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Clinical microbiologists are engaged in the field of diagnostic microbiology to determine whether pathogenic microorganisms are present in clinical specimens collected from patients with suspected infections. If microorganisms are found, these are identified and susceptibility profiles, when indicated, are determined. During the past two decades, technical advances in the field of diagnostic microbiology have made constant and enormous progress in various areas, including bacteriology, mycology, mycobacteriology, parasitology, and virology. The diagnostic capabilities of modern clinical microbiology laboratories have improved rapidly and have expanded greatly due to a technological revolution in molecular aspects of microbiology and immunology. In particular, rapid techniques for nucleic acid amplification and characterization combined with automation and user-friendly software have significantly broadened the diagnostic arsenal for the clinical microbiologist. The conventional diagnostic model for clinical microbiology has been labor-intensive and frequently required days to weeks before test results were available. Moreover, due to the complexity and length of such testing, this service was usually directed at the hospitalized patient population. The physical structure of laboratories, staffing patterns, workflow, and turnaround time all have been influenced profoundly by these technical advances. Such changes will undoubtedly continue and lead the field of diagnostic microbiology inevitably to a truly modern discipline. Advanced Techniques in Diagnostic Microbiology provides a comprehensive and up-to-date description of advanced methods that have evolved for the diagnosis of infectious diseases in the routine clinical microbiology laboratory. The book is divided into two sections. The first techniques section covers the principles and characteristics of techniques ranging from rapid antigen testing, to advanced antibody detection, to in vitro nucleic acid amplification techniques, and to nucleic acid microarray and mass spectrometry. Sufficient space is assigned to cover different nucleic acid amplification formats that are currently being used widely in the diagnostic microbiology field. Within each technique, examples are given regarding its application in the diagnostic field. Commercial product information, if available, is introduced with commentary in each chapter. If several test formats are available for a technique, objective comparisons are given to illustrate the contrasts of their advantages and disadvantages. The second applications section provides practical examples of application of these advanced techniques in several "hot" spots in the diagnostic field. A diverse team of authors presents authoritative and comprehensive information on sequence-based bacterial identification, blood and blood product screening, molecular diagnosis of sexually transmitted diseases, advances in mycobacterial diagnosis, novel and rapid emerging microorganism detection and genotyping, and future directions in the diagnostic microbiology field. We hope our readers like this technique-based approach and your feedback is highly appreciated. We want to thank the authors who devoted their time and efforts to produce their chapters. We also thank the staff at Springer Press, especially Melissa Ramondetta, who initiated the whole project. Finally, we greatly appreciate the constant encouragement of our family members through this long effort. Without their unwavering faith and full support, we would never have had the courage to commence this project

Six cases of Neisseria meningitidis serogroup W135 meningococcal infection have been reported in Turkey since 2003. Seven isolates recovered from four meningococcal meningitis patients and two asymptomatic carriers produced three distinct pulsed-field gel electrophoresis (PFGE) patterns. Multilocus sequence typing and antigen gene sequencing showed that five isolates were indistinguishable from ST-11 (ET-37) serogroup W135 meningococci, which were first isolated in Saudi Arabia and were responsible for the worldwide outbreak among Hajj pilgrims and their contacts in 2000. The remaining two isolates, which had related PFGE patterns, differed from each other at only one of the genetic loci characterized but were not related to the ST-11 clonal complex. None of the six individuals recalled contact with a pilgrim or had traveled on the Hajj. These six individuals exhibited no time or place relationships to each other, except for the two asymptomatic carriers, who were soldiers and served in the same military unit. These data demonstrate that serogroup W135 meningococci with different genotypes, including the Hajj epidemic strain, are endemic in Turkey.

Military facilities provide unique opportunities for studying Staphylococcus aureus nasal colonization and transmission patterns. In this cross-sectional observational study, we assessed the prevalence of S. aureus nasal colonization among Chinese military volunteers in two camps in the Beijing area. Antimicrobial resistance patterns, risk factors for colonization, and transmission patterns using pulsed-field gel electrophoresis were also evaluated. From May to July 2007, 1,044 nasal swabs were collected from military volunteers from suburban (560) and urban (484) camps. A total of 209 S. aureus isolates were recovered, of which all were methicillin susceptible. Independent factors associated with methicillin-susceptible S. aureus (MSSA) nasal colonization included younger age (odds ratio [OR] = 1.51, 95% confidence interval [95% CI] = 1.03 to 2.21, P = 0.0347), higher education (OR = 1.38, 95% CI = 1.10 to 1.73, P = 0.0056), shorter length of service (OR = 1.74, 95% CI = 1.28 to 2.36, P = 0.0004), nonsmoking (OR = 1.61, 95% CI = 1.14 to 2.28, P = 0.0069), and inactive participation in social events (OR = 2.40, 95% CI = 1.25 to 5.49, P = 0.0082). Among 209 MSSA isolates, 126 (60.3%) were determined to be epidemic and a total of 12 genotypes were identified, of which four (90 isolates [71.4%]) represented the majority of strains. Length of service and camp location were statistically related to the four major MSSA genotype clonal transmissions. Our data indicated that MSSA, not methicillin-resistant S. aureus (MRSA), nasal colonization and clonal transmission occur in healthy military volunteers in Beijing. Younger, female, nonsmoking volunteers with higher education, little or no participation in social events, and less time in service are at higher risk for nasal MSSA carriage.