In Poland, the population of game animals, including wild boars, roe and deer, is constantly increasing. The tonsils of wild game animals are a place of large variety of microorganisms. The pathogenic bacteria present in them, such as E. coli, Y. enterocolitica and Salmonella sp. are the most common source of meat infection. The opportunistic bacteria R. aquatilis, P. fluorescens,
S. liquefaciens, S. fonticola and S. plymuthica also play an important role in public health. S. liquefaciens may be an opportunistic pathogen and in people causes sepsis and inflammation of the
cornea. The protease, nuclease, phospholipase A, flagella, elastase and toxins haemolysin and
proteolysin are responsible for its ability to cause disease symptoms. S. plymuthica, a rod commonly
found in the environment, produces a red dye. It is most often isolated from soil, water
and food. In humans, it causes infections of burn wounds, soft leg tissue as well as post-operative
wounds and bacteraemia. Typically, the environmental rod S. fonticola differs from other Serratia
sp. by the lack of extracellular enzymes. It causes wound infections and bacteraemia resulting
from urinary tract infections. Bacteria from the genus Serratia sp. show a natural resistance
to glycopeptides, rifampicin and erythromycin. The aquatic rod R. aquatilis in humans causes
opportunistic infections of the urinary tract, wounds, bacteraemia and endocarditis. It exhibits
natural resistance to antibiotics from the group of cephalosporins, penicillins and macrolides
and quinolones. It is conditioned by the presence of class 1 integrons and class A β-lactamases.
The virulence factors of R. aquatilis are also LPS and adhesin. P. fluorescens in humans is responsible
for bacteraemia. It also exhibits resistance to human serum thanks to outer membrane
proteins and has T3SS, which effectively infects the host.