Purpose: The purpose of this study was to compare antimicrobial susceptibility profile among microbial flora isolated from foodhandlers’ hands and food preparation surfaces in 15 hospice kitchens around Central South Africa.
Methods: Minimum inhibitory concentration was determined on 100 strains using the agar dilution method according to the CLSI. Antibiotic powders obtained from Sigma were as follows: chloramphenicol, gentamicin, oxacillin, cefoxitin, nalidixic acid and tetracycline. The inoculum was prepared by direct suspension of colonies from overnight cultures (Mueller-Hinton agar), into 9ml saline solution to achieve a suspension equivalent to 0.5 McFarland standards. The plates containing doubling antibiotic concentrations (0.25–256 mg.ml-1) were inoculated with 1 × 105CFU/spot using a multipoint inoculator. MICs were read after 48h of incubation at 35ºC.
Results: All the Acinetobacter baumanii strains were resistant to cefoxitin (0% susceptible). About 60% of Staphylococcus aureus isolates isolated from food handlers’ hands were resistant to tetracycline (MIC range, 32-128 mg.ml-1). Enterococcus faecalis strains were also resistant (90%) to gentamicin (MIC range, 0.25->128 mg.ml-1).
Significance: The implication of data is that microorganisms from the hospice environment are becoming multidrug resistant compared to the previous years and this is of great concern to this vulnerable health care setting