Clonal clusters and gene repertoires of Staphylococcus aureus are essential to understand disease and are well characterized in industrialized countries but poorly analysed in developing regions. The objective of this study was to compare the molecular-epidemiologic profiles of S. aureus isolates from Sub-Saharan Africa and Germany. S. aureus isolates from 600 staphylococcal carriers and 600 patients with community-associated staphylococcal disease were characterized by DNA hybridization, clonal complex (CC) attribution, and principal component (PCA)-based gene repertoire analysis. 73% of all CCs identified representing 77% of the isolates contained in these CCs were predominant in either African or German region. Significant differences between African versus German isolates were found for alleles encoding the accessory gene regulator type, enterotoxins, the Panton-Valentine leukocidin, immune evasion gene cluster, and adhesins. PCA in conjunction with silhouette analysis distinguished nine separable PCA clusters, with five clusters primarily comprising of African and two clusters of German isolates. Significant differences between S. aureus lineages in Africa and Germany may be a clue to explain the apparent difference in disease between tropical/(so-called) developing and temperate/industrialized regions. In low-resource countries further clinical-epidemiologic research is warranted not only for neglected tropical diseases but also for major bacterial infections.

Staphylococcus aureus is a major bacterial pathogen causing a variety of diseases ranging from wound infections to severe bacteremia or intoxications. Besides host factors, the course and severity of disease is also widely dependent on the genotype of the bacterium. Whole-genome sequencing (WGS), followed by bioinformatic sequence analysis, is currently the most extensive genotyping method available. To identify clinically relevant staphylococcal virulence and resistance genes in WGS data, we developed an in silico typing scheme for the software SeqSphere ؉ (Ridom GmbH, Münster, Germany). The implemented target genes (n ‫؍‬ 182) correspond to those queried by the Identibac S. aureus Genotyping DNA microarray (Alere Technologies, Jena, Germany). The in silico scheme was evaluated by comparing the typing results of microarray and of WGS for 154 human S. aureus isolates. A total of 96.8% (n ‫؍‬ 27,119) of all typing results were equally identified with microarray and WGS (40.6% present and 56.2% absent). Discrepancies (3.2% in total) were caused by WGS errors (1.7%), microarray hybridization failures (1.3%), wrong prediction of ambiguous microarray results (0.1%), or unknown causes (0.1%). Superior to the microarray, WGS enabled the distinction of allelic variants, which may be essential for the prediction of bacterial virulence and resistance phenotypes. Multilocus sequence typing clonal complexes and staphylococcal cassette chromosome mec element types inferred from microarray hybridization patterns were equally determined by WGS. In conclusion, WGS may substitute array-based methods due to its universal methodology, open and expandable nature, and rapid parallel analysis capacity for different characteristics in once-generated sequences. Staphylococcus aureus is a Gram-positive facultative pathogenic bacterium that is responsible for a high percentage of hospitaland community-acquired infections worldwide. An infection with S. aureus may manifest itself in a broad variety of diseases, ranging from rather harmless local skin infections to severe bacteremia or intoxications (1). This extensive spectrum of virulence is owed, in part, to the bacterium's individual equipment with virulence factors. Analyzing these virulence factors is difficult because purified staphylococcal toxins do not essentially cause distinctive symptoms when administered in the absence of the bacterium, and the specific knockout of single virulence factors does not necessarily reduce the bacterial virulence (2). Thus, it seems that the combination of different virulence factors, their regulation and transcription, and their allelic variants play a crucial role in determining the eventually expressed virulence phenotype. Therefore, it is important to determine not only the presence or absence of single key factors, such as, e.g., Panton-Valentine leucocidin (PVL) or certain enterotoxins, but to obtain a comprehensive picture of the exact allelic variants of as many virulence-associated genes and their regulatory systems as possible. With regar...

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Urinary tract infections (UTIs) are among the most common infections in sub-Saharan Africa, but microbiological data to guide treatment decisions are limited. Hence, we investigated the bacterial aetiology and corresponding antimicrobial susceptibility patterns in outpatients with UTIs in Bagamoyo, Tanzania. Urine samples from symptomatic individuals were subjected to microbiological examinations for bacterial species identification using conventional methods and disc diffusion-based resistance testing. Subsequently, urine samples were transferred to Germany for confirmatory diagnostics using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and automated resistance testing. Overall, 104 out of 270 (38.5%) individuals had a positive urine culture and 119 putative pathogens were identified. The most frequently detected bacteria were Escherichia coli (23%), Klebsiella spp. (7%), Enterobacter cloacae complex (3%) and Staphylococcus aureus (2%). E. coli isolates showed high resistance against cotrimoxazole (76%), ampicillin (74%), piperacillin (74%) and fluoroquinolones (37%), but widespread susceptibility to meropenem (100%), fosfomycin (98%), piperacillin/tazobactam (97%) and amoxicillin/clavulanic acid (82%). The agreement between E. coli susceptibility testing results in Tanzania and Germany was ≥95%, except for piperacillin/tazobactam (89%) and ciprofloxacin (84%). Given the considerable resistance to frequently prescribed antibiotics, such as cotrimoxazole and fluoroquinolones, future research should explore the potential of oral alternatives (e.g., fosfomycin) for the treatment of UTIs in Tanzania.

Appropriate antimicrobial agents and surgical services to perform I&D were available for the majority of patients. Results from susceptibility testing should be considered more efficiently in the selection of antimicrobial therapy.

Background : Information about prevalence, antibiotic resistance and genotyping data of Staphylococcus aureus (S aureus) isolated from different infections and colonization, both in humans and animals is scarce in Tanzania. Given the wide range of infections S aureus can cause and the raise of methicillin resistant S aureus (MRSA) globally, this review was aimed at collecting local published data on the S aureus bacterium to better understand the epidemiology. Methodology: A systematic review of scientific studies reporting on prevalence, antibiotic resistance and genotyping of S aureus in human and animal infection and colonization was done. Literatures extracted from electronic databases such as PubMed and Google Scholar were screened for eligibility and relevant articles included into the review. The review is limited to literatures published in English, between the years 2010 and 2018. . Results: 39 studies conducted in 5 of the 9 administrative zones in Tanzania were reviewed to establish S aureus prevalence in human and animal infection and colonization. Prevalence in human ranged from 1 - 60%. Antibiotic resistance patterns of S aureus isolated from colonized humans showed higher resistance rates against erythromycin (49%), co-trimoxazole (38%) and tetracycline (28%) compared to report from other studies outside Africa. The review suggests an increased MRSA prevalence of up to 33% compared to 16% reported in previous years. Genotypic data reviewed suggested that MRSA predominantly belonged to ST88. S aureus prevalence in animal studies ranged from 33 - 49% whereas MRSA prevalence ranged from 4 - 35%. Generally low antibiotic resistance levels were reported in these studies with exception to penicillin (85%) and ampicillin (73%). Resistance against tetracycline reported at 30% collaborates the suggested overuse of the drug in livestock keeping in Tanzania. Conclusion : Prevalence of MRSA in Tanzania is rising although clear variations between different geographic areas could be observed. Non-susceptibility to commonly prescribed antibiotics in community associated S aureus is of concern. Research strategies to better understand the S aureus epidemiology by including genotypic characterisations, as well as strengthening antimicrobial resistance surveillance and antimicrobial stewardship are recommended.

Background Data on the prevalence, genotypes and antibiotic resistance patterns of colonizing and infection-associated Staphylococcus aureus (S. aureus) strains both in humans and animals in Tanzania are scarce. Given the wide range of infections caused by S. aureus and the rise of methicillin-resistant S. aureus (MRSA) globally, this review aims at collecting published data on S. aureus bacterium to improve our understanding of its epidemiology in Tanzania. Main body We carried out a systematic review of scientific studies reporting on prevalence, antibiotic resistance and genotyping data pertaining to S. aureus in human and animal infection and colonization. The literature extracted from electronic databases such as PubMed and Google Scholar was screened for eligibility and relevant articles were included. The review is limited to manuscripts published in English language between the years 2010 and 2020. A total of 45 studies conducted in 7 of the 9 administrative zones in Tanzania were reviewed to gather data on S. aureus prevalence in humans and animals. Prevalence in humans ranged from 1 to 60%. Antibiotic resistance patterns of S. aureus isolated from colonized humans showed high resistance rates against co-trimoxazole (46%) and erythromycin (41%) as compared to reports from studies conducted outside Africa. The review suggests an increased MRSA prevalence of up to 26% as compared to 6–16% reported in previous years. Genotypic data reviewed suggested that MRSA predominantly belonged to ST88. The prevalence of S. aureus in animal studies ranged from 33 to 49%, with 4 to 35% of MRSA isolates. Most studies reported low antibiotic resistance levels, with the exception of penicillin (85%) and ampicillin (73%). Conclusion The prevalence of S. aureus and MRSA in Tanzania is rising, although clear variations between different geographic areas could be observed. Non-susceptibility to commonly prescribed antibiotics in community-associated S. aureus is of concern. Research strategies to ameliorate our knowledge on S. aureus epidemiology should employ regular antibiotic resistance surveillance, antimicrobial stewardship as well as genotypic characterization.

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