©Alin Gavriliuc via Unsplash
A 5,000-year-old bacteria resistant to antibiotics has emerged from ice in Romania. It's not the plot of a dystopian series, but a real scientific discovery that weaves together climate crisis, global health and biotechnologies. It's also a discovery that forces us to ask an uncomfortable question: what's making a return from the melting ice?
In the heart of the Western Carpathians, in the Apuseni Mountains, lies the Scărișoara Cave, one of the largest ice caves in Europe. Here, ice is not just landscape: it's memory. Layer after layer, it preserves traces of thousands of years of environmental history.
From a 25-meter-long ice core - a true natural archive that spans some 13,000 years - an international team led by the Institute of Biology in Bucharest has isolated a strain of bacteria trapped under a layer about 5,000 years old, around 3,000 B.C.
Its name: Psychrobacter SC65A.3. A technical name, sure. But the story behind it is anything but cool and distant. It was transferred to the laboratory in sterile conditions, and there, the microorganism was tested against 28 preparations from ten different classes of antibiotics. It was found to be resistant to ten modern antibiotics, including metronidazole, vancomycin, trimethoprim, clindamycin, rifampicin and ciprofloxacin. These are agents we use against lung, urinary tract and systemic infections and even tuberculosis.
Even more significant is what the genetic analysis revealed: more than 100 genes linked to antimicrobial resistance. The study, published in Frontiers in Microbiology, shows that antibiotic resistance is not a 'bug' of the modern era. It's a natural phenomenon, deeply embedded in microbial evolution.
Even before humans produced antibiotics in the laboratory, bacteria and fungi competed among themselves for survival using chemical molecules. In extreme environments such as ancient ice, this battle selected microorganisms with a surprising genetic arsenal.
A real risk or a new resource?
This is where the climate crisis comes in. Global warming is accelerating the melting of glaciers and permafrost. And as the ice melts, everything that was trapped in it comes back into circulation. Scientists warn: if resistance genes such as those in Psychrobacter SC65A.3 were to transfer to modern pathogenic bacteria, the already severe antibiotic resistance crisis could worsen.
According to the World Health Organization, antibiotic-resistant infections are among the greatest global health threats. In the coming decades, they could cause up to 10 million deaths annually. These figures are thought-provoking. Yet the story is not just ominous. The same strain from the Romanian cave was also shown to be able to inhibit the growth of other resistant bacteria in the laboratory. In other words, it could produce new antimicrobial molecules, useful for developing next-generation drugs.
In a sense, nature shows us both sides of the coin. On the one hand, the risk associated with the release of ancient microorganisms on a planet that is warming far too fast. On the other, a potential goldmine of biotechnological solutions, right in that same ice.
The 5,000-year-old bacteria resistant to antibiotics is not just a scientific curiosity. It is a signal. It reminds us that the climate crisis is not just about temperatures and retreating glaciers. It's about invisible equilibria, about microscopic worlds reconnecting with our own. Perhaps the real question is not whether we should be afraid, but whether we are willing to listen to what the ice, as it melts, is trying to tell us.
(Frontiers in Microbiology via GreenMe.it 2026/Managing Editor: Julie Morgan - The Press Junction/Picture: ©Jonas Leupe via Unsplash)