Abstract:
Background: The colonization of nasal nares of health care workers with Methicillin-resistant 
Staphylococcus aureus are the major source of infection. Accurate and early determination of 
Methicillin resistance is of key importance in the prognosis of infections caused by S. aureus. 
However, there is limited study has been conducted regarding the colonization of health care 
workers with Methicillin-resistant S. aureus in Harar, Eastern Ethiopia.
Objective: The main objective of this study was to determine the prevalence of nasal carriage of 
Methicillin-Resistant Sthaphylococcus aureus associated factors and Antimicrobial susceptibility 
patterns among health care workers of public hospitals in Harar, Eastern Ethiopia from May 15 
to July 30 2021.
Method: A hospital-based cross-sectional study was conducted in 295 study participants. Nasal 
samples were collected by sterile cotton swabs. Then each nasal was inoculated onto Mannitol 
salt agar and blood agar plates and incubated aerobically at 37oC for 24h. Isolated pure colonies 
were identified using standard microbiological methods. Modified Kirby-Bauer disk diffusion 
technique was used for antibiotic susceptibility pattern of Staphylococuss aureus using different 
antibiotics. Cefoxitin-resistant strains were confirmed as Methicillin-resistant S. aureus. Data 
were entered into EPI-Info version-7 and then transferred to SPSS version-20 for analysis. 
Factors associated with nasal carriage of Methicillin-Resistant Staphylococuss aureus were 
determined by using chi-square analysis. A p-value of less than 0.05 was considered statistically 
significant.
Result: The prevalence of Staphylococuss aureus and Methicillin-resistant Staphylococcus 
aureus in this study was 15.6% (95% CI: 11.7%, 20.3%) and 11.2% (95% CI: 7.8%, 15.4%) 
respectively. age (P<0.001), work experience (p<0.001), working unit (p<0.02), antibiotic use 
within 3 months (p<0.001), hand washing habit (p<0.01), hand rub use (p<0.001), living with 
smokers (p<0.001), living with pets (p<0.001) and having chronic diseases (p<0.001) were found 
significantly associated with Methicillin-resistant Staphylococcus aureus nasal carriage. 
Conclusions: The prevalence of Staphylococuss aureus and Methicillin-resistant Staphylococcus 
aureus are highest in our study, urging a better diagnostic, screening and antimicrobial 
susceptibility testing to combat Staphylococuss aureus transmission and the emergence of 
antimicrobial resistance infection in our clinical setting.