The night before Valentine’s Day, a day devoted to all things love and romance, the Centers for Disease Control (CDC) announced the rather un-romantic statistic that the U.S. is harboring some 110 million cases of sexually transmitted diseases (STDs or SDIs). That comes out to almost 20 million new infections each year, and the problem appears to be getting worse. The announcement came as a result of two studies that the agency just published.

Human papillomavirus (HPV) takes home first prize for popularity, followed by chlamydia, gonorrhea, syphilis, herpes, hepatitis B, HIV, and trichomoniasis (in no particular order). More than half of the infections occur in the county’s young adult population, affecting those between the ages of 15 and 24.

The lead author of one of two studies says that the nation is facing, "an ongoing, severe, STI epidemic."

STDs offer more than stigma and discomfort, they can be the source of severe and long-term health problems. Not only do STDs increase a person’s risk for HIV infection, they can result in vexing health complications. Untreated chlamydia or gonorrhea, for instance, can put a woman at increased risk of chronic pelvic pain and potentially fatal ectopic pregnancy, as well as increased risk of infertility. HPV accounts for the majority of newly acquired STDs, and while 90 percent of these infections will go away on their own, the tenacious ones can potentially lead to serious diseases such as cervical cancer.

And then there’s the economic impact: The diseases collectively require nearly $17 billion a year to treat.

Four of the infections - chlamydia, gonorrhea, syphilis, and trichomoniasis - respond well to treatment and can be cured if discovered early, yet many of these cases go undetected because they often are not accompanied by any symptoms. The CDC urges all people who are sexually active to get STD screening and prompt treatment if necessary.

All of the STDs with a role in this epidemic are preventable. To protect oneself against STDs, the CDC recommends several options: Abstaining from sex, reducing the number of sexual partners, and consistently and correctly using condoms.

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CDC: Sexually transmitted diseases have become a severe epidemic
Treating the country's 110 million STDs comes with a price tag of $16.7 billion a year.