Figure 2

Inferred genetic relationships between S. suis isolates recovered from diseased pigs in seven European countries based on the seven genes used in the multilocus sequence typing scheme (MLST). A maximum likelihood phylogenetic tree was constructed by concatenating the sequences of genes (aroA, cpn60, dpr, gki, mutS, recA, and thrA) used in the S. suis MLST scheme. Each sequence type (ST) is plotted with the number of isolates (N) indicated beside each ST. Colored circles represent the countries of origin for the isolates—Belgium, France, Germany, Hungary, the Netherlands, Spain, and the United Kingdom, as per the key, providing a visual representation of the geographic distribution of genetic variants. Notably, ST1 and ST16 isolates were the most prevalent, but we identified a total of 34 STs, including 16 novel STs.