The U.S. Centers for Disease Control (CDC) released data revealing that 20 million new sexually transmitted infections (STIs) are diagnosed each year nationwide, costing some $16 billion in taxpayer funds. Half of the 20 million new infections affect people ages 15 to 24 - who only make up a quarter of the population, according to the statistics. Human papillomavirus (HPV) tops the list as the most common infection followed by chlamydia, gonorrhea, syphilis, herpes, hepatitis B, HIV and trichomoniasis. The number of new infections in the country has been growing over the last couple decades, leading one CDC researcher to declare that the U.S. is facing an “ongoing, severe STI epidemic.” There were 15 million new infections reported in 1996 and 18.9 million reported in 2000.