One Planet, One Health, One Microbiome: A Holistic Approach to Antimicrobial Resistance

Antimicrobial Resistance has become one of the great threats to public health, food security and stability of the ecosystems. The inappropriate and excessive use of antibiotics in veterinary and human medicine, agriculture and other fields has triggered strong selective pressure that fosters the appearance and propagation of resistant bacteria. In 2022, the extent of the problem caused four international authorities – the World Health Organisation (WHO), the Food and Agriculture Organisation of the United Nations (FAO), the World Organisation for Animal Health (WOAH) and the UN Environment Programme (UNEP) – to join force in a four-party partnership to address this crisis from a One Health approach.

The One Health approach is a holistic view of health as it recognises how people, animals and the environment are interdependent. Its goal is to foster the partnership between fields such as medicine, veterinary medicine, ecology and public health to develop coordinated surveillance and monitoring systems, joint responses to health emergencies, and sustainable solutions based on scientific evidence. In the case of antimicrobial resistance, this approach is essential to understand the complexity of its origin and to control spread.

Even though resistance to antibiotics has traditionally been studied from the clinical perspective, the environment is now known to play a crucial role both in its appearance and in its transmission. An important part of the antibiotics used in human and veterinary medicine – and their transformation products – reach the soil, rivers and seas, where they act as an emerging pollutant and contribute to the selection of resistant bacteria in natural ecosystems.

Bacterial conjugation has a central place among the mechanisms that foster the spread of resistance. This process allows genetic material to be exchanged between bacteria, facilitating the transfer of resistance genes contained in conjugative plasmids. Consequently, a recipient bacterium does not only acquire resistance, but it also becomes a transmitter of those genes, which drives a rapid spread even between different species.

Our research group has spent over twenty-five years studying one of the key agents of this process: the coupling protein, present in all conjugative systems and fundamental for the transfer of conjugative plasmids to take place. In recent years, we have identified several molecules capable of inhibiting the activity of this protein, opening up new ways to curb the spread of resistance and offering a window of hope for this global challenge. Furthermore, we are working on developing new formulas for existing antibiotics, as we are aware that finding new antibacterial compounds will be difficult in the short-term. We therefore resort to nanotechnology, encapsulating antibiotics in nanoparticles in order to improve their effectiveness and extend their clinical usefulness given the increase in multi-resistant bacteria. Given the environment’s key role in this phenomenon, we are developing tools that allow the impact of the emerging pollutants on resistance appearance and spread to be anticipated.

Finally, and because global challenges require integrated responses, we are part of the Joint Research Laboratory on Environmental Antibiotic Resistance (https://www.jrl-environmental-antibiotic-resistance.eus/en/home-english/), an international network that combines different disciplines to progress in finding solutions for the problem of antibiotic resistance by means of research, training new scientists and raising awareness of this pressing problem.