A drug resistant sexually transmitted infection (STI) detected in Australia’s Northern Territory is worrying health authorities and potentially posing a serious threat to remote Aboriginal communities.
In a first for the region, the case of extensively drug resistant (XDR) gonorrhoea showed resistance to treatment by Ceftriaxone and Azithromycin, antibiotics routinely used to treat gonococcal infections.
In early June, the NT Centre for Disease Control issued a public health alert, stating the infection had been acquired locally (not overseas), and that a source remains unknown.
Widely detected globally, gonorrhoea and other STIs are problematic in regional and remote Australia where a laboratory capable of accurately diagnosing exactly which infection is present may be hundreds of kilometres away in the nearest big town or city.
But testing techniques operable by remote primary health staff may help, says new research.
A global issue
According to UNSW’s Kirby Institute, gonorrhoea is a common STI caused by the bacteria Neisseria gonorrhoeae, can affect both sexes, and is spread via vaginal, oral, and anal sex.
Gonorrhoea most commonly infects the urethra and cervix but may also infect the anus and throat. Such infections may cause different symptoms in women and men, with women quite often feeling none.
While such infections are largely curable (for now, at least), a 2024 review led by Kirby Institute professor Louise Causer and published in The Lancet Regional Health -Western Pacific notes serious complications can arise nonetheless, including pelvic inflammatory disease, infertility and adverse outcomes for pregnancies among others, as well as spreading the infection to other sexual partners.
The effect is global, with figures from the World Health Organisation for 2020 estimating “374 million new infections with one of four STIs: chlamydia (Chlamydia trachomatis), gonorrhoea (Neisseria gonorrhoeae), syphilis (Treponema pallidum) and trichomoniasis (Trichomonas vaginalis).”
Low- and middle-income countries are most affected, writes Prof. Causer, though sub-groups in high income countries also experience high rates of STIs. These groups include men who have sex with men, those subject to gender-based violence, the homeless and disabled, and First Nations peoples.
Of 40,029 gonorrhoea notifications recorded in Australia during 2023 more than two‑thirds were from males, with the overall infection rate having risen by 127% since 2014 (to 153.9 cases per 100,000).
Among Aboriginal and Torres Strait Islander peoples, the rate was more than four times the non‑Indigenous figure. In fact, on Australian regional and remote Aboriginal communities, Prof. Causer notes that at any given time “just under half of all young people aged 16–19 years have an STI”. Other UNSW figures suggest up to half of pregnant women in Papua New Guinea may have STIs with no symptoms, potentially yielding miscarriage, pre-term birth and low birth weight.
When STIs resist treatment
Head of the NT Government’s Sexual Health Unit at the Centre for Disease Control (CDC) in Darwin Dr Manoji Gunathilake says health effects can be compounded when a strain of an STI proves drug-resistant.
“Antibiotic resistance occurs when the antibodies we are giving to a patient are not effective or (only) partially effective in some situations,” she says. “Also, the microorganism can change its structure to become resistant to certain medicines.
“In the case of gonorrhoea, it has, over the years, acquired the ability to become resistant to several antibiotics we have used to treat (it).”
In the past, penicillin was the go-to treatment.
“But several years ago, we had to stop using penicillin because gonorrhoea became resistant,” Dr Gunathilake says. “Previously in the NT we could give some remote patients the penicillin orally, but about 3 years ago penicillin resistance emerged in those localities, and we had to stop using it.”
Almost 700 notifications of gonococcal infection were reported in the NT to June 2025, with cases growing annually.
Now, case numbers for multi-drug resistant (MDR) and XDR gonorrhoea are rising globally, especially in Southeast Asia.
Dr Gunathilake says testing is conducted by PCR test, a type of nucleic acid amplification test (NAAT), which detects genetic material from a pathogen or abnormal cell sample.
“But to understand a person is having resistance to ceftriaxone or azithromyecin we need to test for culture, so we take a sample … and use the culture media to grow the organism then test the organism against antibiotics.”
The recent XDR patient was tested and initially treated, Dr Gunathilake says, a culture sample obtained, and the lab managed to grow the organism.
“Then we got a phone call from the lab that the organism was showing some degree of resistance.”
Dr Gunathilake says the cornerstone of treatment is now an antibiotic called ceftriaxone.
“Used alone or in combination with a medicine called Azithromycin, which is given orally … (but) “azithromycin cannot be given alone … it is not effective by itself.”
Ceftriaxone resistance started emerging in other countries several years ago, then in Australia and the UK, though case numbers were higher in Southeast Asia.
“For the NT, it is the first time we have seen this degree of ceftriaxone resistance,” Dr Gunathilake says. “Luckily the person responded to ceftriaxone; (they) became symptomless and remained negative when retested.”
Now NT Health is warning everyone: If you are sexually active, get your STI screens done.
With a lot of people travelling to SE Asia where there have been several cases of resistance, many Australian cases have acquired resistance from their travels, says Dr Gunathilake.
And it was fortunate the drug-resistant case came in for testing.
“And when (they) became symptomatic and were treated for gonorrhoea, they informed their partners.
“They asked them to go and get the treatment and believe those people actually went.”
The NT alert of 5 June directs doctors and nurses to take a travel history as part of any assessment of patients presenting for an STI screen.
“If they are sexually active, get their STI screens done; the current recommendation is for at least 2 screens a year in remote settings.
“For individuals at higher risk, they (should) get tested every three months.”
Testing in remote settings
An issue for Australian remote Aboriginal communities has been that all testing must happen at often poorly equipped remote health clinics, where many who may well be symptomless may not get tested.
A drug-resistant case in the Top End focuses attention on this broader issue, where limited access to laboratory testing can mean weeks to get critical results back from a distant testing laboratory.
And there are other issues.
“For our people in communities,” says Dr Gunathilake, “many tests were occurring, but we have to keep doing them and concentrate more on younger people, they are the challenge because they don’t usually come to the health service.
“And these STI’s (can) remain asymptomatic or mildly symptomatic and people don’t see any need to go and get treatment immediately.”
Extensive recent trials in Australia are showing promise from Molecular Point of Contact Testing (POCT), a medical test “conducted at or near the site of patient care.”
The attraction is the ability to diagnose infectious disease in locations with limited infrastructure, such as at health clinics on remote Aboriginal communities.
According to recent UNSW research this testing can enable patients to “be diagnosed and treated on the same day, avoiding the need for health services to track down patients who are often mobile and difficult to locate, days or weeks later.”
According to Prof. Causer, using the method for STIs was evaluated at almost 50 primary care clinics over a 7-year period, the study demonstrating that POCT was able to accurately test for chlamydia and gonorrhoea just as well as a laboratory.
Nonetheless, Dr Gunathilake remains worried about drug resistance “across the board.”
“Antibiotic resistance is becoming a serious global problem,” she says, “and I’m worried about that. But also, I’m hopeful that further effects of (drug) resistance will not happen, and we can keep giving these drugs for the next ten years or so.”