Distribution of genes associated with invasive disease or nasal carriage status in relation to CCs.

<p>Black circle indicates that all isolates within the CC harbor the gene and white circle that none of the isolates does. A divided circle indicates variable gene presence within the CC. In most cases the presence of virulence genes was linked to CC affiliation.</p

Number of positive blood cultures that yielded <i>S. aureus</i> (number of episodes of SAB) in Örebro County, relative to the total blood-culturing rate in concurrent years.

<p>Number of positive blood cultures that yielded <i>S. aureus</i> (number of episodes of SAB) in Örebro County, relative to the total blood-culturing rate in concurrent years.</p

Layout of the protein microarray.

<p>(A) Positions of each substance on the chip. (B) Legend to the probes. (C) Picture of a processed fluorescent microarray. (D) Bar graph with signal intensities for the expressed proteins.</p

Distribution of SAB isolates assigned to CCs during the study period.

<p>Of 6 predominant CCs (CC5, CC8, CC15, CC25, CC30, and CC45), SAB isolates assigned to CC5 and CC15 showed a trend towards an increased prevalence over the study period, and isolates assigned to CC8, CC25, and CC30 declined. The numbers in parentheses indicate the total number of isolates within each CC. CC30 includes CC30 (ST34/42). Other CCs: CC1, CC6, CC7, CC9, CC12, CC20, CC22, CC49, CC50, CC59, CC97, CC101, CC121, CC182, CC188, CC395, CC398, and ST2319.</p

Alpha Toxin yields by CC/ST affiliation.

<p>Alpha Toxin yields by CC/ST affiliation.</p

Distribution of <i>agr</i> groups (alleles) and presence of virulence genes among SAB isolates from four different time periods.

1<p>Incident rate ratio estimated with Poisson regression analysis.</p>2<p>Poisson regression analysis.</p>3<p>CC6, CC7, CC8, CC20, CC22, CC25, CC45, CC59, CC97, CC101, CC182, CC188, CC395, CC398, ST2319.</p>4<p>CC5, CC9, CC12, CC15, CC49.</p>5<p>CC1, CC30, including CC30 (ST34/42).</p>6<p>CC50, CC121.</p>7<p>Three isolates in CC20 and 6 isolates in CC395 were negative for <i>lukD</i>, but positive for <i>lukE</i>; results were counted for <i>lukE</i>.</p>8<p>The haemolysin gene <i>hlb</i> was excluded from the analysis on the grounds of poor probe performance, which yielded several ambiguous results.</p>9<p>Also known as enterotoxin <i>sep.</i></p>10<p>Seven isolates in CC50 showed a partial deletion of the <i>egc</i> cluster missing <i>seg.</i></p>11<p>Locus tag SACOL1057, GenBank CP000046.1: Position 1063016–1064026.</p>12<p>Locus tag SACOL1056, GenBank CP000046.1: Position 1061753–1062934.</p>13<p>Locus tag SACOL1970, GenBank CP000046.1: Position 2034319–2035485.</p>14<p>Numbers in brackets show the number of ambiguous results, which were not included</p><p>Bold values are statistically significant.</p><p>Distribution of <i>agr</i> groups (alleles) and presence of virulence genes among SAB isolates from four different time periods.</p

Characteristics of patients with blood cultures positive for <i>S. aureus</i>

1<p>Age data are missing for 3 patients from 1980-81.</p><p>Characteristics of patients with blood cultures positive for <i>S. aureus</i></p

Alpha Toxin yields and clinical outcome (veterinary isolates excluded).

<p>Alpha Toxin yields and clinical outcome (veterinary isolates excluded).</p

<i>Staphylococcus aureus In Vitro</i> Secretion of Alpha Toxin (hla) Correlates with the Affiliation to Clonal Complexes

<div><p>The alpha toxin of <i>Staphylococcus aureus</i> is a pore forming toxin that penetrates host cell membranes causing osmotic swelling, rupture, lysis and subsequently cell death. Haemolysin alpha is toxic to a wide range of different mammalian cells; i.e., neurotoxic, dermonecrotic, haemolytic, and it can cause lethality in a wide variety of animals. In this study, the <i>in vitro</i> alpha toxin production of 648 previously genotyped isolates of <i>S. aureus</i> was measured quantitatively using antibody microarrays. Isolates originated from medical and veterinary settings and were selected in order to represent diverse clonal complexes and defined clinical conditions. Generally, the production of alpha toxin <i>in vitro</i> is related to the clonal complex affiliation. For clonal complexes CC22, CC30, CC45, CC479, CC705 and others, invariably no alpha toxin production was noted under the given <i>in vitro</i> conditions, while others, such as CC1, CC5, CC8, CC15 or CC96 secreted variable or high levels of alpha toxin. There was no correlation between alpha toxin yield and clinical course of the disease, or between alpha toxin yield and host species.</p></div

Molecular Typing of MRSA and of Clinical <i>Staphylococcus aureus</i> Isolates from Iaşi, Romania

<div><p>Romania is one of the countries with the highest prevalence of methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) in the world. To obtain data on affiliation of MRSA to strains and clonal complexes and on the population of methicillin susceptible <i>S. aureus</i> (MSSA), clinical isolates from bloodstream infections, skin and soft tissue infections as well as from screening swabs were collected at hospitals in Ia?i, a city in the North-Eastern part of Romania. Isolates were characterised by microarray hybridisation. Nearly half of all isolates (47%), and about one third (34%) of bloodstream isolates were MRSA. The prevalence of the Panton-Valentine leukocidin (PVL) was also high (31% among MRSA, 14% among MSSA). The most common MRSA strain was a PVL-negative CC1-MRSA-IV that might have emerged locally, as a related MSSA was also common. PVL-positive CC8-MRSA-IV (“USA300”) and PVL-negative ST239-like MRSA-III were also frequently found while other MRSA strains were only sporadically detected. Among MSSA, PVL-positive CC121 as well as PVL-negative CC1, CC22 and CC45 predominated. Although this study provides only a snapshot of <i>S. aureus</i>/MRSA epidemiology in Romania, it confirms the high burden of MRSA and PVL on Romanian healthcare settings.</p></div