The Centers for Disease Control and Prevention announced there were nearly 2.3 million cases of chlamydia, gonorrhea and syphilis diagnosed in the U.S. last year, record-high rates for the three sexually transmitted diseases.
The figures surpassed the previous record of STD diagnoses set in 2016 by more than 200,000 cases and marked the fourth consecutive year of sharp increases.
They also raised renewed concerns about the threat of the emergence of drug resistance that could eventually garner gonorrhea "untreatable." In the CDC report, released Tuesday, officials said gonorrhea has become resistant to nearly every class of antibiotics used to treat it, except to ceftriaxone, the only remaining highly effective antibiotic to treat gonorrhea in the U.S.
According to the report, gonorrhea diagnoses increased 67% from 333,004 in 2013 to 555,608 cases in 2017 and nearly doubled among men (from 169,130 to 322,169).
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The new CDC findings show emerging resistance to azithromycin is now on the rise in laboratory testing—with the portion of samples that showed emerging resistance to azithromycin increasing from 1% in 2013 to more than 4% in 2017. In 2015, CDC began recommending health care providers prescribe a single shot of ceftriaxone accompanied by an oral dose of azithromycin to people diagnosed with gonorrhea. Azithromycin was added to help delay the development of resistance to ceftriaxone.
"We expect gonorrhea will eventually wear down our last highly effective antibiotic, and additional treatment options are urgently needed,” said Gail Bolan, M.D., director of CDC’s Division of STD Prevention. “We can’t let our defenses down—we must continue reinforcing efforts to rapidly detect and prevent resistance as long as possible.”
There has not yet been a confirmed treatment failure in the U.S. since the dual therapy approach was implemented.
The finding adds concerns that azithromycin-resistant genes in some gonorrhea could cross over into strains of gonorrhea with reduced susceptibility to ceftriaxone—and that a strain of gonorrhea may someday surface that does not respond to ceftriaxone.
Beyond concerns of patient safety, the problem of antibiotic resistance is a costly one. A study published in Health Affairs earlier this year estimated that antibiotic resistance adds more than $1,000 to the cost of treatment for a single patient, costing the system well over $2 billion per year.
A report from the World Health Organization found that a lack of new antibiotics under development to combat drug-resistant superbugs has drastically reduced treatment options, and CDC statistics indicate that 23,000 people die of antibiotic-resistant infections each year in the United States.
The data released Tuesday also showed primary and secondary syphilis diagnoses increased 76% from 17,375 to 30,644 cases. Gay, bisexual and other men who have sex with men made up almost 70% of primary and secondary syphilis cases where the gender of the sex partner is known in 2017. Chlamydia remained the most common condition reported to CDC. More than 1.7 million cases were diagnosed in 2017, with 45% among 15- to 24-year-old females.