Transmission of methicillin-resistant Staphylococcus aureus in long-term care facilities and their related healthcare networks

Abstract

BackgroundLong-term care facilities (LTCF) are potential reservoirs for methicillin-resistant Staphylococcus aureus (MRSA), control of which may reduce MRSA transmission and infection elsewhere in the healthcare system. Whole-genome sequencing (WGS) has been used successfully to understand MRSA epidemiology and transmission in hospitals and has the potential to identify transmission between these and LTCF.MethodsTwo prospective observational studies of MRSA carriage were conducted in LTCF in England and Ireland. MRSA isolates were whole-genome sequenced and analyzed using established methods. Genomic data were available for MRSA isolated in the local healthcare systems (isolates submitted by hospitals and general practitioners).ResultsWe sequenced a total of 181 MRSA isolates from the two study sites. The majority of MRSA were multilocus sequence type (ST)22. WGS identified one likely transmission event between residents in the English LTCF and three putative transmission events in the Irish LTCF. WGS also identified closely related isolates present in colonized Irish residents and their immediate environment. Based on phylogenetic reconstruction, closely related MRSA clades were identified between the LTCF and their healthcare referral network, together with putative MRSA acquisition by LTCF residents during hospital admission.ConclusionsThese data confirm that MRSA is transmitted between residents of LTCF and is both acquired and transmitted to others in referral hospitals and beyond. Our data present compelling evidence for the importance of environmental contamination in MRSA transmission, reinforcing the importance of environmental cleaning. The use of WGS in this study highlights the need to consider infection control in hospitals and community healthcare facilities as a continuum.Electronic supplementary materialThe online version of this article (doi:10.1186/s13073-016-0353-5) contains supplementary material, which is available to authorized users.

Challenges and Strategies for Prevention of Multidrug-Resistant Organism Transmission in Nursing Homes

“…Such data supports consideration of regional approaches to infection prevention and control [7]. Two independent studies of the genetic heterogeneity of MRSA strains in regional nursing homes and hospitals reached similar conclusions [33•, 34]. Similarly, several epidemiological investigations of carbapenem-resistant Gram-negative bacteria also highlight the interconnectedness of acute care hospitals and post-acute and long-term care settings, including nursing homes.…”

Dynamic Transmission of Staphylococcus Aureus in the Intensive Care Unit

“…Four pairs of S. aureus linked hand-touch sites and patients, and all of these involved sites within the patients' own, or adjoining, bed spaces (Table 3). One pair was classified as "uncertain" according to genomic identity definitions [14]. There were two linked isolates from bed table and cardiac monitor in adjoining bed spaces and another pair recovered from a bed table and bedrail on the same day, three bed spaces apart.…”

Contribution of whole-genome sequencing to understanding of the epidemiology and control of meticillin-resistant Staphylococcus aureus

“…Sometimes these patients require readmission and there is constant flux between the acute and long-stay sector. Many studies have highlighted this dynamic in terms of the acquisition and transmission of MRSA between these sectors [56][57][58][59][60][61][62]. Furthermore, there has been interest in the role of carriage, including enteric carriage [44,50].…”