Abstract
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Abstract; Background:; Staphylococcus aureus carriage is a known risk factor for staphylococcal disease. However, the carriage rates vary by country, demographic group and profession. This study aimed to determine the S. aureus carriage rate in children in Eastern Uganda, and track Staphylococcus strains that can cause infection in Uganda.; Methods:; Nasopharyngeal samples from 742 healthy children under 5 years residing in the Iganga/Mayuge Health & Demographic Surveillance Site in Eastern Uganda were processed for isolation of S. aureus. Antibiotic resistance based on minimum inhibitory concentrations (MICs) was determined by the BD Phoenix™ automated identification & susceptibility testing system. Genotyping was performed by spa typing.; Results:; The processed samples yielded 144 S. aureus isolates (one per child) therefore, the S. aureus carriage rate in children was 19.4% (144/742). Thirty one percent (45/144) of the isolates were methicillin resistant (MRSA) yielding a carriage rate of 6.1% (45/742). All MRSA isolates were susceptible to vancomycin, linezolid and clindamycin however, compared to methicillin susceptible S. aureus (MSSA) (68.8%, 99/144), MRSA isolates were more resistant to non-beta-lactam antimicrobials –tetracycline (91.1%, 41/45), trimethoprim/sulfamethoxazole (73.3%, 33/45), erythromycin (75.6%, 34/45), chloramphenicol (60%, 27/45), gentamicin (55.6%, 25/45) and ciprofloxacin (35.6%, 16/45). Furthermore, one MRSA isolate was mupirocin resistant and 42 (93.3%, 42/45) were multidrug resistant (MDR); three (3%, 3/99) MSSA isolates were mupirocin and clindamycin resistant, while 61 (61.6%, 61/99) were MDR. All MSSA/MRSA isolates were susceptible to rifampicin, vancomycin and linezolid but only three MSSA were pan-susceptible to antibiotics. Seven spa types were detected in MRSA, of which t037 & t064 were predominant and associated with SCCmec types I & IV, respectively. Fourteen spa types were detected in MSSA, of which t645 & t4353 were predominant.; Conclusions:; S. aureus (MSSA/MRSA) carriage rate in children in Eastern Uganda is high and comparable to rates for hospitalized patients in Kampala city. The detection of mupirocin resistance is worrying as it could rapidly increase if mupirocin is administered in a low-income setting. S. aureus strains of spa types t064, t037 (MRSA) and t645, t4353 (MSSA) are prevalent and could be responsible for majority of staphylococcal infections in Uganda.