Sexually transmitted diseases, commonly referred to as STDs, are incredibly common here in the U.S. and around the world. In fact, about 1 in 2 people who have sex will contract at least one STD or sexually transmitted infection by age 25. And almost all sexually active people will become infected with an STD at some point during their lives.

In the U.S. and throughout the world, just four disease account for most new infections — chlamydia, gonorrhea, syphilis and trichomoniasis. But by far the most common STD is human papillomavirus. Researchers estimate that nearly 80 million Americans are currently infected with HPV, more than many other STDs, including chlamydia, herpes, HIV, syphilis and gonorrhea, combined.

Rates of several common STDs have been on a steady increase in the U.S. over the past few years. In fact, gonorrhea, chlamydia, and primary and secondary syphilis all have seen infection rates increase nationally for the past four consecutive years. According to data from the federal Centers for Disease Control and Prevention, since 2013, the U.S. chlamydia rate has increased nearly 20%, the gonorrhea rate has jumped more than 60% and the rate of primary and secondary syphilis has risen by nearly 75%.

Over that same time period, every state saw its gonorrhea rate rise, and the vast majority posted increases to their chlamydia and syphilis rates as well. Between 2013 and 2017, the average state-level increase to the chlamydia rate was 18.6%, with New Hampshire’s 40.2% increase topping the list of rising rates. One state, West Virginia, saw the chlamydia rate fall, as the state cut its rate by 18.4%.

Wyoming’s 375% increase in the gonorrhea rate since 2013 was the nation’s largest, while the smallest increase in gonorrhea was in Pennsylvania, where the rate rose by only 10%. Still, 15 states had gonorrhea rate increases of more than 100%, and three (Wyoming, Idaho and New Hampshire) saw gonorrhea rates climb by more than 300%.

Rates of primary and secondary syphilis, which is when the disease is most contagious, fell in only three states — Michigan, Iowa and South Dakota — and climbed by an incredible 820% in Montana, though the increase is partly due to the fact that the primary and secondary syphilis rate in Montana in 2013 was less than 1 per 100,000 people, making it the lowest rate in the nation that year.

Not all sexually transmitted diseases are on the rise, however. In fact, the U.S. has seen newly diagnosed cases of HIV drop in recent years, and estimated infection rates of herpes have fallen as well, which means progress is possible.

Chipping away at the prevalence of STDs means educating yourself about your risk and the trends in sexually transmitted infections where you live. Explore the pages below to learn more about the prevalence of many common sexually transmitted diseases in your state or hometown.

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