Itziar Alkorta: The Race Against ‘Superbacteria’: The One Health Approach to the Antibiotics Crisis
Around 30,000 deaths a year due to infections caused by antibiotic-resistant bacteria are currently recorded in Europe. If action is not taken, the world is facing a global crisis that could lead to 40 million deaths a year by the middle of the century. As Itziar Alkorta Calvo, Professor of Biochemistry and Molecular Biology at the University of the Basque Country (EHU), explained at a Donostia Sustainability Forum event, the key to addressing this crisis lies in the ‘One Health’ concept. This approach recognises that human, animal and environmental health are closely interconnected. ‘We cannot affect one type of health without affecting the others’, Itziar Alkorta stressed.
The microbiome is at the centre of this connection. It is defined not only as the set of microorganisms (microbiota) that live in a body, but also their ‘theatre of activity’, which includes molecules, metabolic flows and the surrounding environment. The microbiome acts as the microscopic nexus between those niches. As she explained, the use of antibiotics in livestock, for example, generates resistant bacteria that reach our dishes through the food chain or the environment through wastewater discharges.
Resistant bacteria
One of the most fascinating discoveries in microbiology is bacteria’s ability to exchange information by means of bacterial conjugation, a type of horizontal genetic transfer that allows the antimicrobial resistance to spread. The bacteria use plasmid DNA molecules to share resistance genes promiscuously, even between different species. That creates a communal ‘supergenome’, where any bacteria can borrow tools not only to survive antibiotics, but also heavy metals or contaminants.
‘The supergenome is as if an owners’ association had a room where any of them could leave stuff there that they don’t need at that time, but which may be important at one point’, explained the expert.
Accordingly, Itziar Alkorta warned about the role of microplastics and nanoplastics in nature. They act as ‘hot points’ where bacteria form biofilms, are protected from external attacks and are exposed to a cocktail of contaminants that trigger the spread of resistance. ‘Micro- and nanoplastics accumulate contaminants and bacteria, and that is the perfect storm for those bacteria to become resistant’, she added.
Anti-resistance strategies
Research is now focused on new strategies, given the difficulty and high costs of developing new antibiotics - a process with a low return for pharmaceutical companies compared to drugs for chronic diseases. Itziar Alkorta’s group uses, for example, nanotechnology techniques to encapsulate existing antibiotics, which allows them to be more effective at lower doses and gives them a ‘second therapeutic life’. Furthermore, they are designing molecules aimed at disrupting communication between bacteria. And they have already identified between three and four molecules that, in laboratory tests, have managed to stop the bacteria from conjugating or that they do so far less effectively.
‘There is not a single solution; there has to be an arsenal of options to use where and when’, Itziar Alkorta pointed out. She went on to stress the importance of researching the natural reservoirs of resistant bacteria in the environment, in places such as hospitals or water treatment plants. The aim is to create standard watch systems that allow multiple assays to be conducted simultaneously to monitor environmental health at a global level.
Proper hygiene and treatments
Beyond the laboratory, the expert explained that ‘there is no better treatment than prevention’. Ensuring basic hygiene habits, avoiding the unnecessary use of antibiotics and strictly following the treatment regime are fundamental to limit the spread of resistant bacteria. Furthermore, she recalled that a single course of antibiotics can alter the intestinal microbiota for years; she compared the effect to that of burnt upland that takes decades for its original species to return.
