Pathogenicity of coagulase-negative Staphylococci for turkey embryos

Chemical alterations in the human environment caused by popular antibiotherapy are a reason for biochemical alterations in bacteria. It is probably the key to understanding the acquired pathogenicity of coagulase-negative Staphylococci: Staphylococcus epidemidis and Staphylococcus saprophyticus, which were known as non-virulent bacteria. A set of thirty four coagulase-negative strains (S. epidermidis, S. species and S. saprophyticus) and six standard coagulase-positive S. aureus strains isolated from ill and healthy individuals were tested. Eight-day old turkey embryos were vaccinated with the bacteria. The results of the test (LD(50) for 24 and 48 hours) showed that there was no relationship between the virulence of these bacteria for turkey embryos and the production of coagulase (or other metabolites typical for S. aureus). It is interesting that coagulase-negative Staphylococci were the strains most virulent for turkey embryos. Besides, there is no connection between the noted characteristics of the assessed bacteria and their taxonomic position. Many infections dangerous for people can be caused by uncontrolled chemical interference into the human bacterial environment.