Outbreak of clonal complex 22 Panton–Valentine leucocidin-positive methicillin-resistant Staphylococcus aureus

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

<div class="section"> <a class="named-anchor" id="section1-1757177417695647">  </a> <h5 class="section-title" id="d7354163e128">Aims:</h5> <p id="d7354163e130">We describe the investigation and control of a nosocomial outbreak of Sequence Type (ST) 22 MRSA containing the Panton–Valentine leucocidin (PVL) toxin in an acute multispecialty surgical ward at University Hospital Birmingham NHS Foundation Trust. </p> </div><div class="section"> <a class="named-anchor" id="section2-1757177417695647">  </a> <h5 class="section-title" id="d7354163e133">Methods:</h5> <p id="d7354163e135">A patient was classed as acquiring methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) if they had a negative admission screen and then had MRSA isolated from a subsequent screen or clinical specimen. Spa typing and pulsed field gel electrophoresis (PFGE) was undertaken to confirm MRSA acquisitions. </p> </div><div class="section"> <a class="named-anchor" id="section3-1757177417695647">  </a> <h5 class="section-title" id="d7354163e141">Findings:</h5> <p id="d7354163e143">The Infection Prevention and Control Team were alerted to the possibility of an outbreak when two patients acquired MRSA while being on the same ward. In total, five patients were involved in the outbreak where four patients acquired the PVL-MRSA clone from an index patient due to inadequate infection control practice. Two patients who acquired the strain developed a bloodstream infection. Infection control measures included decolonisation of affected patients, screening of all patients on the ward, environmental sampling and enhanced cleaning. </p> </div><div class="section"> <a class="named-anchor" id="section4-1757177417695647">  </a> <h5 class="section-title" id="d7354163e146">Discussion:</h5> <p id="d7354163e148">Our study highlights the potential risk of spread and pathogenicity of this clone in the healthcare setting. Spa typing and PFGE assisted with confirmation of the outbreak and implementation of infection control measures. In outbreaks, microbiological typing should be undertaken as a matter of course as without specialist typing identification of the described outbreak would have been delayed. </p> </div>

Related collections

Most cited references 16

Record: found
Abstract: not found
Article: not found

Effectiveness of a hospital-wide programme to improve compliance with hand hygiene

Thomas V Perneger, Sylvie Touveneau, Valerie Sauvan … (2000)

0 comments Cited 226 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Current concepts on the virulence mechanisms of meticillin-resistant Staphylococcus aureus.

R Salata, Eleanor Watkins, Michael David (2012)

Meticillin-resistant Staphylococcus aureus (MRSA) strains are prevalent bacterial pathogens that cause both health care and community-associated infections. Increasing resistance to commonly prescribed antibiotics has made MRSA a serious threat to public health throughout the world. The USA300 strain of MRSA has been responsible for an epidemic of community-associated infections in the US, mostly involving skin and soft tissue but also more serious invasive syndromes such as pneumonia, severe sepsis and endocarditis. MRSA strains are particularly serious and potentially lethal pathogens that possess virulence mechanisms including toxins, adhesins, enzymes and immunomodulators. One of these is Panton-Valentine leukocidin (PVL), a toxin associated with abscess formation and severe necrotizing pneumonia. Earlier studies suggested that PVL was a major virulence factor in community-associated MRSA infections. However, some recent data have not supported this association while others have, leading to controversy. Therefore, investigators continue to search for additional mechanisms of pathogenesis. In this review, we summarize the current understanding of the biological basis of MRSA virulence and explore future directions for research, including potential vaccines and antivirulence therapies under development that might allow clinicians to more successfully treat and prevent MRSA infections.

0 comments Cited 46 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Evaluation of molecular typing methods in characterizing a European collection of epidemic methicillin-resistant Staphylococcus aureus strains: the HARMONY collection.

F Cuny, Sara Hæggman, Brian O'Connell … (2007)

We analyzed a representative sample of methicillin-resistant Staphylococcus aureus (MRSA) from 11 European countries (referred to as the HARMONY collection) using three molecular typing methods used within the HARMONY group to examine their usefulness for large, multicenter MRSA surveillance networks that use these different laboratory methodologies. MRSA isolates were collected based on their prevalence in each center and their genetic diversity, assessed by pulsed-field gel electrophoresis (PFGE). PFGE groupings (< or = 3 bands difference between patterns) were compared to those made by sequencing of the variable repeats in the protein A gene spa and clonal designations based on multilocus sequence typing (MLST), combined with PCR analysis of the staphylococcal chromosome cassette containing the mec genes involved in methicillin resistance (SCCmec). A high level of discrimination was achieved using each of the three methodologies, with discriminatory indices between 89.5% and 91.9% with overlapping 95% confidence intervals. There was also a high level of concordance of groupings made using each method. MLST/SCCmec typing distinguished 10 groups containing at least two isolates, and these correspond to the majority of nosocomial MRSA clones described in the literature. PFGE and spa typing resolved 34 and 31 subtypes, respectively, within these 10 MRSA clones, with each subtype differing only slightly from the most common pattern using each method. The HARMONY group has found that the methods used in this study differ in their availability and affordability to European centers involved in MRSA surveillance. Here, we demonstrate that the integration of such technologies is achievable, although common protocols (such as we have developed for PFGE) may also be important, as is the use of centralized Internet sites to facilitate data analysis. PFGE and spa-typing data from analysis of MRSA isolates from the many centers that have access to the relevant equipment can be compared to reference patterns/sequences, and clonal designations can be made. In the majority of cases, these will correspond to those made by the (more expensive) method of choice-MLST/SCCmec typing-and these alternative methods can therefore be used as frontline typing systems for multicenter surveillance of MRSA.