Mycoplasma genitalium – what we know about the newest STI on the block.
Sean*, a gay guy in Melbourne, had been getting his standard STI testing done at least twice a year. Then, in September 2016, a guy he’d been sleeping with called to tell him that he’d tested positive for an STI. Sean made an appointment with his doctor and also tested positive. But this was an STI neither Sean nor his buddy had ever heard of: Mycoplasma genitalium. “I didn’t know it was something I needed to test for, and neither did my doctor,” he says. “I didn’t have any symptoms, so it was a bit of a shock.”
What’s that you say? A new STI to worry about?
It’s the unhappy truth. In recent years, alongside water on Mars and mini dancing peacock spiders which are fabulous, science has also identified some new organisms that live in your private parts.
“MGen can only be detected with genetic testing, which is what most STI tests use now,”
If you’ve never heard of Mycoplasma genitalium — or MGen — you’re not alone. As far as STIs go, MGen doesn’t yet have the notoriety of pests like chlamydia, gonorrhea and syphilis. But it’s getting a lot of attention for a few reasons, not least of which is the fact that it seems to be developing resistance to antibiotics at a cracking pace.
But there’s no need to panic. We’ve got everything you need to know about the newest STI on the block, and how to protect yourself.
What is MGen?
M. genitalium is a bacterium, like the organisms which cause chlamydia, syphilis and gonorrhea. It affects men and women, and can infect the urethra, the anus or the cervix. It’s passed on through condomless anal or vaginal sex.
What are the symptoms?
MGen can have similar symptoms to chlamydia. If you have a urethral infection, you may have some pain when passing urine. You may also have some discharge from the penis.
Importantly, just like Sean, some men will have no symptoms at all, particularly if they have an anal infection.
Why are we only just hearing about it?
We spoke to Colin Denver, CEO of SpeeDx, an Australian company leading the charge in testing and diagnosing MGen, to find out how MGen has managed to fly under the radar for so long.
“MGen isn’t technically ‘new’ at all,” says Denver. “It was originally identified in the 1980s, but due to the limitations of technology at the time, the results weren’t able to be repeated reliably. It’s also very hard to grow in a lab with traditional processes. Scientific interest faded, and it wasn’t until the advent of genetic testing that we really saw it studied properly.”
“MGen is actually a far more common cause of urethritis than gonorrhea.”
The re-emergence of MGen as a subject of interest is important. The US Centre for Disease Control (CDC) now attributes approximately 15–20 per cent of non-gonococcal urethritis (NGU) cases, 20–25 per cent of non-chlamydial NGU cases, and approximately 30 per cent of persistent or recurrent urethritis to MGen infection.
“The assumption has historically been that urethritis was caused either by chlamydia or gonorrhea, and if they weren’t detected then the infection was just classified as ‘non-specified’,” explains Denver. “If we go back and test with what we know now, we find that the most common cause of urethritis after chlamydia was MGen, which is now approaching the infection rates of chlamydia. MGen is actually a far more common cause of urethritis than gonorrhea.”
How do they test for MGen?
For guys, MGen tests can be taken from a urine sample, a urethral swab or an anal swab.
“MGen can only be detected with genetic testing, which is what most STI tests use now,” says Denver.
“Sean tested positive to antibiotic-resistant MGen, and he was successfully treated with second-line antibiotics.”
Is it part of normal STI screening? Do I need to request it specifically?
Sean’s story is hopefully becoming a thing of the past. “Guidelines are now changing to recommend that anyone presenting with urethritis or cervicitis receive a test for MGen,” says Denver. “…always double check if you want to be sure – any doctor can do it.”
Is antibiotic-resistant MGen still treatable?
Yes. Sean tested positive to antibiotic-resistant MGen, and he was successfully treated with second-line antibiotics. “I was on antibiotics for two weeks. Then I retested and got the all-clear,” he says. “It was quite worrying having an STI I’d never heard of, but treatment was fairly simple.”
How do I protect myself from getting MGen?
Look no further than your most faithful friends — condoms and lube. Just as with other bacterial STIs, condoms are the best protection against MGen when you’re having anal sex.
*name changed for protection of privacy