INTRODUCTIONCommunity-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has emerged worldwide. In contrast to healthcare-associated MRSA (HA-MRSA), CA-MRSA isolates are usually susceptible to multiple non-beta-lactam antibiotics and cause a distinct spectrum of infections in epidemiologically disparate populations - in particular, cutaneous abscesses, necrotising fasciitis and necrotising pneumonia. They arise from a broader genetic background, and possess differing virulence genes. We aim to describe the distribution of different molecular subtypes of CA-MRSA among various regions and discuss briefly the implications of CA-MRSA from a local perspective.

METHODSLiterature review of articles on CA-MRSA, focusing mainly on reports where the genetic background of isolates had been analysed using multi-locus sequence typing (MLST). Singapore data were obtained from the local CA-MRSA database.

RESULTSMLST analysis demonstrated the presence of epidemic subtypes of CA-MRSA within most geographic areas. In parts of the United States, community MRSA infections currently exceed those caused by their methicillin-susceptible counterparts. In Singapore, CA-MRSA infections are increasing, predominantly as a result of the spread of ST30 clones.

CONCLUSIONAvailable evidence suggests that the emergence of MRSA from the community is not going to be a transient phenomenon. Local guidelines for dealing with this phenomenon at both therapeutic and preventive levels are needed prior to the potential development of a situation mirroring that of meso-endemic HA-MRSA in local hospitals or CA-MRSA epidemics in parts of USA.

Bacterial Typing Techniques ; Community-Acquired Infections ; epidemiology ; microbiology ; Cross Infection ; diagnosis ; microbiology ; Humans ; Methicillin Resistance ; Risk Factors ; Singapore ; epidemiology ; Staphylococcal Infections ; epidemiology ; microbiology ; Staphylococcus aureus ; classification ; drug effects

There were many reports of longitudinal changes in the causative organisms of neonatal sepsis in Western countries but few in Asia. We aimed to study longitudinal trends in the epidemiology of neonatal sepsis at Seoul National University Children's Hospital (SNUCH), a tertiary center in Korea, and compared the results to previous studies of Western countries. The medical records of all of the neonates who were hospitalized at SNUCH from 1996 to 2005 with positive blood cultures were reviewed. We also compared the findings to previous 16-yr (1980-1995). One hundred and forty-nine organisms were identified in 147 episodes from 134 infants. In comparison with the previous 16-yr studies, there was a decrease in the number of Escherichia coli infections (16.2% vs 8.7%: odds ratio [OR] 0.495; 95% confidence interval [CI], 0.255-0.962; P = 0.035), but an increase in Staphylococcus aureus (16.6% vs 25.5%: OR 1.720; 95% CI, 1.043-2.839; P = 0.033) and fungal infections (3.3% vs 18.7%: OR 6.740; 95% CI, 2.981-15.239; P < 0.001), predominantly caused by Candida species. In conclusion, the incidence of sepsis caused by E. coli decreases, but S. aureus and fungal sepsis increases significantly. Compared with Western studies, the incidence of sepsis caused by S. aureus and fungus has remarkably increased.
*Hospitals ; Humans ; Infant ; Infant, Newborn ; Infant, Newborn, Diseases/*epidemiology/microbiology ; Intensive Care Units, Neonatal ; Longitudinal Studies ; Mycoses/epidemiology ; Republic of Korea/epidemiology ; Sepsis/*epidemiology/microbiology ; Staphylococcal Infections/epidemiology

OBJECTIVETo genotypically characterize methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from medical and surgical wards in Universiti Kebangsaan Malaysia Medical Centre (UKMMC) in 2009.

METHODSMRSA strains were collected and molecularly typed by pulsed-field gel electrophoresis (PFGE).

RESULTSPFGE typing on 180 MRSA isolated in UKMMC identified 5 pulsotypes (A-E) and 6 singletons, where pulsotypes B and C were suspected to be divergent clones originating from a single ancestor. This study also showed that most MRSA strains were isolated from swab (119 isolates), followed by blood (22 isolates), tracheal aspirate (11 isolates) and sputum (10 isolates). On the other hand, urine and bone isolates were less, which were 4 and 1 isolates, respectively. The distribution of different pulsotypes of MRSA among wards suggested that MRSA was communicated in surgical and medical wards in UKMMC, with pulsotype B MRSA as the dominant strain. Besides, it was found that most deceased patients were infected by pulsotype B MRSA, however, no particular pulsotype could be associated with patient age, underlying disease, or ward of admittance.

CONCLUSIONSFive pulsotypes of MRSA and 6 singletons were identified, with pulsotype B MRSA as the endemic strains circulating in these wards, which is useful in establishment of preventive measures against MRSA transmission.

Electrophoresis, Gel, Pulsed-Field ; Evolution, Molecular ; Hospitals ; Malaysia ; epidemiology ; Methicillin-Resistant Staphylococcus aureus ; genetics ; isolation & purification ; Staphylococcal Infections ; epidemiology ; microbiology

OBJECTIVETo characterize the incidence, epidemiologic features, etiologic agents and sequelae of bacterial meningitis in children under 5 years of age in Nanning, Guangxi.

METHODSA population-based surveillance was conducted to evaluate children with signs and symptoms of meningitis. All hospitals, township health centers and village clinics in the surveillance area were structured to participate in the case referral and evaluation. Cerebrospinal fluid (CSF) and blood specimens were obtained and processed using standardized microbiologic methods.

RESULTSDuring the 26-month surveillance period, among the children under 5 years old, a total of 1272 cases who met the screening criteria of meningitis were studied. 265 of 1272 cases were identified as clinically diagnosed meningitis, with an incidence rate of 86.36 per 100 000 population. The annual incidence rate under the 38 cases of confirmed bacterial meningitis appeared to be 12.38/100 000. Staphylococcus species accounted for the largest proportion of laboratory-confirmed bacterial meningitis, followed by E. coli and S. pneumoniae. The highest attack rate occurred in neonates < 1 month, followed by children aged 1 - 12 months in the confirmed patients. Meningitis caused by Sp and Hi mainly occurred in children aged 1 - 12 months. All cases of meningitis due to Hi and Sp were children aged 1 - 24 months. 13.16% and 0.00% of the cases survived with complications and sequelae, and the case-fatality rate was 18.42%. 40 bacterial isolates were identified from 1193 blood cultures and 23 from 1211 cerebrospinal fluid samples, but no Neisseria meningitidis was found.

CONCLUSIONMeningitis due to Hi was first confirmed in Guangxi with the incidence of 0.98 per 100 000 population. The annual incidence rate of confirmed bacterial meningitis was 12.38 per 100 000, which was considered an important public health problem in children. Staphylococci was the predominant pathogen in confirmed bacterial meningitis.

Child, Preschool ; China ; epidemiology ; Female ; Humans ; Incidence ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial ; epidemiology ; microbiology ; Meningitis, Escherichia coli ; epidemiology ; Meningitis, Haemophilus ; epidemiology ; Population Surveillance ; Staphylococcal Infections ; epidemiology

INTRODUCTIONTreatment of acute lymphoblastic leukaemia (ALL) using intensive chemotherapy has resulted in high cure rates but also substantial morbidity. Infective complications represent a significant proportion of treatment-related toxicity. The objective of this study was to describe the microbiological aetiology and clinical outcome of episodes of chemotherapy-induced febrile neutropaenia in a cohort of children treated for ALL at our institution.

MATERIALS AND METHODSPatients with ALL were treated with either the HKSGALL93 or the Malaysia-Singapore (Ma-Spore) 2003 chemotherapy protocols. The records of 197 patients who completed the intensive phase of treatment, defined as the period of treatment from induction, central nervous system (CNS)-directed therapy to reinduction from June 2000 to January 2010 were retrospectively reviewed.

RESULTSThere were a total of 587 episodes of febrile neutropaenia in 197 patients, translating to an overall rate of 2.98 episodes per patient. A causative pathogen was isolated in 22.7% of episodes. An equal proportion of Gram-positive bacteria (36.4%) and Gram-negative bacteria (36.4%) were most frequently isolated followed by viral pathogens (17.4%), fungal pathogens (8.4%) and other bacteria (1.2%). Fungal organisms accounted for a higher proportion of clinically severe episodes of febrile neutropaenia requiring admission to the high-dependency or intensive care unit (23.1%). The overall mortality rate from all episodes was 1.5%.

CONCLUSIONFebrile neutropaenia continues to be of concern in ALL patients undergoing intensive chemotherapy. The majority of episodes will not have an identifiable causative organism. Gram-positive bacteria and Gram-negative bacteria were the most common causative pathogens identified. With appropriate antimicrobial therapy and supportive management, the overall risk of mortality from febrile neutropaenia is extremely low.

Candidiasis ; epidemiology ; Chemotherapy-Induced Febrile Neutropenia ; epidemiology ; microbiology ; Child ; Cohort Studies ; Escherichia coli Infections ; epidemiology ; Gram-Negative Bacterial Infections ; epidemiology ; Gram-Positive Bacterial Infections ; epidemiology ; Humans ; Influenza, Human ; epidemiology ; Klebsiella Infections ; epidemiology ; Mycoses ; epidemiology ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; Pseudomonas Infections ; epidemiology ; Retrospective Studies ; Singapore ; epidemiology ; Staphylococcal Infections ; epidemiology ; Virus Diseases ; epidemiology

The present study determined the genetic relationships between 41 Staphyloccocus (S.) aureus isolates from bovines, humans, and food using a single enzyme amplified fragment length polymorphism (AFLP) technique. We evaluated the prevalence of staphylococcal enterotoxin (SE) genes and other virulence gene determinants by PCR. The identification of S. aureus was based on culturing and biochemical tests, and by amplifying a specific section of the 23S rRNA gene. PCR amplification of the SE genes (sea, seb, sec, see, seg, seh, and sei) singly or in combination was observed. Most isolates of bovine origin harbored hla (84%) and cap5 (74%), while most isolates from humans harbored hla (73%), cap8 (91%), and fnbA (100%). Strains from food sources were positive for hla (100%), cap5 (100%), and cap8 (64%) unlike isolates from humans or bovines. A single enzyme AFLP analysis revealed a correlation between AFLP clusters of some strains and the source of the isolates The genotypic results of the present study might help to better understand the distribution of prevalent S. aureus clones among humans, bovines, and food and will help control S. aureus infections in Indonesia.
Amplified Fragment Length Polymorphism Analysis ; Animals ; Bacterial Proteins/genetics/metabolism ; Cattle ; Female ; *Food Microbiology ; Gene Expression Regulation, Bacterial ; Humans ; Indonesia/epidemiology ; Mastitis, Bovine/epidemiology/microbiology ; Phylogeny ; Staphylococcal Infections/epidemiology/microbiology/*veterinary ; Staphylococcus aureus/*genetics

OBJECTIVETo investigate the relation between the epidemiological strains of meticillin-resistant Staphylococcus aureus (MRSA) and the strains isolated from the nasal fossa of the medical staff and inpatients.

METHODSThe MRSA strains were isolated from the nasal fossa of the medical staff and inpatients in the Department of Neurosurgery. The genes of the isolated strains were amplified by randomly amplified polymorphic DNA (RAPD) assay.

RESULTSThree and 12 MRSA strains were isolated from the nasal fossa of the medical staff and patients who were hospitalized for more than 1 week, respectively, and RAPD assay revealed high homology between the isolated strains.

CONCLUSIONCross infection can be present between the medical staff, inpatients, and the infected patients.

China ; epidemiology ; Cross Infection ; microbiology ; DNA, Bacterial ; genetics ; isolation & purification ; Humans ; Infectious Disease Transmission, Professional-to-Patient ; Inpatients ; Medical Staff ; Methicillin Resistance ; Nasal Cavity ; microbiology ; Phylogeny ; Random Amplified Polymorphic DNA Technique ; Staphylococcal Infections ; epidemiology ; microbiology ; Staphylococcus aureus ; classification ; genetics ; isolation & purification

Sensitivity to commercial teat dips (nonoxinol-9 iodine complex and chlorhexidine digluconate) of 56 Staphylococcus (S.) aureus strains isolated from quarter milk samples of various German dairy herds treated with different teat dipping schemes was investigated in this study. The minimum inhibitory concentration was determined using a broth macrodilution method according to the German Veterinary Association guidelines. The main objective of the current study was to induce in vitro resistance induction of S. aureus to chemical disinfectants. Ten different strains were repeatedly passed ten times in growth media with sub-lethal concentrations of disinfectants. Nine strains showed a significant reduction in susceptibility to the nonoxinol-9 iodine complex but only one strain developed resistance to chlorhexidine digluconate. Stability of the acquired resistance was observed in all S. aureus strains adapted to the nonoxinol-9 iodine complex and chlorhexidine digluconate. In contrast, simultaneous resistance to different antibiotics was not observed in any of the ten investigated S. aureus strains. However, the isolates exhibited a high degree of resistance to penicillin G. Based on these results, resistance of S. aureus to chemical disinfectants may be more likely to develop if the chemicals are used at concentrations lower than that required for an optimal biocidal effect.
Animals ; Anti-Bacterial Agents/pharmacology ; Cattle ; Chlorhexidine/*pharmacology ; Disinfectants/pharmacology ; Dose-Response Relationship, Drug ; Drug Resistance, Bacterial ; Female ; Germany/epidemiology ; Iodine/chemistry/*pharmacology ; Mastitis, Bovine/epidemiology/*microbiology ; Nonoxynol/*pharmacology ; Staphylococcal Infections/epidemiology/microbiology/*veterinary ; Staphylococcus aureus/classification/*drug effects

BACKGROUND: The BD GeneOhm MRSA PCR assay (Becton Dickinson, USA) is a qualitative real-time PCR test for rapid detection of nasal colonization of methicillin-resistant Staphylococcus aureus (MRSA). We evaluated the performance of BD GeneOhm MRSA PCR assay versus MRSASelect (Bio-Rad, France) and broth enrichment cultures for detection of MRSA from nasal swabs. METHODS: From August 2008 to January 2009, 295 nasal swabs were taken from patients in intensive care units and transported to the laboratory with BD CultureSwab Liquid Stuart Single Swab (Becton Dickinson, USA). The swabs were inoculated onto MRSASelect first and then suspended into GeneOhm sample buffer: 100 microliter of the suspension was inoculated into 6.5% NaCl-tryptic soy broth (Becton Dickinson, USA), which was subcultured on MRSASelect after overnight incubation (TSBS). Performances of GeneOhm MRSA and MRSASelect were compared to TSBS. RESULTS: With GeneOhm MRSA, 125 swabs (44.6%) were positive for MRSA, 13 (4.4%) were unresolved, and 2 were not determined. With MRSASelect and TSBS 86 (29.4%) and 106 swabs (36.2%), respectively, were positive. The sensitivity, specificity, and positive and negative predictive value of GeneOhm MRSA were 85.8%, 77.5%, and 72.8% and 93.5%, respectively, and corresponding values for MRSASelect were 78.3%, 94.8%, and 96.5% and 88.9%. Of the 33 patients whose 34 specimens were found false positive in GeneOhm MRSA, 23 patients were MRSA-positive either previously or subsequently to this study. All of the 10 patients with false-negative specimens in GeneOhm MRSA PCR assay were previously MRSA or methicilln-resistant coagulase negative staphylococci (MRCNS)-positive and were treated for MRSA, but they became MRSA-positive after 1 to 4 negative surveillance cultures. CONCLUSIONS: GeneOhm MRSA PCR assay showed a relatively high negative predictive value. However, its low specificity and frequent occurrence of unresolved results would be problematic in the endemic areas with a high prevalence of MRSA.
Endemic Diseases ; Humans ; Intensive Care Units ; Methicillin-Resistant Staphylococcus aureus/genetics/*isolation & purification ; Nose/*microbiology ; Polymerase Chain Reaction/*methods ; Reagent Kits, Diagnostic ; Sensitivity and Specificity ; Staphylococcal Infections/*diagnosis/epidemiology

BACKGROUNDStaphylococcus aureus is one of the predominant causes of skin and soft tissue infections (SSTIs), but limited data were available regarding the characterization of S. aureus from SSTIs patients in Jiangsu Province in China. We aimed to investigate the molecular epidemiology of S. aureus among SSTIs patients in two hospitals of Jiangsu Province.

METHODSSixty-two patients with SSTIs from two Chinese hospitals in Jiangsu Province were enrolled in this study, and 62 S. aureus isolates were collected from February 2014 to January 2015. S. aureus isolates were characterized by antimicrobial susceptibility testing, toxin gene detection, and molecular typing with sequence type, Staphylococcus protein A gene type, accessory gene regulator (agr) group, and Staphylococcal cassette chromosome mec t ype.

RESULTSSixteen (25.8%) methicillin-resistant S. aureus (MRSA) isolates were detected, and there was no isolate found resistant to vancomycin, teicoplanin, sulfamethoxazole-trimethoprim, and linezolid. The sei was the toxin gene most frequently found, and no lukS/F-PV-positive isolates were detected among the SSTIs' patients. Molecular analysis revealed that ST398 (10/62, 16.1%; 2 MRSA and 8 methicillin-susceptible S. aureus) to be the dominant clone, followed by ST5 (8/62, 12.9%) and ST7 (8/62, 12.9%).

CONCLUSIONSThe livestock ST398 was the most common clone among patients with S. aureus SSTIs in Jiangsu Province, China. Surveillance and further studies on the important livestock ST398 clone in human infections are necessarily requested.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Anti-Bacterial Agents ; pharmacology ; Child ; Child, Preschool ; China ; Female ; Hospitals ; Humans ; Infant ; Linezolid ; pharmacology ; Male ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; isolation & purification ; Microbial Sensitivity Tests ; Middle Aged ; Molecular Epidemiology ; Soft Tissue Infections ; microbiology ; Staphylococcal Infections ; microbiology ; Staphylococcal Skin Infections ; microbiology ; Staphylococcus aureus ; drug effects ; isolation & purification ; Teicoplanin ; pharmacology ; Trimethoprim, Sulfamethoxazole Drug Combination ; pharmacology ; Vancomycin ; pharmacology ; Young Adult