title: Prevalence, prediction, and clonality of methicillin-resistant Staphylococcus aureus carriage at admission to medical units in Hong Kong, China.
abstract: OBJECTIVE
  To determine the prevalence, risk factors, and molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) colonization at the time of admission to acute medical units and to develop a cost-effective screening strategy.
  
  
  METHODS
  Nasal and groin screening cultures were performed for patients at admission to 15 acute medical units in all 7 catchment regions in Hong Kong. All MRSA isolates were subjected to spa typing.
  
  
  RESULTS
  The overall carriage rate of MRSA was 14.3% (95% confidence interval [CI], 13.5-15.1). MRSA history within the past 12 months (adjusted odds ratio [OR], 4.60 [95% CI, 3.28-6.44]), old age home residence (adjusted OR, 3.32 [95% CI, 2.78-3.98]), and bed-bound state (adjusted OR, 2.19 [95% CI, 1.75-2.74]) were risk factors selected as MRSA screening criteria that provided reasonable sensitivity (67.4%) and specificity (81.8%), with an affordable burden (25.2%). spa typing showed that 89.5% (848/948) of the isolates were clustered into the 4 spa clonal complexes (CCs): spa CC1081, spa CC032, spa CC002, and spa CC4677. Patients colonized with MRSA spa types t1081 (OR, 1.77 [95% CI, 1.49-2.09]) and t4677 (OR, 3.09 [95% CI, 1.54-6.02]) were more likely to be old age home residents.
  
  
  CONCLUSIONS
  MRSA carriage at admission to acute medical units was prevalent in Hong Kong. Our results suggest that targeted screening is a pragmatic approach to increase the detection of the MRSA reservoir. Molecular typing suggests that old age homes are epicenters in amplifying the MRSA burden in acute hospitals. Enhancement of infection control measures in old age homes is important for the control of MRSA in hospitals.
authors: Department of Pathology, Princess Margaret Hospital, Hong Kong, China.
authors: Shik
authors: S
authors: Luk
authors: Alex Yat Man
authors: AY
authors: Ho
authors: Tak Keung
authors: TK
authors: Ng
authors: Iris Hoi Ling
authors: IH
authors: Tsang
authors: Eliza Hoi Ying
authors: EH
authors: Chan
authors: Kin Wing
authors: KW
authors: Choi
authors: Ngai Chong
authors: NC
authors: Tsang
authors: Rodney Allan
authors: RA
authors: Lee
authors: Vincent Chi Chung
authors: VC
authors: Cheng
authors: Sau Chun
authors: SC
authors: Fung
authors: Wai Man
authors: WM
authors: Lai
authors: Tak Lun
authors: TL
authors: Que
authors: Andrew Tin Yau
authors: AT
authors: Wong
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015373:Bacterial Typing Techniques; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D003430:Cross-Sectional Studies; D005260:Female; D006707:Homes for the Aged; D006723:Hong Kong / Q000453:epidemiology; D006761:Hospitals; D006801:Humans; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification / Q000235:genetics*; D008875:Middle Aged; D017720:Molecular Epidemiology; D010343:Patient Admission; D015995:Prevalence; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D013205:Staphylococcal Protein A / Q000235:genetics; D013997:Time Factors
chemical_list: D013205:Staphylococcal Protein A