that some high-risk strains infected 25 percent of men and 20 percent of women, and cause about 31,000 cases of cancer each year.”