Background: Staphylococcus aureus, a leading cause of community-acquired and nosocomial infections, remains a major health problem worldwide. Molecular typing methods, such as spa typing, are vital for the control and, when typing can be made more timely, prevention of S. aureus spread around healthcare settings. The current study aims to review the literature to report the most common clinical spa types around the world, which is important for epidemiological surveys and nosocomial infection control policies.Methods: A search via PubMed, Google Scholar, Web of Science, Embase, the Cochrane library, and Scopus was conducted for original articles reporting the most prevalent spa types among S. aureus isolates. The search terms were “Staphylococcus aureus, spa typing.”Results: The most prevalent spa types were t032, t008 and t002 in Europe; t037 and t002 in Asia; t008, t002, and t242 in America; t037, t084, and t064 in Africa; and t020 in Australia. In Europe, all the isolates related to spa type t032 were MRSA. In addition, spa type t037 in Africa and t037and t437 in Australia also consisted exclusively of MRSA isolates. Given the fact that more than 95% of the papers we studied originated in the past decade there was no option to study the dynamics of regional clone emergence.Conclusion: This review documents the presence of the most prevalent spa types in countries, continents and worldwide and shows big local differences in clonal distribution.

Infections caused by Staphylococcus aureus remain a major global healthcare problem. We aimed to find the common lineages of S. aureus strains circulating in a burn hospital in Tehran. A total of 167 isolates of S. aureus obtained from patients, healthcare workers (HCWs) and environment in Shahid Motahari burn hospital were genotyped by using spa, agr and staphylococcal cassette chromosome mec (SCCmec) typing methods. Antimicrobial susceptibility testing was performed by using the disc diffusion method. The frequency of methicillin-resistant S. aureus (MRSA) was 64.7% (n = 108), with distribution frequencies among patient, HCW and surface isolates of 64.2% (n = 79), 50% (n = 7) and 73.3% (n = 22), respectively. SCCmec type III (75%, n = 81) was found to be the most frequent SCCmec type among MRSA isolates, followed by SCCmec type I (20.4%, n = 22) and SCCmec type IV (1.8%, n = 2). The remaining MRSA isolates (2.8%, n = 3) were nontypeable by this method. About 78.4% (n = 131), 10.2% (n = 17) and 4.8% (n = 8) of all isolates were characterized as agr types I, II and III, respectively, and the other isolates (6.6%) were nontypeable. spa types t030 and t037 constituted the first and second most predominant spa types found in 56.4% (n = 57) and 25.6% (n = 26) of isolates, respectively. We also report here a novel spa type, t16471. The most prevalent genotypes of the isolates found among patient, surface and HCW samples were SCCmec type III/t030, t037/agr type I. Continuous tracking of epidemic isolates and better hospital infection control policies are recommended to efficiently prevent the spread of bacteria to inpatients.

Background: Salmonella and Shigella infections are important public health concerns among children. The emergence of antibiotic resistance amongst Salmonella and particularly Shigella isolates has posed serious problems in antimicrobial treatment worldwide. Data on local antibiotic resistance patterns are essential to design suitable antibiotic treatment guidelines. Objectives: The aim of the present study was to determine the prevalence and drug susceptibility patterns of Shigella and Salmonella species in addition to the detection of extended-spectrum β-lactamase producing isolates among diarrhea samples of pediatric patients. Methods: A total of 5300 diarrheic samples from children were examined for the presence of Salmonella and Shigella species. Biochemical and microbial tests, as well as specific polyvalent antisera, were used for the identification of the bacterial species. Antibiotic susceptibility tests and extended-spectrum β-lactamase detection were conducted by disc diffusion and combination disc methods, respectively. Results: A total of 371 (7%) and 472 (8.9%) samples were positive for Salmonella and Shigella species, respectively. The most prevalent Salmonella isolate was serogroup D (n: 176, 47.5%). Of the Shigella isolates, 60.8% were found as Shigella sonnei and 39.2% as Shigella flexneri. The highest level of antibiotic resistance was noted among Shigella flexneri isolates. Overall, 35.7% of the Shigella flexneri isolates and 31% of the Shigella sonnei isolates produced extended-spectrum β-lactamases. Conclusions: This study provided information on the prevalence and antimicrobial susceptibility patterns of Salmonella and Shigella isolates in Iran. It also indicated a high-level resistance among Shigella isolates to co-trimoxazole and ampicillin and among Salmonella isolates to nalidixic acid.

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