Drug resistance and plasmid profiles in Staphylococcus epidermidis in 1964 and 1986.

An examination has been made of drug resistance and plasmid content of Staphylococcus epidermidis isolated from hospital patients in 1964 and 1986. Drug resistance was much more prevalent in isolates from 1986 than in isolates from 1964. Plasmids were demonstrated in 50 of 52 strains from 1964 and in 102 of 111 strains from 1986. The majority of both drug-sensitive and drug-resistant strains harboured more than one plasmid. Of five plasmids obtained from a multiply-drug-resistant S. epidermidis, four were shown to mediate drug resistance.