Joakim Larsson BIO
Joakim Larsson is a Professor in Environmental Pharmacology at the Department of Infectious Diseases, University of Gothenburg, Sweden, and the director for the multidisciplinary Centre for Antibiotic Resistance Research (CARe) at University of Gothenburg, involving +100 researchers from six faculties. He is also on the scientific advisory board for the JPIAMR. The focus of his own research group is on the environmental dimensions of antibiotic resistance and he has (co)-authored more than 190 papers to date (listed as highly cited researchers by Clarivate since 2018). His earlier work on environmental pollution from drug manufacturing and his research on selective concentrations of antibiotics has contributed to various management initiatives across the world. Larsson is the chair of the upcoming EDAR6 conference.
The role of the environment in antibiotic resistance development has become more and more recognised among both the scientific community and stakeholders. Thousands of scientific papers describe widespread occurrence of antibiotic residues, resistant bacteria and resistance genes in various environments. Accordingly, policy makers call for actions to reduce exposures. Still, perspectives on exactly how or to what extent observations of antibiotics, resistant bacteria or resistance genes in the environment indeed reflect an impact on or a risk for human and animal health are often lacking.
The environment plays at least three conceptually different roles in antibiotic resistance. The first is as an arena for the evolution of resistance in pathogens. Indeed, the most striking feature of the environmental microbiome is its immense diversity, providing an almost endless palette of genetic mechanisms that potentially could be acquired and used by pathogens to counteract the effect of antibiotics. The second role of the environment is not related to changes in DNA but merely the transmission of resistant pathogens that are already circulating widely among people and/or domestic animals. These two, evolution and transmission, could be seen as “active roles” where processes in the environment will affect the risks for the development and spread of resistant infections. More recently, it has been acknowledged that the abundance and pattern of resistance in environmental microbiota, particularly sewage, could serves as a passive reflection of the resistance situation in the local human, or animal, populations. A fourth role, not covered in this talk, is as a source for novel antibiotic molecules and thus drug development.
Our understanding of, and the evidence base for the three first roles, is fragmented. Here, I will attempt to structure the different risk scenarios, and discuss the evidence for each of the steps involved, based on both field- and experimental observations. I will also discuss methods for studying antibiotic resistance in the environment, particularly in terms of how likely surrogate endpoints are to reflect outcomes of concern (validity). Finally, I will discuss some possibly measures to reduce risks, and describe some recent mitigations.