Antibiotic resistance may often seem like a distant threat—something we don't need to worry about right now. You may not even remember the last time you were given antibiotics. But if you cast your mind back to memories you've tried to erase, you may well recall being prescribed them for that awkward itch in that awkward place, which thankfully cleared up and disappeared shortly after. Imagine if it had been harder to treat? It soon could be.
Worryingly, gonorrhoea has already become resistant to most of the antibiotics that have been used to treat it over the past 30 years. Now the US Center for Disease Control and Prevention (CDC) has named it an "urgent public health threat." That's because we pretty much rely on antibiotics to treat the problem, but they're quickly being rendered ineffective.
A new study published this week in the CDC journal Emerging Infectious Diseases describes how few treatments are left and goes on to explain that antibiotic resistance leads to an increase in cases of "the clap." We've been warned about this before, and now things are looking increasingly desperate.
The form of gonorrhoea that people catch today isn't actually the same strain that previous generations have been infected with, because it's become resistant to all but a couple of the antibiotic treatment options on offer: sulfonilamides, penicillin, tetracycline, and fluoroquinolones, such as ciprofloxacin. Unfortunately, becoming resistant doesn't alter the symptoms—you can still get a yellow-green discharge, swollen testicles/grotty vagina, pain during sex, and itching. Not exactly symptoms you want to leave untreated.
When antibiotics are used frequently, new strains of bacteria start appearing. Some of these strains will not be denatured by the antibiotic; by Darwinian principles, those will be the ones that survive, while the weaker strains are banished from existence. The more antibiotics are used, the more resistant strains start to emerge.
Our frequent use of antibiotics (we use them for everything, even feeding them to the animals that we later go on to eat) has meant that more resistant strains have appeared, but rather worryingly we're not introducing new drugs with the same kind of haste. On the contrary. The rate at which new antibiotics are being developed is actually decreasing, while resistant strains are becoming more and more common.
In this new study, researchers looked at long-term surveillance data of more than 17 US cities between 1991 and 2006 to track and trace how gonorrhoea has become resistant to so many types of antibiotics, and to assess what that means for the spread of the infection. Ciprofloxacin-resistant gonococcal strains first spread to Hawaii and California during the late 1990s and became increasingly prevalent during the 2000s. By 2007, ciprofloxacin and other antibiotics of the fluoroquinolone family were no longer recommended by the CDC for treatment of the infection—they simply didn't work any more. That meant there were only two remaining treatment options.
At the moment, the CDC guidelines for gonorrhoea recommend dual therapy with an injection of one antibiotic (a cephalosporin called ceftriaxone) and an oral dose of another (either azithromycin or doxycyclin). That's the only remaining first-line treatment. "However, the possible emergence and spread of cephalosporin resistance could eventually threaten the effectiveness of this regimen and pose a major public health challenge," they wrote. We're running out of options.
Researchers also found that increased resistance to an antibiotic leads to an increase in the number of gonorrhoea cases; they suggested that if 10 percent of gonorrhoea samples are resistant to the treatment, there will be a 7 percent increase in gonorrhoea cases. It makes sense, of course; if you're infected with a resistant strain, it will take more time to treat it, and that'll give you plenty of time to share it around with others. Alternatively, they posited that the mutation that made the bacteria antibiotic-resistant could also have made it better at spreading.
Gonorrhoea is already adapting, as Sarah Kidd, a medical epidemiologist at the CDC, told the Verge. According to Kidd, the CDC has had to change its remaining recommended treatment twice, by increasing its dosage and the drug combination used. Although no resistant cases have been identified in the US yet, several cases of the cephalosporin-resistant infection have been reported in Japan, France, and Spain.
Of course, the problem of antibiotic resistance isn't limited to gonorrhoea. As we exhaust our supplies of antibiotics as more bacterial strains become resistant to them, we will find it increasingly difficult to treat many infections: infected cuts, throat bugs, chest infections, skin conditions, and everything else we throw antibiotics at.
For now, take this as a reminder to play safe.