Antibiotic and Disinfectant Susceptibility Patterns of Airborne Bacteria Isolated from Restaurants in Nigeria.

Abstract

Antibiotics resistant airborne bacteria in restaurants have considerable effect on not only the life of food handlers, but also the quality and stability of food products. This study was carried out with the objectives of identifying the type of airborne bacteria associated with the restaurants and their susceptibility patterns to commonly used antibiotics and disinfectants. Using depositional sampling technique, air samples were collected from restaurant kitchens and dining rooms and cultured aerobically. Bacterial isolates were identified based on biochemical tests and selective/differential plating. Among the ten (10) bacterial species isolated and identified, Staphylococcus aureus 7 (19%), Micrococcus spp. 6 (17%), Staphylococcus spp. 5 (14%), and Bacillus subtilis 4 (11%) were predominant. A total of fourteen antibiotics were used in this study: Amoxicillin + clavulanic acid (AU) (25), gentamycin (CN) (10μg), pefloxacin (PEF) (10μg), ofloxacin (OFX) (30μg), streptomycin (S) (30μg), chloramphenicol (CH) (30μg), co-trimoxazole. (SXT) (30μg), fluoroquinolone (SP) (10μg), ciprofloxacin (CPX) ((10μg)), amoxicillin (AM) (30μg), ampiclox (APX) (30μg), erythromycin (E) (19μg), ceftriaxone (CTR) (30μg) and cefuroxime (Z) (20μg). Antimicrobial susceptibility test results revealed that S. aureus had susceptibility of 6 (85.7%) each to ciprofloxacin and gentamycin but resistant to amoxicillin, ampiclox and cefuroxime while Pseudomonas aeruginosa had susceptibility of 3 (100%) each to amoxicillin + clavulanic acid and gentamycin but resistant to fluoroquinolone and co-trimoxazole. Susceptibility to Jik and Dettol was appreciable; they were bacteriostatic at 25-100% concentrations (Minimum Inhibition Concentrations (MIC) and bactericidal (Minimum Bactericidal Concentrations (MBC) at mostly 100% concentration. ‘Mama Lemon’ was bacteriostatic to only two isolates at 50 and 100% concentrations but not bactericidal. Enterobacter sp. was susceptible to neither the antibiotics nor the disinfectants. All the three disinfectants showed no efficacy at concentrations lower than 25%. The presence of potentially pathogenic bacteria which are not susceptible to antibiotics and disinfectants in the air of restaurants constitutes a serious health hazard not only to the restaurant workers and their customers, but also the general public.