Sexually transmitted diseased in the U.S. are at record highs, according to the Atlanta-based Centers for Disease Control and Prevention.

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The agency reported 2.29 million new cases of chlamydia, gonorrhea and syphilis — three common but treatable STDs — last year, based on preliminary data.

That surpasses the 2016 record by more than 200,000 cases, and marks the fourth consecutive year of increases.

"We are sliding backward," Jonathan Mermin, director of CDC's National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, said in a news release. "It is evident the systems that identify, treat, and ultimately prevent STDs are strained to near-breaking point."

Since 2013, gonorrhea diagnoses increased 67 percent overall, with nearly double reported among men and sharp increases reported among women.

Gay, bisexual and other men who have sex with men accounted for 70 percent of the 30,644 cases of primary and secondary syphilis, which increased 76 percent since 2013.

More than 1.7 million chlamydia cases were reported in 2017, 45 percent of which were among 15- to 24-year-old females.

Last year, Georgia ranked among the top five states in America with the highest rates of chlamydia, gonorrhea and syphilis, according to a CDC report.

All three diseases are treatable via antibiotics, but many cases go untreated, "which can lead to severe adverse health effects that include infertility, ectopic pregnancy, stillbirth in infants, and increased HIV risk,"
according to the CDC.

Previous research also suggests socioeconomic factors, stigma, discrimination and drug use may contribute to STD increases.

In the Aug. 28 announcement, the CDC also addressed concerns about antibiotic resistant gonorrhea.

For now, the agency recommends a two-drug combination to preserve the last highly effective antibiotic: a single shot of ceftriaxone plus an oral dose of azithromycin. But lab tests show there may be rising resistance to azithromycin. There may also ultimately be a strain that will no longer respond to ceftriaxone.

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"We expect gonorrhea will eventually wear down our last highly effective antibiotic, and additional treatment options are urgently needed," Gail Bolan, director of CDC's Division of STD Prevention, said. "We can't let our defenses down — we must continue reinforcing efforts to rapidly detect and prevent resistance as long as possible."