<P> In 2008, it was estimated that 500 million people were infected with either syphilis, gonorrhea, chlamydia or trichomoniasis . At least an additional 530 million people have genital herpes and 290 million women have human papillomavirus . STIs other than HIV resulted in 142,000 deaths in 2013 . In the United States there were 19 million new cases of sexually transmitted infections in 2010 . </P> <P> In 2010, 19 million new cases of sexually transmitted infections occurred in women in the United States . A 2008 CDC study found that 25--40% of U.S. teenage girls has a sexually transmitted disease . </P> <P> AIDS is among the leading causes of death in present - day Sub-Saharan Africa . HIV / AIDS is transmitted primarily via unprotected sexual intercourse . More than 1.1 million persons are living with HIV / AIDS in the United States, and it disproportionately impacts African Americans . Hepatitis B is also considered a sexually transmitted disease because it can be spread through sexual contact . The highest rates are found in Asia and Africa and lower rates are in the Americas and Europe . Approximately two billion people worldwide have been infected with the hepatitis B virus . </P> <P> The first well - recorded European outbreak of what is now known as syphilis occurred in 1494 when it broke out among French troops besieging Naples in the Italian War of 1494--98 . The disease may have originated from the Columbian Exchange . From Naples, the disease swept across Europe, killing more than five million people . As Jared Diamond describes it, "(W) hen syphilis was first definitely recorded in Europe in 1495, its pustules often covered the body from the head to the knees, caused flesh to fall from people's faces, and led to death within a few months," rendering it far more fatal than it is today . Diamond concludes, "(B) y 1546, the disease had evolved into the disease with the symptoms so well known to us today ." Gonorrhoeae is recorded at least up to 700 years ago and associated with a district in Paris formerly known as "Le Clapiers". This is where the prostitutes were to be found at that time . </P>

What is the number 1 sexually transmitted disease