Characterization of hospital and community strains of Staphylococcus aureus for resistance to antimicrobial drugs, metallic ions, disinfectants, thermal injury and solar radiation.
One hundred and sixty strains of Staphylococcus aureus isolated from various clinical specimens were classified into groups: hospital staphylococci (HS) or community staphylococci (CS), based on the clinico-ecological circumstances of isolation. Fifty strains from both groups were tested for the minimum inhibitory concentration (MIC) of penicillin G, streptomycin, tetracycline, chloramphenicol, mercuric chloride, disodium hydrogen arsenate, silver nitrate and sodium bisulphite. Four representative strains from each group were further studied for resistance to "in-use" dilutions of 4 disinfectants (Dettol, Izal, Savlon and Chlohexidine), heat stress and the effect of solar radiation in sand cultures. All HS and 31.8% of CS were resistant to penicillin and ampicillin and produced penicillinase. HS had higher MICs of antibiotics and metallic ions and longer bactericidal times with disinfectants than CS. Resistance to thermal stress varied within each group but survival in sand cultures under solar radiation appeared to be influenced by multiple factors to which community staphylococci were probably better adapted.
D004202:Disinfectants / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D006358:Hot Temperature; D006801:Humans; D007297:Inpatients; D008670:Metals / Q000494:pharmacology*; D010045:Outpatients; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000528:radiation effects; D013447:Sulfites / Q000494:pharmacology*; D013472:Sunlight
D004202:Disinfectants; D008670:Metals; D013447:Sulfites