Emerging ThreatsExtensively Drug-Resistant Neisseria Gonorrhoeae in Germany

A teenager in North Rhine-Westphalia walks into a clinic. There’s no recent travel, no unusual history — just a gonorrhoea infection that looks, on the surface, completely ordinary. The doctors run the standard treatment, but it doesn't work. What they find in the lab changes the picture entirely. That case, reported by Regina Selb and colleagues in 2025, is one of four confirmed gonorrhoea infections in Germany caused by bacteria that have essentially outrun our antibiotic options. Two of those four patients were in their late teens. Here's why that matters. Gonorrhoea is already one of the most common sexually transmitted infections among young people. For decades, we've stayed ahead of it with antibiotics — first penicillin, then ciprofloxacin, then azithromycin and cefixime. Each time the bacteria evolved resistance, we moved to the next drug. Now we're at the end of that list. Ceftriaxone is the last widely available antibiotic that reliably treats gonorrhoea. Selb and colleagues put it plainly: the emergence and local spread of extensively drug-resistant strains in Germany threaten the effectiveness of ceftriaxone for treating gonorrhoea. To understand what "extensively drug-resistant" actually means, think of it as a ladder of lost options. Multi-drug resistance, or MDR, means a strain can no longer be treated with several common antibiotics. Extensively drug-resistant, or XDR, means the bacteria have climbed higher: they're also resistant to the last-line drugs. In this report, Selb and colleagues used European Committee on Antimicrobial Susceptibility Testing, or EUCAST, version 15.0 breakpoints to interpret their results and defined XDR as resistance to both cefixime and ceftriaxone, a high azithromycin minimum inhibitory concentration — the lowest drug concentration that stops bacterial growth — above one milligram per litre, plus resistance to at least two other antibiotics such as ciprofloxacin or tetracycline. In the four German cases, the pattern was stark. All four isolates showed high-level azithromycin resistance — with measured concentrations above 256 milligrams per litre, far past the threshold for resistance. All four were resistant to cefixime. Two of the isolates, designated G25-563 and G25-K71, were also resistant to ceftriaxone, with minimum inhibitory concentrations of 0.19 milligrams per litre — enough to push them into the XDR category. The other two were classified as MDR, meaning serious but not quite at the final rung. Two genetic features explain how the bacteria got there. The strains carried a mosaic penA-60.001 allele — a rearranged version of a gene involved in the bacteria's cell wall construction that makes it harder for cephalosporin antibiotics like cefixime and ceftriaxone to bind and kill the cell. They also carried an A2045G mutation in all copies of their twenty-three S ribosomal RNA gene, which is what drives the high-level azithromycin resistance. In plain terms: two genetic changes, two drug classes neutralized, and the last antibiotic compromised or gone. Now to the cases themselves, because this is where the story gets personal. All four infections were identified in North Rhine-Westphalia, all in heterosexual men, ranging from late teens to mid-sixties. Critically, none reported recent travel abroad. That word "autochthonous" — locally acquired — is the key detail. Previous XDR gonorrhoea cases in Germany, one in 2023 and one in 2024, had been linked to travel to Southeast Asia. These four were not. The infections were picked up at home. The epidemiological link was contact with sex workers. Two patients explicitly reported sexual contact with a female sex worker in Germany. A third had heterosexual contact in Germany with sex-work exposure suspected by the treating physician. The fourth reported sex with a woman who was not his steady partner. The authors note these events seem restricted to heterosexual men with contact to sex work in a confined geographical area, but confined doesn't mean contained. One case appeared four months after the first in the cluster, suggesting the strain had been circulating quietly. Three patients were successfully treated with two grams of ceftriaxone — one as a single intravenous dose combined with oral azithromycin, one as a three-day intravenous course, and one as an intramuscular single dose — and tests of cure at four weeks were successful for reported cases. The fourth patient didn't return for his planned intravenous treatment and was lost to follow-up. The treatment successes are genuinely reassuring, but the paper cautions that success can depend on infection site — most documented failures with resistant gonorrhoea have involved throat infections, where drug penetration is lower. So how did scientists piece together where this strain came from? That's where the genomic detective work comes in. Selb and colleagues extracted DNA from the isolates, performed whole-genome sequencing, and ran the data through an in-house assembly pipeline. They then used a platform called Pathogenwatch to type the bacteria and build a phylogenetic tree — essentially a DNA-based family tree of the strains — comparing the German isolates against nine European XDR strains and previously reported travel-associated sequences. The results were striking. Three German isolates — G25-563, G25-K71, and G25-1113 — all belonged to the same molecular type: multilocus sequence type ST18091. G25-563 and G25-K71 differed from each other by just one single nucleotide polymorphism, a single-letter change in the bacterial genome. G25-1113 differed from those two by only two or three single nucleotide polymorphisms. In bacterial genomics, that level of similarity means these strains are extremely closely related — near-identical copies of the same lineage. On the phylogenetic tree, the three German isolates clustered together, separate from other European XDR strains. Their closest relative was a strain called H24-496, reported in the United Kingdom in 2024 and linked to travel to Cambodia. The lineage had moved from Cambodia to the United Kingdom, then from the United Kingdom to Germany, and now Germany to Germany. This is what autochthonous transmission actually looks like at the molecular level. It's not random emergence — it's a traceable chain. And the chain was only visible because Germany has infrastructure in place to see it. That infrastructure is the Go-Surv-AMR programme — Germany's national gonorrhoea resistance surveillance system, which pairs mandatory clinical notification to the Robert Koch Institute under the German Infection Protection Act with voluntary submission of bacterial isolates for resistance testing and whole-genome sequencing. Without it, these four cases might have looked like unrelated clinical failures rather than a coherent local outbreak. The raw sequencing data from this investigation are publicly available at the European Nucleotide Archive under accession PRJEB97528, contributing to the international picture. So what does all of this mean for a normal teenager and their future? The first thing to say is that ceftriaxone is not gone yet. It still worked in three of these four cases, and Selb and colleagues aren't declaring a treatment collapse. But the margin is narrowing. Two of four locally acquired cases carried strains resistant to every standard antibiotic we have for gonorrhoea. If that proportion grows — if XDR strains spread further into the general population — the treatment options for a young person with a routine gonorrhoea diagnosis start to look very different. The paper is explicit about which populations are most at risk and what needs to change. Selb and colleagues call for easily accessible STI testing and treatment for sex workers and their clients, men who have sex with men, and young people. They recommend susceptibility testing when resistance is suspected, individualized treatment decisions for confirmed XDR cases, and tests of cure to verify the infection has cleared. The local authorities in North Rhine-Westphalia already offer anonymous, free STI testing and treatment for sex workers — that kind of access is precisely the model the authors are advocating. The lesson for an adolescent listener isn't to panic, but to update. Resistance isn't something that only happens to travelers or to people with unusual exposures. These four cases happened locally, to people who stayed home. Know the symptoms — unusual discharge, burning, sometimes nothing at all. Get tested. And if you're told you have gonorrhoea, ask whether susceptibility testing and a test of cure are part of the plan. Those questions aren't excessive. Right now, they're exactly the right ones to ask. The surveillance system caught this cluster. That's the genuinely hopeful part of this story. But it only works if isolates keep being submitted, sequenced, and compared internationally. The early warning system is running. The question is whether we act on what it's telling us. This lecture was created by ennepō. Go to https://ennepo.ai to Discover, Create and Follow the latest research in your field. Read when you can. Listen when you want to.