Whole‐genome comparison of meticillin‐resistant Staphylococcus aureus CC22 SCCmecIV from people and their in‐contact pets. Issue 5 (19th July 2013)

• Record Type: Journal Article
• Authors: Loeffler, Anette; McCarthy, Alex; Lloyd, David H.; Musilová, Eva; Pfeiffer, Dirk U.; Lindsay, Jodi A.
• Is Part Of: Veterinary dermatology. Volume 24:Issue 5(2013:Oct.)
• Page Start: 538
• Page End: e128
• Publication Date: 2013-07-19
• Subjects: Veterinary dermatology -- Periodicals; Pet medicine -- Periodicals; 636.08965
• DOI: 10.1111/vde.12062
• Languages: English
• ISSNs: 0959-4493

Abstract

<abstract abstract-type="main" id="vde12062-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="vde12062-sec-0001" sec-type="section"> <title>Background</title> <p>Meticillin‐resistant <italic>Staphylococcus aureus</italic> (MRSA) infections remain important medical and veterinary challenges. The MRSA isolated from dogs and cats typically belong to dominant hospital‐associated clones, in the UK mostly EMRSA‐15 (CC22 SCC<italic>mec</italic>IV), suggesting original human‐to‐animal transmission. Nevertheless, little is known about host‐specific genetic variation within the same <italic>S. aureus</italic> lineage.</p> </sec> <sec id="vde12062-sec-0002" sec-type="section"> <title>Hypothesis/Objectives</title> <p>To identify host‐specific variation amongst MRSA CC22 SCC<italic>mec</italic>IV by comparing isolates from pets with those from in‐contact humans using whole‐genome microarray.</p> </sec> <sec id="vde12062-sec-0003" sec-type="section"> <title>Methods</title> <p>Six pairs of MRSA CC22 SCC<italic>mec</italic>IV from human carriers (owners and veterinary staff) and their respective infected in‐contact pets were compared using a 62‐strain whole‐genome <italic>S. aureus</italic> microarray (SAM‐62). The presence of putative host‐specific genes was subsequently determined in a larger number of human (<italic>n </italic>= 47) and pet isolates (<italic>n </italic>= 93) by PCR screening.</p> </sec> <sec id="vde12062-sec-0004" sec-type="section"> <title>Results</title> <p>Variation in mobile genetic elements (MGEs) occurred frequently and appeared largely independent of host and in‐contact pair. A plasmid (SAP078A) encoding heavy‐metal resistance genes (<italic>arsR</italic>, <italic> arsA</italic>, <italic> cadA</italic>, <italic> cadC</italic>, <italic> mco</italic> and <italic>copB</italic>) was found in three of six human and none of six animal isolates. However, only two of four resistance genes were associated with human hosts (<italic>P </italic>=<italic> </italic>0.015 for <italic>arsA</italic> and <italic>cadA</italic>).</p> </sec> <sec id="vde12062-sec-0005" sec-type="section"> <title>Conclusions and clinical importance</title> <p>The variation found amongst MGEs highlights that genetic adaptation in MRSA continues. However, host‐specific MGEs were not detected, which supports the hypothesis that pets may not be natural hosts of MRSA CC22 and emphasizes that rigorous hygiene measures are critical to prevent contamination and infection of dogs and cats. The host specificity of individual heavy‐metal resistance genes warrants further investigation into different selection pressures in humans and animals.</p> </sec> </abstract>