The prevalence and source of methicillin-resistant Staphylococcus aureus (MRSA) in the community in Hong Kong

Abstract

SUMMARYAlthough reports of isolation of methicillin-resistant Staphylococcus aureus (MRSA) from patients admitted from the community have increased, few studies have investigated colonization of healthy subjects. This study aimed to determine community levels of MRSA in Hong Kong. Nasal swabs from a cross section of young adults and family units were cultured for MRSA. Antibiotic sensitivities and risk factors for carriage were determined and clonal relationships were investigated by pulsed-field gel electrophoresis (PFGE). Overall carriage was low (1 . 4%), and associated with health-care exposures (OR 13 . 56, 95 % CI 1 . 11-165 . 21). Subjects working in health care yielded multi-resistant MRSA strains, but isolates from non-hospital-exposed subjects were methicillin-resistant only. Strains indistinguishable by PFGE were carried by subjects working together, and some spread to other contacts was observed. MRSA colonization in the community is rare in Hong Kong and is largely associated with working in health care. Community-acquired staphylococcal infections may be treated with agents effective against methicillin-sensitive strains.

Successful Multiresistant Community-Associated Methicillin-Resistant Staphylococcus aureus Lineage from Taipei, Taiwan, That Carries Either the Novel Staphylococcal Chromosome Cassette mec (SCC mec ) Type V T or SCC mec Type IV

“…The CAMRSA colonization rate among subjects lacking traditional risk factors was 5.3%, a high rate compared with 0.24% calculated in a meta-analysis (36), 0.6% among children in Chicago (14) in 1999, 3.5% among healthy people in southern Taiwan (19), and 1.4% in Hong Kong (31). It remains to be determined whether this high MRSA colonization rate is widespread in Taipei and other locations in Taiwan or can be found among adults from the same geographic location.…”

Effect of antibiotic prescribing in primary care on meticillin-resistant Staphylococcus aureus carriage in community-resident adults: a controlled observational study

“…A recent paper by O'Donoghue et al [26] examined the association between previous antibiotic use and MRSA carriage in nasal samples from a group of young adults. The study found no association between MRSA carriage and antibiotic use in the previous 4 weeks.…”

Prevalence ofStaphylococcus aureuscarriage among dogs and their owners

“…This has been a cause of concern particularly as levels of MRSA have continued to increase in the community, most notably in the United States [37] and Australia [38]. Although the prevalence of carriage of CA-MRSA remains low in Hong Kong [6], there is still a need for vigilance as infections with community strains of MRSA have recently occurred [39]. In our study, nasal carriage in dogs was assessed, and it was shown that dogs, in particular those owned by HCWs, can act as an important reservoir of the organism.…”

“…Most owners were willing for samples to be collected from both themselves and their dogs, with a small number restricting permission to collection only from their dog. The sample size of 800 was based on a carriage level of 25 % in adult humans [6], and an assumed 25% carriage frequency in dogs belonging to colonized subjects with a 2 % error. For comparison of carriage levels in dogs with limited human contact, 30 stray dogs were sampled for nasal colonization.…”

“…More recently, it has spread into the community (community-associated MRSA, CA-MRSA), and been implicated in reports of severe infections in otherwise healthy persons [5][6][7]. Exposure to health care, including surgery, immunosuppression, antibiotic use, and long-term hospitalization, and healthcare workers (HCWs) is recognized as a risk factor for hospital-associated MRSA colonization [6,8,9], but further work is required to identify reservoirs for CA-MRSA in the community, and their importance as a source of strains imported into the hospital.…”