Well, that didn't take long.

Exactly 6 months after warning, in a major medical journal, that gonorrhea was becoming untreatable by the last two drugs commonly used against it, the Centers for Disease Control has taken one of those drugs off the table, leaving just one antibiotic available to treat the disease.

In a bulletin published today, the public health agency says that data from the national Gonococcal Isolate Surveillance Project shows a high enough percentage of resistance to the oral cephalosporin cefixime that "CDC no longer recommends cefixime at any dose as a first-line regimen for treatment of gonococcal infections." Instead, it says, physicians should administer a single dose of injectable ceftriaxone, accompanied by some additional oral drugs.

This has been coming for a while, but it is still unnerving news. It means that the entire structure of sexually transmitted disease control in the United States — single doses of drugs given in single outpatient-clinic visits — now hangs on this one remaining drug. If ceftriaxone also becomes ineffective, then STD treatment will instead become a matter of giving drugs by IV: slower, more complicated, more expensive, and likely more difficult to access.

In fact, being forced to use ceftriaxone instead of cefixime already makes gonorrhea treatment more complicated, because while pills can be dispensed by any clinic worker once they have been prescribed, an injection must be given by a licensed health professional.

But that's nothing compared to what might happen if resistance in gonorrhea gets worse, and the remaining drug becomes not usable. In a statement also released today, the National Coalition of STD Directors (whose members run state STD programs) said:

...the following could occur as a result of resistance over the next seven years: gonorrhea incidence could increase four-fold to nearly 6 million additional cases; nearly 800 additional HIV infections; a quarter million cases of pelvic inflammatory disease in women; and ultimately, over that seven year window, cost over three-quarter of a billion dollars in lifetime medical costs.

Along with the recommendation to stop using cefixime, the CDC also released a detailed Cephalosporin-Resistant Gonorrhea Response Plan (cefixime and ceftriaxone belong to a class of antibiotics known as "third-generation cephalosporins") and a brief fact sheet that sums up the plan's top points. Reading between the lines, what the plan says is that uncomplicated, inexpensive gonorrhea treatment may already be over. The CDC's recommendations include bringing patients who have persistent symptoms back for a second visit to make sure they are cured, changing the tests that are done to prove a cure, and scaling up personnel and lab capacity at state public-health labs so that the additional burden of new tests can be processed.

I've been covering the rise of resistance on gonorrhea for more than a year here; here are all the past posts.

Cite: Update to CDC's Sexually Transmitted Diseases Treatment Guidelines, 2010: Oral Cephalosporins No Longer a Recommended Treatment for Gonococcal Infections. MMWR, August 10, 2012 / 61(31);590-594.

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