Genome analysis of Flavobacterium psychrophilum isolated from Swedish fish farms

High-throughput sequencing-based methodologies was applied to a collection of F. psychrophilum collected from fish farms in different regions of Sweden between 1988 and 2016 in order to better understand the population structure and phylogeography of the pathogen over time. It was shown that F. psychrophilum clones are not regionally biased and that new clones with a higher degree of antibiotic resistance have emerged nationwide during the study period. This supports previous theories of the importance of live fish and egg imports as a route of infection. Continuous monitoring of recovered isolates by high-throughput sequencing techniques in the future could facilitate tracing of clones within and between countries, as well as the detection of emergent virulent or antibiotic resistant clones.