Enterotoxigenic Potential ofStaphylococcus intermedius

Abstract

Staphylococcal food poisoning (SFP) caused by enterotoxigenic staphylococci is one of the main food-borne diseases. In contrast toStaphylococcus aureus, a systematic screening for the enterotoxins has not yet been performed on the genomic level for the coagulase-positive speciesS.intermedius. Therefore, the enterotoxigenic potential of 281 different veterinary (canine,n= 247; equine,n= 23; feline,n= 9; other,n= 2) and 11 human isolates ofS.intermediuswas tested by using a multiplex PCR DNA-enzyme immunoassay system targeting the staphylococcal enterotoxin genessea,seb,sec,sed, andsee. Molecular results were compared by in vitro testing of enterotoxin production by two immunoassays. A total of 33 (11.3%)S.intermediusisolates, including 31 (12.6%) canine isolates, 1 equine isolate, and 1 human isolate, tested positive for thesecgene. In vitro production of the respective enterotoxins was detected in 30 (90.9%) of these isolates by using immunological tests. In contrast, none of 65 veterinary specimen-derived isolates additionally tested and comprising 13 (sub)species of coagulase-negative staphylococci were found to be enterotoxigenic. This study shows on both molecular and immunological levels that a substantial number ofS.intermediusisolates harbor the potential for enterotoxin production. Since evidence for noninvasive zoonotic transmission ofS.intermediusfrom animal hosts to humans has been documented, an enterotoxigenic role of this microorganism in SFP via contamination of food products may be assumed.

Part of CIRS Nexus · Curated by Lauren Lowenstein, The Biotoxin Lady