This fact sheet explains two analyses published by CDC that examined the severe human and economic burden of sexually transmitted infections (STIs) in the United States. The new estimates indicate that there are about 20 million new U.S. infections each year, half of which occur among the nation’s youth. Also, there are more than 110 million STIs in the United States, which cost the health care system approximately $16 billion in medical costs alone. The information sheet explains how CDC developed its new estimates, the significant costs of STIs to the US healthcare system, and how to fight STIs through prevention, diagnosis, and prompt treatment. The sheet also includes CDC’s STI screening recommendations.