Positive Staphylococci Research Articles

Characterization of a community-acquired-MRSA USA300 isolate from a river sample in Austria and whole genome sequence based comparison to a diverse collection of USA300 isolates

The increasing emergence of multi-resistant bacteria in healthcare settings, in the community and in the environment represents a major health threat worldwide. In 2016, we started a pilot project to investigate antimicrobial resistance in surface water. Bacteria were enriched, cultivated on selective chromogenic media and species identification was carried out by MALDI-TOF analysis. From a river in southern Austria a methicillin resistant Staphylococcus aureus (MRSA) was isolated. Whole genome sequence analysis identified the isolate as ST8, spa type t008, SCCmecIV, PVL and ACME positive, which are main features of CA-MRSA USA300. Whole genome based cgMLST of the water isolate and comparison to 18 clinical MRSA USA300 isolates from the Austrian national reference laboratory for coagulase positive staphylococci originating from 2004, 2005 and 2016 and sequences of 146 USA300 isolates arbitrarily retrieved from the Sequence Read Archive revealed a close relatedness to a clinical isolate from Austria. The presence of a CA-MRSA USA300 isolate in an aquatic environment might pose a public health risk by serving as a potential source of infection or a source for emergence of new pathogenic MRSA clones.

Outcome of EC/EFSA questionnaire (2016) on use of Whole Genome Sequencing (WGS) for food‐ and waterborne pathogens isolated from animals, food, feed and related environmental samples in EU/EFTA countries

Whole Genome Sequencing (WGS) is becoming increasingly used in public health and food safety laboratories. To date, there is a wide variation in the level of implementation of WGS among laboratories from different sectors in different countries, the type of analysis employed and the data interpretation. To gather information on the WGS capacity of food safety/veterinary laboratories in the European Union (EU) and associated countries (EFTA), the European Commission (DG SANTE) and the European Food Safety Authority (EFSA), supported by the EU Reference laboratories (EURLs), prepared a survey among the EU/EFTA laboratory Networks for Salmonella, Listeria monocytogenes, Escherichia coli (VTEC), Campylobacter, Coagulase Positive Staphylococci, Antimicrobial Resistance and bacteriological and viral contaminants of bivalve molluscs. Questions on the general use of WGS, pathogens tackled, analysis purposes, pipelines and tools used, place of data storage and analysis, WGS research projects, needs for support, and future interest to implement WGS were addressed. By the end of 2016, WGS was already in use in reporting laboratories from 17 out of 30 EU/EFTA countries; in particular, WGS was reported to be used in all consulted EURLs, almost half of the National Reference Laboratories (44% affirmative respondents) and only few Official Laboratories (7% affirmative respondents). The main reason for not implementing WGS was the lack of capacity (budget and expertise). WGS was mainly used for outbreak investigations, followed by surveillance, and mostly for L. monocytogenes, E. coli and Salmonella analysis. Sequencing, sequence storage and analysis were mainly done ‘in house’. Several WGS pipelines/platforms/tools were in use for analysis of different microorganisms and purposes. The participating laboratories expressed a general willingness for collaboration with EURLs and European institutions. This report provides a first picture of the state of the art in relation to the use of WGS in European food safety laboratories at the end of 2016.

Evaluation of Bacterial Population in the Saliva of Drug Addicts

Background: The human mouth harbors over 700 microbial genera. The large number of them is normal bacteria; few of them are opportunistic pathogens. Objective: The study was aimed to evaluate the bacterial population of drug addicted persons and compare it to that of a normal healthy person. Methods: Five different samples of human saliva; alcohol drunken person, oral moist snuff user, cigarette, hashish and shisha smoker were investigated the involvement of bacteria in them. One sample was collected from normal non-addict person. The bacterial population in drug addictive persons were compared that on normal non-addictive person. Results: The bacteria observed were: Gram negative cocci, mono cocci, streptococci, vibrio, gram negative rod, gram positive staphylococcus, gram positive streptococci and gram-positive rod. Conclusion: The order of bacterial population was; alcohol drunken person<oral moist snuff user ˂ cigarette smoker ˂ hashish smoker ˂ shisha smoker˂ normal non addictive person. From the findings in this study it is concluded that all these drugs have some antibacterial activities.

Microbiological quality assessment of milk at different stages of the dairy value chain in a developing country setting

The main objective of the study was to assess the microbiological quality of milk at different stages of the dairy value chain from farm to the factory in Bangladesh. A total of 438 raw milk samples (387 from primary producers, 32 from collectors, 15 from chilling plants, 4 from local restaurants) and 95 commercially processed milk samples were collected from northern part of Bangladesh. Almost 72% (n = 280) of samples at producer level and 100% from both collectors (n = 32) and chilling plants (n = 15) were contaminated with coliforms while 57% (n = 220) of samples from producers, 91% (n = 29) of samples from collectors and 100% (n = 15) from chilling plants were contaminated with fecal coliforms. Around 31% (n = 119) of samples from producers were positive for E. coli whereas >60% (n = 20) and 100% (n = 15) samples from collectors and chilling plants, respectively were positive for E. coli. One quarter of samples from collectors were positive for B. cereus and coagulase positive staphylococci and 33% (n = 5) of samples from chilling plants were positive for both of these microorganisms. In case of commercially processed milk, 77% (n = 46) and 37% (n = 22) of pasteurized milk samples had a high aerobic plate count (APC) (104 CFU/ml) and coliform count (>10 CFU/ml), respectively. None of the samples was positive for Shigella spp., Salmonella spp., and Campylobacter spp. Among 158 E. coli positive raw milk samples, 9% (n = 14) contained pathogenic E. coli, and enteroaggregative E. coli (EAEC) and Shiga-toxin producing E. coli (STEC) were found to be the predominant pathotypes. Of the 23 pathogenic E. coli identified from 14 samples based on their gene contents, >95% (n = 22) were resistant to at least one antibiotic and 13% (n = 3) of isolates were resistant to ≥3 classes of antibiotics. Several factors including the time of milking, hygiene practices of the producers, cow breed and amount of milk produced by the cow were found to be significantly associated with high APC of milk samples. In conclusion, both raw and commercially pasteurized milk are highly contaminated with fecal organisms. For intervention, more emphasis should be given at producer's level as microorganisms introduced to milk at this stage get the longest time for survival and multiplication.

Case report of a pustular dermatitis outbreak in sheep: Clinical and food safety considerations.

The objective of this report is to describe an outbreak of pustular dermatitis in a flock of about 200 sheep, its clinical evolution and food safety implications. The onset of the symptoms was sudden and the lesions spread very quickly from ewe to ewe, so that in about 3 days almost all of the lactating sheep were stricken. Pustules from 5 different animals, six milk samples, two cheese samples, teat cup samples from the milking machine and farmer’s hands were analysed. A pure culture of Staphylococcus aureus, producing staphylococcal enterotoxin (SE) C, was isolated from pustules. Milk and cheese showed a contamination by coagulase positive staphylococci <15 and 30 colony forming units respectively and the absence of SE. Farmer’s hands and teat cups samples resulted negative for coagulase positive staphylococci. Therapy with daily topical medicaments was prescribed and a prophylactic intervention was suggested by the administration of an autovaccine. The low level of milk and cheese contamination and the absence of SE in cheese supported the decision to not advise the farmer to recall cheese produced with milk from affected animals.

Contribution of natural milk culture to microbiota, safety and hygiene of raw milk cheese produced in alpine malga.

Processing of alpine milk in malga farms is carried out under conditions that can favor contamination by coliforms, coagulase-positive staphylococci, or pathogens such as Listeria monocytogenes. With the aim to improve the hygienic characteristics and safety of cheese produced in four malga farms the use of lyophilized Natural Milk Culture prepared with selected strains was tested.. Two cheesemaking tests were carried out in the same day always starting from the same milk: in the first case following the malga recipe that uses either Natural Whey Culture or without the addition of a starter, in the second one using a Natural Milk Culture. Cheesemaking were carried out in four malga farms located in the west area of Trentino region within the same week. For hygienic and safety evaluation, aerobic colony count, coagulase-positive staphylococci, Escherichia coli, staphylococcal toxins, Listeria monocytogenes, and Salmonella spp, pH and awwere determined in raw milk from evening and morning milking, curd in vat, curd after extraction and two months-ripened cheese. Pathogens or toxins, high values of coagulase- positive staphylococci and E. coli were not found in cheese samples. However, in the curd coagulase-positive staphylococci reached values almost of 5 Log CFU/g in the two malga without starter cultures. The use of Natural Milk Culture reduced E. coli counts. In addition, DNA was extracted from cheese samples and from Natural Milk Culture and the composition of the microbial community determined by Next Generation Sequencing method. The determination of cheese microbial communities demonstrated that the use of Natural Milk Culture exerted different effects in the different malga, in any case preserving bacterial biodiversity.

Development of resistance to antibiotics in bacteria Staphylococcus spp. Isolated from milk samples in the sheep breedings on east of Slovakia

During the last three years (2015 to 2017), the frequency of occurrence of bacteria Staphylococcus spp. were examined in total 3466 individual and 12 pool milk samples. Experiment was carried out in two herds of breed of sheep Improved Valaska in region of East Slovakia. Were isolated and taxonomically identified 15 species of the genus Staphylococcus spp. (n = 444). From the coagulase positive staphylococci (CPS), S. aureus was isolated during the reporting period, however, most often in the first year (45). The incidence of S. intermedius and S. hyicus has been irregular. From the coagulase negative staphylococci (CNS) (n = 288), were isolated S. epidermidis present in 37.5% (108), S. scheiferi 25.69% (74) and S. chromogenes 23.61% (68), while other species occurred only rarely. The bacteria S. aureus (n = 117) showed the highest resistance to novobiocine 14.5%, to erythromycin 12.8%, lincomycin 7.69% and also 7.69% to penicillin. In the framework of the CNS sensitivity we tested 108 strains of S. epidermidis, from which it was 11.1% resistant to novobiocine and 8.3% to erythromycin. Statistical comparison of the incidence of resistance to penicillin and novobiocine in S. aureus and S. epidermidis was performed using Chi square test. There was statistically significant dependence of tracked characters was confirmed on significance level α = 0.05. Also, the incidence of intermediate sensitivity of bacteria in the Staphylococcus spp., indicates the unfavourable development of resistance to the most commonly used antibiotics to treat the inflammation of the udder in sheep. It is therefore recommended to regularly check the resistance to antibiotics and often isolated bacteria CNS.

Microbiological, chemical-physical and sensory characteristics of Fabriano salami from pigs fed Oregano vulgaris extract.

This study aimed at evaluating the effect of Oregano vulgaris extract supplementation of heavy pig diet on the microbiological, chemical-physical and sensory characteristics of Fabriano salami. Fabriano salamis were produced processing meat derived from pigs belonging to two dietary groups of 16 pigs each: CTRL group fed a commercial pelleted feed, and OR group fed the CTRL diet integrated with 0.2% of oregano extract. Ten salamis per group were collected at 0, 7, 20 and 45 days of ripening and analysed for total viable count, enumeration of Enterobacteriaceae, Enterococcus spp, coagulase negative and positive staphylococci, Lactobacillus spp., Lactococcus spp., presence of Salmonella spp. and Listeria monocytogens, pH, water activity (aw) and colour (CIE L*a*b* colour system). At the end of the ripening (day 45) chemical composition (AOAC, 1990), total antioxidant capacity (ORACFL), thiobarbituric reactive substances (TBARS), total phenolic content (TPC) (Folin-Ciocalteu method) and consumer tests were performed. The integration of oregano extract in pig diets did not interfere with the microbial evolution, chemical composition, pH and aw. After 20 days of ripening the OR salami were redder then CTRL samples, which were also yellower at the end of ripening. Furthermore, the diet has significantly improved the oxidative status, the polyphenolic content and antioxidant power in OR salami. The consumers gave a higher score to OR salami in informed condition.

Hygienic-sanitary quality of Minas fresh cheese sold in the city of Botucatu, São Paulo

ABSTRACT: The Minas fresh cheese is a fresh and moist cheese and, therefore, has a short shelf-life. The use of raw milk as the main feedstock, the absence of ripening and the facility of contamination are factors that can compromise the product’s microbiological quality. The aim of this study was to describe the hygienic-sanitary quality of 50 Minas fresh cheeses marketed in Botucatu city, São Paulo, Brazil, close to their production date, and another 50 units from the same lot exactly on the expiration date, according to the Brazilian Sanitary Surveillance Agency (ANVISA). We also searched for enterotoxins genes in Staphylococcus aureus and its in vitro expression. In 36% of the first analyzed samples, the count of coliforms at 45ºC was above the limit and, as for the second analysis, 44%. Regarding coagulase positive staphylococci, 10 (20%) samples showed concentration above the permitted by law next to the production date and 14% on the expiration date. Salmonella was only observed in one sample analyzed near the date of production, while L. monocytogenes only in one sample analyzed on the expiration day. We isolated three enterotoxigenic strains of S. aureus that produced Staphylococcal Enterotoxin B (SEB) and Staphylococcal Enterotoxin C (SEC) in vitro, highlighting the importance of proper storage of this product due to its potential to cause intoxication. Overall, the quality of Minas fresh cheese is still unsatisfactory, leading to risks to consumers’ health.

Design, synthesis and antibacterial evaluation of a polycationic calix[4]arene derivative alone and in combination with antibiotics.

The growing antibiotic resistance phenomenon continues to stimulate the search for new compounds and strategies to combat bacterial infections. In this study, we designed and synthesized a new polycationic macrocyclic compound (2) bearing four N-methyldiethanol ammonium groups clustered and circularly organized by a calix[4]arene scaffold. The in vitro activity of compound 2, alone and in combination with known antibiotics (ofloxacin, chloramphenicol or tetracycline), was assessed against strains of Staphylococcus aureus (ATCC 6538 and methicillin-resistant isolate 15), S. epidermidis (ATCC 35984 and methicillin-resistant isolate 57), and Pseudomonas aeruginosa (ATCC 9027 and antibiotic-resistant isolate 1). Calix[4]arene derivative 2 showed significant antibacterial activity against ATCC and methicillin-resistant Gram positive Staphylococci, improved the stability of tetracycline in water, and in combination with antibiotics enhanced the antibiotic efficacy against Gram negative P. aeruginosa by an additive effect.

Prevalence of Staphylococcus aureus In Broiler Chickens with Special Reference to Beta-Lactam Resistance Genes in the Isolated Strains

The dramatic increase in the prevalence of antimicrobial-resistant Staphylococcus aureus (S. aureus) is receiving wide spread attention, due to multi-resistant strains, diminishing the usefulness of antibiotics in human and animal medicine and, thereby limiting therapeutic options. In this study, 250 samples of chicken swabs were collected from five different poultry farms (50 samples from each farm) within Upper Egypt area. 157 staphylococci strains were detected with an isolation rate of (62.8%). isolates of S. aureus were confirmed using standard microbiological methods. Eighty one (55.9%) were coagulase positive staphylococci, and 76(48.4%) were coagulase negative staphylococci, phenotypic prediction of β-lactam resistance among the 81 isolated coagulase positive staphylococci was declared using disk diffusion test against, cefoxitin and oxicillin which were used for detection of mecA mediated β-lactam resistance (methicillin resistance) while penicillin and amoxicillin/clavulinic acid (AMC) antibiotic discs were used to monitor blaZ mediated resistance. Out of 81 isolates ,all isolates were 100% resist to oxacillin and 93.8 % were resist to cefoxitin, while 90.1 % were resist to penicillin and 87.6% were resist to AMC. The antibiotic susceptibility results were judged by PCR, the mecA ,and blaZ genes were tested for the evaluation of the susceptibility of coagulase positive Staphylococci against oxacillin and s-lactams, the thirty one reprsentative coagulase positive staphylococci isolates confirmed that all the isolates were Staphylococci by successful amplification of the 228 bp PCR product of the Staphylococcal specific 16S rRNA gene. While , 20 isolates were confirmed to be S.aureus by successful amplification of 279 bp PCR product of the S.aureus specific thermonuclease gene .On using the same multiplex PCR assay, detection of blaZ and/or mecA genes were performed through successful amplification of 517 bp and /or 147 bp specific products, respectively. Out of the 31 reprsentative coagulase positive Staphylococci isolated from broiler chickens, 20 (64.5%) were mecA gene positive while 23 (74%) were β- blaZ gene positive. Also, 15 (48.3%) of the isolates carried both mecA and blaZ genes while only 3 isolates (9.6%) were negative for both genes. Concerning MIC of 12 representative coagulase positive staphylococci isolates against 12 selected antibiotics commonly used in poultry farms, 100% of isolates were resistant to streptomycin, spectinomycin ,ampicillin, Cefotax, Trimethoprim-sulphamethazole, gentamycin, and Methicillin with MIC >128, while 100% of isolates were sensitive to tylosin, lincomycine, enrofloxacin, ciprofloxacin and oxytetracyclin.

Isolation of Coagulase Positive Staphylococci from She-Camel Milk at Eastern Libya and Their Drug Susceptibility Patterns

Isolation of Coagulase Positive Staphylococci from She-Camel Milk at Eastern Libya and Their Drug Susceptibility Patterns

Interlaboratory Proficiency Testing trial on the Detection of Methicillin-resistant Staphylococcus aureus (MRSA) in food in Germany 2016

In the autumn 2016, the National Reference Laboratory for coagulase positive staphylococci (CPS) including Staphylococcus (S.) aureus (NRL-Staph) at the German Federal Institute for Risk Assessment has organized its first interlaboratory profiency testing (ILPT) trial for the detection of methicillin-resistant Staphylococcus aureus (MRSA) in food. The purpose of the ILPT was to assess the analytical competence of the official laboratories of the Federal German 'Lander' authorities. Moreover, it was the intention to gain an overview of the standard methods implemented in the participating laboratories for the purpose of MRSA detection in food. Five minced pork meat samples (1x blank, 2x not contaminated with MRSA but contaminated with methicillin-resistant S. sciuri, and 2x contaminated with MRSA) were sent in blind to each participant. In total, 19 laboratories participated to the ILPT, 18 from 12 Federal German 'Lander, and the NRL-Staph. Data sets from all 19 participating laboratories were included in the analysis. Overall, a specificity of 98.25% (56/57 true negative results), a sensitivity of 100% (38/38 true positive results), and an accuracy of 98.95% (94/95 true results) was achieved. All of the participants (19/19) used the screening method recommended for the detection of MRSA along the farm-to-fork food chain, which has been developed by the NRL-Staph. To conclude on the ILPT in general it is to state that almost all of the participating laboratories correctly identified MRSA contaminated samples demonstrating a very high analytical capacity in Germany. Moreover, the MRSA screening method developed by the NRL-Staph allows a reliable identification of MRSA contaminated samples.

Svojstva prevelog sira, tradicionalnog hrvatskog sušenog kiselinskog sira

Preveli cheese is Croatian artisanal dried acid-coagulated cheese. The aim of this paper was to study its physicochemical composition and microbiological properties, as well as physicochemical composition and hygienic quality of cheese milk. The results could be used for the improvement of Preveli cheese quality and for getting a mark of Protected Geographical Indication (PGI). The production of 35 batches of Preveli cheese was observed at 18 family farmsteads. Research showed that hygienic quality of milk was partially satisfying, which means that 51.42 % and 17.14 % of milk samples had total bacterial count and somatic cell counts above the threshold value (>300,00 and >400,000∙mL-1, respectively). According to the content of total solids, Preveli cheese belongs to the group of soft cheeses, while according to the content of fat in total solids it can be categorized as a fat cheese. Due to the non-standardized technological processes, mainly during skimming the milk fat, salting and drying, results of analysis showed notable variability in the physicochemical composition of the Preveli cheese and sour cream. The presence of yeast and moulds were detected in 22.86 % of cheese samples as well as coagulase positive staphylococci in 11.43 % of cheese samples, which indicated the need of improving the hygiene of the manufacturing processes.

Microbiological quality of fresh vegetable salads from the Novi Sad market

Increased consumption, big production units and very efficient delivery service networks of fresh vegetables and salads caused a higher number of foodborne illnesses in the last two decades all over the world. In this study 15 fresh vegetable salads from different marketplaces in Novi Sad were tested by reference microbiological methods (detection of Salmonella spp., enumeration of Listeria monocytogenes, mesophilic aerobic bacteria, yeasts and molds, sporogenic mesophilic aerobic bacteria, sporogenic sulfite-reducing bacteria, Bacillus cereus, Enterobacteriaceae, Escherichia coli and coagulase positive staphylococci). Salmonella spp. was found in one sample which, according to the safety criteria for such a product (if treated as ready-to-eat), was considered to be microbiologically unsafe. The number of Listeria monocytogenes in all tested samples was &lt;100 cfu/g, which is a satisfactory result according to the safety criteria. E. coli was detected in only one sample, and the number of Enterobacteriaceae was in the range from 4.4 to 6.9 log CFU/g. The isolated Enterobacteriaceae strains were identified as Enterobacter cloacae, Klebsiella pneumoniae ssp. pneumoniae and Citrobacter spp.

Avaliação microbiológica de queijo de coalho comercializado na feira livre de Sousa - Paraíba

&lt;p class="Default"&gt;For many years the curd cheese has stood out on the table of Brazilian consumers, especially in the Northeast due to its high nutritional value and its good taste and because of that it has been used in numerous dishes of the Northeastern cuisine. The aim of this study was to evaluate the microbiological quality of the curd cheese sold at a market garden in the city of Sousa-PB. Twenty curd cheese samples were collected every week during the month of October 2015, in five sales areas at a market garden in the city. Samples were analyzed at the Microbiological Analysis of Foods Laboratory of the Agroindustry sector at the Federal Institute of Education, Science and Technology of Paraíba, Campus Sousa, having as reference the Resolution of the Collegiate Board (RDC) n ° 12 of the National Sanitary Surveillance Agency. According to the results, the values obtained for total coliforms were considered high in almost all the samples. Regarding coliform, seven out of twenty samples (35%) were above the threshold count allowed by Brazilian law. As for the pathogenic to 65% of the samples presented coagulase positive Staphylococci counts and in 40% the growth of Salmonella sp,it was confirmed. Based on the results obtained,it can be said that these products are being manufactured without the adoption of Good Manufacturing Practices, which a condition that compromises the quality of the product and puts the health of consumers at risk&lt;/p&gt;

Food-Borne Outbreak Investigation and Molecular Typing: High Diversity of Staphylococcus aureus Strains and Importance of Toxin Detection.

Staphylococcus aureus is an important aetiological agent of food intoxications in the European Union as it can cause gastro-enteritis through the production of various staphylococcal enterotoxins (SEs) in foods. Reported enterotoxin dose levels causing food-borne illness are scarce and varying. Three food poisoning outbreaks due to enterotoxin-producing S. aureus strains which occurred in 2013 in Belgium are described. The outbreaks occurred in an elderly home, at a barbecue event and in a kindergarten and involved 28, 18, and six cases, respectively. Various food leftovers contained coagulase positive staphylococci (CPS). Low levels of staphylococcal enterotoxins ranging between 0.015 ng/g and 0.019 ng/g for enterotoxin A (SEA), and corresponding to 0.132 ng/g for SEC were quantified in the food leftovers for two of the reported outbreaks. Molecular typing of human and food isolates using pulsed-field gel electrophoresis (PFGE) and enterotoxin gene typing, confirmed the link between patients and the suspected foodstuffs. This also demonstrated the high diversity of CPS isolates both in the cases and in healthy persons carrying enterotoxin genes encoding emetic SEs for which no detection methods currently exist. For one outbreak, the investigation pointed out to the food handler who transmitted the outbreak strain to the food. Tools to improve staphylococcal food poisoning (SFP) investigations are presented.

Enterotoxin production and antimicrobial susceptibility in Staphylococci isolated from traditional raw milk cheeses in Serbia

ABSTRACTThis study was undertaken to determine the prevalence of coagulase positive staphylococci (CPS) by examining a total of 71 raw milk cheeses. Additionally, enterotoxigenicity, antimicrobial susceptibility and the presence of mecA and mecC genes in the staphylococcal isolates were investigated. The isolation and enumeration procedure of CPS followed the International Organization for Standardization (ISO) standard. The presumptive staphylococci were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) using the VITEK MS system. VIDAS® Staph enterotoxin II assay was used for the detection of classical enterotoxins. Antimicrobial susceptibility testing (AST) was accomplished performing the disk diffusion method. All suspected methicillin resistant staphylococci were investigated for the presence of mecA and mecC genes by PCR assay. A high prevalence (87.32%) of CPS was detected in the cheeses at contamination levels up to 5.58 log CFU g−1. Among 47 staphylococcal isolates screened for enterotoxin production, only one isolate, identified as S. hyicus, was confirmed as being enterotoxigenic. Resistance to penicillin (63.70%) was the most common resistance among the tested Staphylococcus aureus isolates. The dominant phenotypic resistance patterns in coagulase negative staphylococci (CNS) were resistance to ofloxacin and fusidic acid. All CNS isolates were susceptible to the clinically important antibiotics clindamycin, chloramphenicol, gentamicin, linezolid, rifampicin and trimethoprim-sulfamethoxazole. The mecA and mecC genes were not detected. To the best of our knowledge, this is the first study concerning evaluation of the presence of methicillin resistant staphylococci (MRS) in dairy products in Serbia.

QUALIDADE MICROBIOLÓGICA DE QUEIJO MINAS FRESCAL COMERCIALIZADO NA ZONA DA MATA MINEIRA

Este trabalho objetivou avaliar a qualidade microbiológica do queijo Minasfrescal comercializado na Zona da Mata Mineira. As amostras foram coletadas em seis municípios: Juiz de Fora (33), Cataguases (7), Itamarati de Minas (4), Belmiro Braga (2), Bicas (2) e Rio Pomba (2), totalizando 50 marcas, sendo 43 de produção industrial e sete informais. As análises de pH, atividade de água (Aw), coliformes a35 ºC e a 45 ºC, Escherichia coli, estafilococos coagulase positiva, Staphylococcus aureus, Listeria monocytogenes e Salmonella sp. foram realizadas entre outubro de 2015 e janeiro de 2016. Os valores de pH variaram entre 4,98 a 7,14 e a Aw entre 0,989 a 0,904. Todas as amostras, independente da origem, apresentaram coliformesa 35 ºC, com valores variando de 1,5 x 101 a 1,1 x 106 NMP/g. Dentre as amostras, 20 (40%) apresentaram Número Mais Provável acima do limite máximo estabelecido pela legislação para coliformes a 45 ºC, sendo a média de 1,2 x 105 NMP/g. A presença de E. coli foi confirmada em 16 amostras (32%). As contagens de estafilococos coagulase positiva também foram acima do limite aceito em 16 (32%) amostras e10 (20%) continham S. aureus. Não foi constatada presença de L. monocytogenes, entretanto, Salmonella sp. foi confirmada em 20 amostras (40%). Constatou-se que, apenas 11 amostras (22%), estavam em conformidade com a legislação brasileira. Portanto, o queijo Minas frescal comercializado na região apresentou baixa qualidade microbiológica, sugerindo deficiências no processamento, transporte, armazenamento e/ou comercialização e perigo à saúde humana

English

Meat is regarded as one of the main sources of food-borne diseases; its evaluation can constitute a valuable source of information that can be used in the design of collective prophylaxis programs in public health. In order to assess the level of contamination of certain meat products by coagulase-positive staphylococci and the influence of the storage temperature of these products, we conducted a study in three types of trade in the region of Algiers (Algeria). In total, 25 samples divided between meat products from red meat (minced meat, Merguez) and white meat (turkey, chicken) were taken at three different sales outlets (covered market, supermarkets and independent butchers), for bacteriological analysis. The mean of coagulase positive staphylococci were 1.60 &plusmn; 0.33 log10 cfu/g for minced meat, 2.02 &plusmn; 0.46 log10 cfu/g for Merguez, 2.02 &plusmn; 0.47 log10 cfu/g for turkey and 1.63 &plusmn; 0.21 log10 cfu/g for chicken. In addition, the descriptive analysis of the storage temperature data for these meat products revealed that, these temperatures have low correlations with variations in bacterial levels for minced meat, Merguez and turkey (minced). These results reflected insufficient hygienic conditions in the preparation, preservation and sale of these meat products. Thus, the consumption of these products can present a real health risk to public health. &nbsp; Key words: Algeria, coagulase positive staphylococci, contamination, meat products, storage temperature.