Nasal Carriage of Methicillin-resistant Staphylococcus
aureus in Healthcare Workers

Keimyung Medical Journal 2010;29(1):1-6.

Nasal Carriage of Methicillin-resistant Staphylococcus aureus in Healthcare Workers

Nam Hee Ryoo; Jung Sook Ha; Seong Yeol Ryu; Chun Soo Kim; Ki Young Kwon; Soon Im Choi

Abstract

Objectives : Methicillin-resistant Staphylococcus aureus (MRSA) colonization is considered to be a significant risk factor for MRSA infections in patients. The anterior nares is the most frequent carriage site for S. aureus. This study was undertaken to ascertain a point prevalence of MRSA colonization among healthcare workers working in intensive care units (ICUs) of a tertiary teaching hospital. Materials and Methods : A total of 270 ICU staffs (145 doctors and 125 nurses) working in 6 different ICUs were included; and swabs of the anterior nares were taken from the staffs for culture. Mannitol-salt agar; catalase and coagulase tests were used to identify S. aureus and cefoxitin disk was used to detect methicillin resistance. All procedures were followed as directed in CLSI guidelines.
Results
: The colonization of S. aureus was found in 58 of 270 staffs (21.5%). Thirteen of 58 isolates of S. aureus were methicillin resistant; so the prevalence of MRSA carriage among ICU healthcare workers was 4.8%: 2.1% (3/145) for doctors and 8% (10/125) for nurses. The highest rate of nasal carriage of MRSA was seen in cardiovascular care unit whereas chest surgery ICU had no prevalence of MRSA at all. Discussion : The annual prevalence of MRSA infection was about 78% in ICU of our hospital; but the nasal carriage of MRSA among healthcare workers in ICU was 4.8%. The prevalence of MRSA colonization was rather higher in nurses than doctors which could be due to the frequent contact and close relation with the patients. Therefore; more attention and annual follow-up surveillance together with molecular studies will be needed to have infection-control; to minimize MRSA prevalence and to clarify the endemic clonality if an outbreak of MRSA infection occurs within the hospital.

Key Words: ICU, Korea, medical staffs, MRSA, nasal carriage, prevalence