Phage typing of coagulase-negative staphylococci isolated from various animals and humans in Japan.

Abstract

The phage typing of 226 strains of coagulase-negative staphylococci (CNS) isolated from 9 different animal species and humans was performed. CNS were identified using the simplified scheme of Kloos and Schleifer. With the human Staphylococcus epidermidis phage set of Pulverer, it was possible to type 109 (48.2%) of 226 strains of CNS at routine test dilution (RTD). Typabilities of the human, cattle, horse, swine, dog, rabbit, mouse, chicken, pigeon and quail strains were 60.0%, 54.5%, 50.0%, 40.7%, 100%, 53.8%, 100%, 37.7%, 0% and 100%, respectively. Although 33 different phage patterns were detected, 64 of the 109 typable strains were of phage pattern Ph5/Ph9/Ph10/Ph12/Ph13/U4/U14/U16/U20/U46. There was no significant relation between phage types and the origin of the strains. The phages Ph5, Ph9, Ph10, Ph12, Ph13, U4, U14, U16, U20 and U46 showed lytic activity on S. xylosus, S. simulans, S. epidermidis, S. cohnii, S. haemolyticus, S. capitis, S. hominis and S. warneri. The reacting ability of phages Ph6, Ph14, Ph15, Ph16 and U15 seemed to be limited to S. xylosus and S. epidermidis. Attempts were made to isolate phages for typing CNS strains from animals. Seven phages were isolated from lysogenic strains of CNS and their usefulness for the typing of CNS was evaluated. Of the 226 CNS strains examined, only 27 (11.9%) were typable at RTD. The temperate phages were of limited value in typing CNS strains of animal origin, although 9 of 117 strains untypable by Pulverer's phages were lysed by the present phages.