Community-onsetStaphylococcus aureusinfections presenting to general practices in South-eastern Australia

Abstract

SUMMARYCommunity-acquired Staphylococcus aureus infections are a public health concern, yet little is known about infections that do not present to hospital. We identified community-onset S. aureus infections via specimens submitted to a community-based pathology service. Referring doctors confirmed eligibility and described infection site, severity and treatment. Isolates were characterized on antibiotic resistance, PFGE, MLST/SCCmec, and Panton-Valentine leukocidin (PVL), representing 106 community-onset infections; 34 non-multiresistant methicillin-resistant S. aureus (nmMRSA) (resistant to <3 non-β-lactam antibiotics), 15 multiply antibiotic-resistant MRSA (mMRSA) and 57 methicillin-sensitive S. aureus (MSSA). Most (93%) were skin and soft tissue infections. PVL genes were carried by 42% of nmMRSA isolates [95% confidence interval (CI) 26-61] and 15% of MSSA (95% CI 8-28). PVL was associated with infections of the trunk, head or neck (56·4% vs. 24·3%, P = 0·005) in younger patients (23 vs. 52 years, P < 0·001), and with boils or abscesses (OR 8·67, 95% CI 2·9-26·2), suggesting underlying differences in exposure and/or pathogenesis.

Staphylococcus aureus ‘Down Under’: contemporary epidemiology of S. aureus in Australia, New Zealand, and the South West Pacific

“…It is of note that the prevalence of lukF‐PV/lukS‐PV genes in MSSA isolates was 56%, a rate higher than that reported in a previous New Zealand study, which detected the lukF‐PV/lukS‐PV genes in 37% of disease‐causing MSSA isolates . In a recent Australian study on community‐onset S. aureus infections presenting to general practices in south‐eastern Australia , the MSSA population consisted of 25 different strains, with the lukF‐PV/lukS‐PV genes being detected in at least four clonal clusters and in one singleton (CC1, CC20, CC121, CC30, and ST93). Three of the PVL‐positive lineages (CC1, CC30, and ST93) were also identified in the CA‐MRSA population.…”

A Prescription for Resistance: Management of Staphylococcal Skin Abscesses by General Practitioners in Australia

“…We have previously estimated that about 8% of infections caused by S. aureus in the community of metropolitan Melbourne are MRSA ( Bennett et al, 2014 ), but this is likely to be much higher for abscesses based on our findings here. Given the proportion of COSAHC community-onset infections that are abscesses (66/291, 23%), and the high rate due to MRSA infections (78% compared with 47% of all infections among the frequency-matched COSAHC index cases), we estimate the prevalence of MRSA infections might be as high as 24% (three times higher) in community-onset infections presenting as abscesses in metropolitan Melbourne 2010–2012.…”

“…We have calculated that in 2006, 3–5% of patients presenting with community-onset S. aureus infections in Melbourne had an MRSA infection ( Bennett et al, 2014 ). The preliminary findings of the COSAHC study suggest this has risen to 8–10% by 2010, and may be higher again when aggressive pyogenic soft tissue S. aureus infections have been investigated, showing MRSA the more likely causative organism ( Jahamy et al, 2008 ; del Giudice et al, 2009 ; Coombs et al, 2014 ).…”

Prostatic abscesses and severe sepsis due to methicillin-susceptible Staphylococcus aureusproducing Panton-Valentine leukocidin

“…In the USA, there is a strong association between strains producing PVL and MRSA [14]. In Europe, Australia and Africa, there is a high proportion of MSSA producing PVL [16–19]. In our case the strain producing PVL was susceptible to methicillin.…”