For the first time in its history, the Centers for Disease Control and Prevention is categorizing drug-resistant superbugs by threat level. On Monday, the CDC issued its highest level of warning for a drug-resistant strain of gonorrhea—saying the sexually transmitted disease is an "urgent threat" to the health of Americans.
"We've been raising this issue for some time, and the CDC just confirms how serous the problem is," said William Smith, executive director of the National Coalition of STD Directors, a nonprofit group that provides services and programs to fight sexually transmitted diseases and works with the CDC.
"There's no question gonorrhea is developing resistance to every drug created to fight it," Smith said.
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Some 820,000 cases of gonorrhea are reported in the U.S. every year, making it the second most reported communicable disease behind another sexual disease, chlamydia. According to the CDC, an estimated 246,000 of those gonorrhea cases are of the drug-resistant strain.
The term superbug is commonly used to describe any microorganism that is resistant to at least one or more commonly used antibiotics.
The CDC says that if a drug-resistant strain of gonorrhea becomes widespread over a 10-year period, there will be an estimated 75,000 additional cases of pelvic inflammatory disease—which causes infertility. And there would be hundreds of additional HIV cases.
The CDC estimates that direct medical costs if the strain spreads will be $235 million over the 10 years, but that costs would likely be even higher due to case management and patient follow-ups with doctors.
"We can pay the costs of this going forward or do the investing now," said Smith, whose group has called for some $54 million in spending by Congress for proper diagnosis and development of an antibiotic to treat the strain.
So far, the strain of gonorrhea, called Neisseria gonorrhoeae, is showing resistance to the current and strongest antibiotic in use, called ceftriaxone, which is administered by a painful injection, Smith said.
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"The strain is tricky," said Smith. "And it's asymptomatic, meaning people might not know they have it because they are not showing symptoms for it. And we don't have the diagnostics to know what type of mutations are happening."
To help develop more antibiotics for resistant strains of all bacteria, Congress passed the Gain Act in 2012. The law provides an additional five years of market exclusivity to pharmaceutical companies for new drugs while giving the drugs priority with the Food and Drug Administration for quicker review and approval.
Much of the current research in antibiotics is being done by small biotech companies. A new drug, solithromycin, is being tested for gonorrhea by Cempra. The drug is in phase two of development, with several more phases needed before it's presented to the FDA for approval.
According to the CDC, at least 2 million people in the U.S. become infected with bacteria that are resistant to antibiotics, and at least 23,000 people die each year as a direct result of those infections. Many more people die from other conditions that were complicated by an antibiotic-resistant infection.
The concerns are that overuse of antibiotics in humans and animals is making bacteria drug-resistant. The CDC found that up to half of the antibiotics prescribed to people are unnecessary. Researchers also believe antibiotics to treat farm animals are often overused.
Besides gonorrhea, two other strains of drug-resistant bacteria are listed as "urgent threats." Clostridium difficile causes life-threatening diarrhea, and carbapenem-resistant Enterobacteriaceae, or CRE, is also life threatening and mostly found in hospital patients.
For treatment of gonorrhea, the CDC now recommends only ceftriaxone plus either azithromycin or doxycycline as a first-line treatment. The full emergence of a ceftriaxone-resistant strain would greatly limit treatment options and could cripple gonorrhea control efforts, says the CDC.
And for those worried about contracting the drug-resistant strain of gonorrhea, the NCSD's Smith had some simple advice.
"Use a condom if you're not in a monogamous relationship, and get yourself tested on a regular basis. But nothing is 100 percent guaranteed for protection," he said.
—By CNBC's Mark Koba. Follow him on Twitter @MarkKobaCNBC