Prevalence of Methicillin Resistant Staphylococcus aureus Nasal Carriage and Its Antibiogram in Healthcare Workers from South of Jordan

Background: Healthcare workers (HCWs) can act as asymptomatic carrier in transmitting Methicillin Resistant Staphylococcus aureus (MRSA). Availability of epidemiological and antibiotic susceptibility data is necessary to limit the spread of HCWs-associated MRSA infections, and to help physicians in choosing the appropriate empirical antibiotic for management of such infections. Objective: to assess nasal carriage and antibiogram of MRSA in healthcare workers from Southern Jordan. Methods: a total of 276 nasal swabs were randomly collected from the HCWs. MRSA was identified by culture, biochemical and molecular methods. Antibiotic susceptibility was determined by the disc diffusion method. Results: The HCWs-MRSA nasal carriage was 8.7%. There was significant difference for nasal carriage of MRSA by nurse occupation (p value = 0.007), education level of less than a university degree (p value = 0.039) and years of HCW experience (p value = 0.023). No significant difference by age, sex, antibiotic exposure or smoking. Antibiotic resistance to Trimethoprim-Sulfamethoxazole and Tetracycline was detected in 37.5% and 12.5% of all MRSA isolates respectively. No resistance to the other antibiotics used in this study and no multidrug resistance was encountered in all MRSA isolates. Conclusion: MRSA nasal carriage among HCWs in this study was 8.7% with no alarming antibiotic resistance pattern. Nurses, less educated and more experienced HCWs are at increased risk of MRSA nasal carriage. Therefore, we strongly recommend screening and decolonizing positive HCWs who can act as asymptomatic carriers in MRSA transmission cycle.

Bull High Inst Public Health Vol.43 No. 1 [2013] MRSA may also show resistance to several other antibiotics making it necessary to use specific antibiotics such as glycopeptides and linezolid to treat MRSA infections.(5) However, resistance to glycopeptides such as vancomycin is emerging and this may lead to further reduction in therapeutic options available for MRSA, which is in particular another serious aspect of MRSA infections.(6) Factors such as improper infection control practices, antibiotic pressure, previous hospitalization and host factors have been suggested to increase the risk of MRSA colonization and spread.(7,8) Colonized healthcare personnel were previously suggested to act as a reservoir, vectors or victims within the transmission cycle of MRSA which may increase the spread of MRSA within the hospital and into community.(9,10) Taking in consideration the resistance pattern of the MRSA, ease of spread and the fatal outcomes of infections caused by MRSA, (9) it is necessary to identify the prevalence and antibiotic resistance pattern of MRSA in HCWs.Screening of asymptomatic HCWs has been recommended by some studies as an essential part of a multifactorial approach in order to protect the health personnel, patients and community, and to encourage the application of better infection prevention precautions.(9,11) The aim of this study is to assess the prevalence of MRSA among healthcare workers at Al-Karak Governmental Hospital in the south of Jordan and to study its antibiotic susceptibility pattern.

Study design, population and location
This cross-sectional study was conducted from March 2012 till June 2012.Results of previous study, conducted in Jordan, showed a prevalence of 5.8% positive MRSA amongst healthcare staff. (12)For our population of 580 with a precision of 2% (95% Confidence Interval specified limits 3.8% -7.8%), the sample size required for this study was 276.

Statistical analysis
The statistical analysis was conducted using STATA10.For categorical variables, Chi Square test was used.For continuous variables that were normally distributed, T test was used to search for significant difference between the groups.

RESULTS:
Our results showed that a total of 24 healthcare workers (HCWs) were MRSA positive which represents 8.7% of the total 276 HCWs who were screened in this study.

( 13 )
Therefore, a total of two hundred seventy six nasal swabs were randomly collected from HCWs at Al-Karak hospital, the tertiary teaching hospital in south of Jordan.All workers included in the study were fulltime employees.Written informed consent was obtained from each participant before nasal specimen collection.The study proposal was reviewed and approved by the Scientific and Ethics Committee of Mu'tah University in Jordan.

2.3 Nares cultures, bacterial strains and antimicrobial susceptibility testing
(16)S.aureus ATCC 25923 was used as control strain.The panel of antibiotics tested included those that are recommended by CLSI or are commonly used locally in empirical treatment of S. aureus infections.Susceptibility testing was done and results were presented for the

Table 1 : Potential variables affecting nasal MRSA carriage amongst HCWs
1 Others: Other professions including doctor, pharmacist, technicians and service employees Significant P value < 0.05