Prevalence Of Staph Research Articles

Correlation Between Methicillin Resistance and Enterotoxins Production in Staphylococcus aureus Isolated from some Salted Fish

The goal of this research was to find out Staphylococcus aureus incidence in sixty samples of some salted fish (salted sardine, Feseikh, and Molouha) obtained from random places in Kafrelsheikh Governorate as well as the prevalence rate of MRSA (mecA gene) in relation to enterotoxin production (Sea, Seb, Sec, Sed) by using PCR techniques. Furthermore, studying the relationship between salt content and the occurrence of Staph. aureus. Overall, coagulase positive Staph. aureus was identified in 30, 20, and 10% of salted sardine, feseikh, and molouha samples, with mean values of 3.05± 1.73, 3.45± 2.14 and 2.64± 1.39 (log 10) cfu/g, respectively. The mec A gene was identified by PCR in all coagulase positive Staph. aureus isolates (12 isolate), otherwise Sea gene wasn't detected in any of the positive MRSA isolates, Seb and Sec genes were found in 33.33% (each) of MRSA strains from salted sardine samples and 25% (each) of MRSA isolates from feseikh samples, and only one isolate (50%) from the molouha samples contained Sed gene. The salt content of the examined molouha samples were noticeably different (P< 0.05) from the other examined samples, whereas, between salted sardine and feseikh samples there was no statistically significant difference (P< 0.05), and inverse relationship was found between salt content and the prevalence of Staph. aureus. The presence of MRSA with staphylococcal enterotoxigenic genes in salted fish could be regarded as providing a health risk to consumers. Therefore, a significant effort should be made to maintain hygienic conditions in the processing, preparation, and handling of fish products to keep contamination to a minimum.

Phenotypic and Genotypic Detection of Virulence Factors of Staphylococcus Aureus Isolated from Meat and Meat Products

A total of 250 random samples of meat and meat products 50 of each meat, luncheon, burger, minced meat and sausagesamples were collected from different butchers in Port-Said Governorate. All samples were subjected to bacteriological examination for isolation and identification of Staph. aureus.The results revealed that the Staph. aureus wasisolated in a percentage of 55 (22%). The prevalence of Staph. aureus isolates in the examined meat, luncheon, burger, minced meat and sausage samples were 14%, 20%, 30% ,34% and 12%, respectively. Coagulase positive Staph. aureus (CPS) was isolated in percentage of 33(60%) from the examined meat, luncheon, burger, minced meat and sausage samples. CPS isolates could be detected in meat, luncheon, burger, minced meat and sausage samples with a percentage of 57.15%, 600%, 60%, 58.82% and 66.66%, respectively. The antibiotic resistance of coagulase positive Staph. aureus using 14 antibacterial drugs by disk diffusion method were resistant to Cephalexin, Chloramphenicol, Cprofloxacin, Clindamycin, Erythromycin, Vancomycin, Trimethoprim + Sulphamethoxazole, Gentamicin and Streptomycin and found with a percentage of 87.88%, 84.85%, 75.76%, 72.73%, 72.73%, 69.70%, 63.64%, 60.60% and 57.58% respectively. The conventional PCR assays were developed with specific primers for the detection of different types of virulence genes in 20 strong CPS strains as protein A in Staphyloccocus (spa), coagulase (coa), haemolysin (hlg) and intacellular adhesion (icaA) while multiplex PCR assay were developed to detect of two types of Staphylococcal enterotoxins (sea and seb). The PCR amplification of the spa gene was 3/4, 2/4, 1/4, 1/4 and 2/4 coagulase positive Staph. aureus at 226 bp from meat, luncheon, burger, minced meat and sausage respectively, While the all 20 confirmed coagulase positive Staph. aureus was examined for coagulase (coa) gene using specific gene were positive at 360 bp. 0/4, 2/4, 0/4, 0/4 and 2/4. Identified coagulase positive Staph. aureus isolates were amplified the diagnostic DNA band successfully at 937 bp for hlg gene from meat, luncheon, burger, minced meat and sausage were 4/4, 3/4, 3/4, 3/4 and 2/4 respectively. Amplification of the icaA gene was 4/4, 3/4, 3/4, 3/4 and 2/4 at 1315 bp from meat, luncheon, burger, minced meat and sausage respectively. Multiplex PCR could successfully amplify the diagnostic DNA bands of 102bp and 164 bp, of genes for staphylococcal enterotoxins sea and seb, respectively. The results showed that 1/4, 1/4, 2/4, 1/4 and 0/4 isolates of Staph. aureus was positive for seb at 164 bp from meat, luncheon, burger, minced meat and sausage respectively. While none of the samples were positive for sea. The public health hazards of this microorganism, as well as improve quality status of meat and meat products were discussed.

Relationships among superantigen toxin gene profiles, genotypes, and pathogenic characteristics of Staphylococcus aureus isolates from bovine mastitis

Staphylococcus aureus is one of the major etiological agents of bovine mastitis, harboring a wide variety of staphylococcal superantigen (SAg) toxin genes. The SAg toxin genes are reported to be closely associated with the pathogenicity of the Staph. aureus causing the bovine mastitis. This study was conducted to investigate SAg toxin gene profiles and to assess the relationships among SAg toxin genes, genotypes of Staph. aureus, and their pathogenic properties. A total of 327 quarter milk samples were collected from bovine mastitis cases for isolation and identification of pathogens. In total, 35 isolates were identified as Staph. aureus, and the prevalence of Staph. aureus in milk samples was 13.6% (35/256). Polymerase chain reaction (PCR) and randomly amplified polymorphic DNA (RAPD) assays were used to detect the SAg toxin genes and to genotype Staph. aureus strains isolated from milk samples of bovine mastitis in 10 dairy herds located in Ningxia, China, respectively. The results showed that among the Staph. aureus isolates (n = 35), 71.4% (n = 25) of isolates carried at least one SAg toxin gene. In total, 18 SAg genes and 21 different gene combination patterns were detected among these isolates. The most common SAg genes in Staph. aureus isolates were sei, sen, and seu (44.0% each), followed by seo, tst, and etB (28.0% each), etA (24.0%), sem and sep (16.0% each), seb, sec, sed, and sek (12.0% each), and sea and seh genes (8.0% each); the seg, sej, and ser genes were present in 4.0% of the isolates. Three gene combinations were found to be related to mobile genetic elements that carried 2 or more genes. The egc-cluster of the seg-sei-sem-sen-seo genes, located on the pathogenicity island Type I υSaβ, was detected in 16% of isolates. Interestingly, we observed 6 RAPD genotypes (I to VI) in Staph. aureus isolates, and 2 of these genotypes were strongly associated with the severity of bovine mastitis; there was a close relationship between the RAPD genotypes and SAg genes. Isolates of RAPD type III were more frequently associated with clinical and subclinical mastitis, whereas strains of type VI were mostly related to subclinical mastitis. In addition, SAg genes were related to severity of bovine mastitis. We conclude that an obvious relationship exists among RAPD genotypes, SAg toxin genes, and severity of bovine mastitis.

DETECTION OF MECA GENE IN METHICILLIN-RESISTANCE STAPHYLOCOCCUS AUREUS (MRSA) STRAINS ISOLATED FROM BEEF MEAT USING POLYMERASE CHAIN REACTION

A total of 60 random samples of meat were collected from different butchers shops at Port- Said city and subjected to bacteriological examination. The prevalence of Staph. aureus coagulase positive was 10 (16. 6%). The coagulase positiveStaph. aureus isolates were tested for their susceptibility to methicillin/ Oxaciillin. 6(60%) of the isolates were resistant to methicillin/ Oxaciillin. Multidrug resistance of MRSA strains was observed. The maximum resistance was observed against Ampicillin and Chloramphenicol (100%) while the least resistance was observed against Streptomycin (66.6%) followed by Gentamicin and Trimethoprim + Sulphamethoxazole (33.3%) and Erythromycin (16.6%). The isolates were analyzed for the presence of the genes encoding resistance to methicillin (mecA) by using Polymerase chain reaction (PCR) which is a powerful and a rapid procedure for the detection of mecA gene in methicllin-resistance (MRSA) strains. Only 3 out of 6 isolates were found to carry the mecA gene amplified at 310 bp. The Staph. aureus found in meat directly affect the human health and can cause a public illness if the meat is used in the food industry. Examination of meat using convetional PCR is a useful technique for detection of mecA gene inMethicillin-resistanceStaph. aureus (MRSA).

OCCURRENCE AND ANTIBIOTIC SUSCEPTIBILITY PRO-FILES OF STAPHYLOCOCCUS AUREUS IN SPUTUM OF TB PATIENTS

Abstract Patients with tuberculosis are easily exposed to other infections especially of staph aureus due to lack of immunity. Aims and Objectives: Study was designed to identify the presence of staph in sputum of patients as this micro-organism may interfere with the treatment of patients. Study also tried to find out the most suitable antibiotic effective against staph aureus. Methodology: Sputum samples of 50 patients with tuberculosis were taken for the presence of staph aur-eus from Feb 2014 - May 2014. Patients were taken from out Door Department of Chest Clinic of Sir Gan-ga Ram Hospital. Patients provided consent prior to assessment. Identification of S. aureus was confirmed by a positive catalase and coagulase test. Susceptibili-ties were carried out by standard disk diffusion method using antibiotic multidisc containing augmentin (30 ug), gentamicin (10 ug) and ciprofloxacin (5 ug). At the end of incubation, the diameters of the zones of in-hibition were measured by ruler. Results: Mean age of male patients was 32.22 and of female was 36.41. BMI of male was 19.66 kg/m 2 and of female patient was 17.5 Kg/m 2 . 100% male and female patients showed the presence of catalase posi-tive staph aureus . Sensitivity of ciprofloxacin against the strains of Staph aureus was 27.7% in male and 41.6% in female patients. Sensitivity of gentamicin against the strains of Staph aureus was 50% in male and 25% in female patients. Among three antibiotics augmentin showed highest resistance against the staph aureus i.e. 78% in case of male and 66% in female patients. Conclusion: A high prevalence of staph aureus in sputum of TB patients is alarming which may be due to polluted environment and week immunity. Effective antibiotic against the strains of staph aureus is genta-micin in male and ciprofloxacin in female sputum sample. Further studies are needed to confirm the high carrier rate as well as to evaluate the impact of staph aureus on morbidity and mortality among large num-ber both sexes of TB patients. Key Words: Sputum, Staph aureus, tuberculosis.

Clinical outcomes and molecular genotyping of Staphylococcus aureus isolated from milk samples of dairy primiparous Mediterranean buffaloes (Bubalus bubalis)

Staphylococcus aureus is one of the most important pathogens causing mastitis in dairy cows and in Mediterranean buffaloes. Genotype B (GTB) is contagious in dairy cows and may occur in up to 87% of cows of a dairy herd. It was the aim of this study to evaluate genotypes present, clinical outcomes, and prevalence of Staph. aureus in milk samples of primiparous Mediterranean dairy buffaloes. Two hundred composite milk samples originating from 40 primiparous buffaloes were collected from May to June 2012, at d 10, 30, 60, 90, and 150 d in milk (DIM) to perform somatic cell counts and bacteriological cultures. Daily milk yields were recorded. Before parturition until 40 to 50 DIM, all primiparous animals were housed separated from the pluriparous animals. Milking was performed in the same milking parlor, but the primiparous animals were milked first. After 50 DIM, the primiparous were mixed with the pluriparous animals, including the milking procedure. Individual quarter samples were collected from each animal, and aliquots of 1mL were mixed and used for molecular identification and genotyping of Staph. aureus. The identification of Staph. aureus was performed verifying the presence of nuc gene by nuc gene PCR. All the nuc-positive isolates were subjected to genotype analysis by means of PCR amplification of the 16S-23S rRNA intergenic spacer region and analyzed by a miniaturized electrophoresis system. Of all 200 composite samples, 41 (20.5%) were positive for Staph. aureus, and no genotype other than GTB was identified. The prevalence of samples positive for Staph. aureus was 0% at 10 DIM and increased to a maximum of 22/40 (55%) at 90 DIM. During the period of interest, 14 buffaloes tested positive for Staph. aureus once, 6 were positive twice, and 5 were positive 3 times, whereas 15 animals were negative at every sampling. At 90 and 150 DIM, 7 (17.5%) and 3 buffaloes (7.5%), respectively, showed clinical mastitis (CM), and only 1 (2.5%) showed CM at both samplings. At 60, 90, and 150 DIM, 1 buffalo was found with subclinical mastitis at each sampling. At 30, 60, 90, and 150 DIM, 2.5 (1/40), 22.5 (9/40), 35 (14/40), and 10% (4/40) were considered affected by intramammary infection, respectively. Buffaloes with CM caused by Staph. aureus had statistically significantly higher mean somatic cell count values (6.06±0.29, Log10 cells/mL ± standard deviation) and statistically significantly lower mean daily milk yields (7.15±1.49, liters/animal per day) than healthy animals (4.69±0.23 and 13.87±2.64, respectively), buffaloes with IMI (4.82±0.23 and 11.16±1.80, respectively), or with subclinical mastitis (5.47±0.10 and 10.33±0.68, respectively). Based on our knowledge, this is the first time that Staph. aureus GTB has been identified in milk samples of dairy Mediterranean buffaloes.

Genotype-specific risk factors for Staphylococcus aureus in Swiss dairy herds with an elevated yield-corrected herd somatic cell count

Bovine mastitis is a frequent problem in Swiss dairy herds. One of the main pathogens causing significant economic loss is Staphylococcus aureus. Various Staph. aureus genotypes with different biological properties have been described. Genotype B (GTB) of Staph. aureus was identified as the most contagious and one of the most prevalent strains in Switzerland. The aim of this study was to identify risk factors associated with the herd-level presence of Staph. aureus GTB and Staph. aureus non-GTB in Swiss dairy herds with an elevated yield-corrected herd somatic cell count (YCHSCC). One hundred dairy herds with a mean YCHSCC between 200,000 and 300,000cells/mL in 2010 were recruited and each farm was visited once during milking. A standardized protocol investigating demography, mastitis management, cow husbandry, milking system, and milking routine was completed during the visit. A bulk tank milk (BTM) sample was analyzed by real-time PCR for the presence of Staph. aureus GTB to classify the herds into 2 groups: Staph. aureus GTB-positive and Staph. aureus GTB-negative. Moreover, quarter milk samples were aseptically collected for bacteriological culture from cows with a somatic cell count ≥150,000cells/mL on the last test-day before the visit. The culture results allowed us to allocate the Staph. aureus GTB-negative farms to Staph. aureus non-GTB and Staph. aureus-free groups. Multivariable multinomial logistic regression models were built to identify risk factors associated with the herd-level presence of Staph. aureus GTB and Staph. aureus non-GTB. The prevalence of Staph. aureus GTB herds was 16% (n=16), whereas that of Staph. aureus non-GTB herds was 38% (n=38). Herds that sent lactating cows to seasonal communal pastures had significantly higher odds of being infected with Staph. aureus GTB (odds ratio: 10.2, 95% CI: 1.9–56.6), compared with herds without communal pasturing. Herds that purchased heifers had significantly higher odds of being infected with Staph. aureus GTB (rather than Staph. aureus non-GTB) compared with herds without purchase of heifers. Furthermore, herds that did not use udder ointment as supportive therapy for acute mastitis had significantly higher odds of being infected with Staph. aureus GTB (odds ratio: 8.5, 95% CI: 1.6–58.4) or Staph. aureus non-GTB (odds ratio: 6.1, 95% CI: 1.3–27.8) than herds that used udder ointment occasionally or regularly. Herds in which the milker performed unrelated activities during milking had significantly higher odds of being infected with Staph. aureus GTB (rather than Staph. aureus non-GTB) compared with herds in which the milker did not perform unrelated activities at milking. Awareness of 4 potential risk factors identified in this study guides implementation of intervention strategies to improve udder health in both Staph. aureus GTB and Staph. aureus non-GTB herds.

Antimicrobial resistance and toxin gene profiles of Staphylococcus aureus strains from Holstein milk

Isolation of Staphylococcus aureus (Staph. aureus) from Holstein milk samples with mastitis and nonmastitis was conducted to estimate its prevalence, antimicrobial resistance and toxin genes. A total of 353 milk samples were collected from three Chinese Holstein herds. Fifty-three Staph. aureus isolates collected from 29 Staph. aureus-positive samples were characterized via antimicrobial susceptibility, toxin genes and Pulsed-field Gel Electrophoresis (PFGE) profiles. The prevalence of Staph. aureus was 4·0-9·5% in mastitic and 7·3-11·5% in nonmastitic samples in the analysed herds. Approximately 61·0% of Staph. aureus strains isolated from mastitis cows were resistant to ≥10 antimicrobials compared with 0% of isolates with nonmastitis. The most frequently observed super antigenic toxin gene was pvl (41·5%) followed by seh + pvl (13·2%). We did not find mecA-positive methicillin-resistant Staph. aureus (MRSA) strains, while mecA-negative MRSA strains were identified in the three herds. PFGE results suggested potential transmission of Staph. aureus strains in different farms. These results open new insights into Staph. aureus transmission and antimicrobial resistance of Holstein dairy cows and into developing strategies for udder health improvement of dairy cattle. Significantly higher levels of antibiotic resistance of Staphylococcus aureus strains were detected in the lactating Holstein milk with clinical mastitis compared with that without clinical mastitis. PFGE results suggest potential transmission of Staph. aureus strains in different dairy farms. The results imply that the dairy farms need to select effective antibiotics in the treatment of Staph. aureus-infected cows and prevent the transmission of Staph. aureus strains from one herd to another.

Management practices associated with the bulk-milk prevalence of Staphylococcus aureus in Canadian dairy farms

When designing mastitis-prevention and control programs, it is important to know the level of adoption of mastitis-prevention management practices and control programs and the herd-level prevalence of contagious mastitis pathogens. Our objectives were to estimate: (1) adoption of recommended mastitis-preventive management on Canadian dairy farms; (2) herd-level prevalence of contagious mastitis pathogens on Canadian dairy farms; and (3) associations of certain management practices with the isolation of Staphylococcus aureus from the bulk tank milk from Canadian dairy farms. In total, 226 farms participating in dairy herd improvement milk recording were randomly selected. All participating farms in British Columbia had free-stall barns and 85% of farms in Québec had tie-stall barns. Post-milking teat disinfection was practised on 96% of the farms and 72% had implemented blanket dry-cow treatment. Weighted and province-stratified prevalence of Streptococcus agalactiae and Staph. aureus in bulk tank milk was 4% (95% confidence interval: 0–12%) and 74% (95% confidence interval: 61–86%), respectively. Highest Staph. aureus prevalence was found in Nova Scotia (91%) and lowest prevalence in British Columbia (38%). No Mycoplasma spp. were isolated, but detection of Mycoplasma spp. could have been hampered by the frozen shipment and storage of the milk samples. Management practices associated with a lower probability of isolating Staph. aureus were blanket dry-cow treatment and believing that a nutritionist is important in mastitis data review. Having the milking equipment checked by an independent technician at least once a year and rubber mats or mattresses in the free-stall barns were associated with an increased probability of isolating Staph. aureus from the bulk tank. Most of Canadian dairy farms adopted important mastitis-prevention practices, such as post-milking teat disinfection and drying off all cows with antibiotics; however, improvements can still be made. A few management practices were associated with the prevalence of Staph. aureus in bulk tank milk, such as dry-cow treatment and barn type for the lactating cows. Further work has to be carried out to investigate to what extent the associations are causal.

Identification of potential sources of Staphylococcus aureus in herds with mastitis problems

Staphylococcus aureus is a common udder pathogen of dairy cows that often causes herd problems. Various mastitis control programs have been used to combat the problem but have not always been efficient in preventing new Staph. aureus infections, indicating the presence of possible sources of infection other than those traditionally considered. Therefore, the aim of the study was to identify potential sources of infection relevant for Staph. aureus mastitis within 5 dairy herds with udder health problems caused by Staph. aureus. Samples were collected from milk of lactating cows, from body sites, and from the environment of lactating cows, dry cows, late pregnant heifers, young heifers 4 to 12 mo old, and heifer calves 0 to 3 mo old. Isolates of Staph. aureus were identified and compared using pulsed-field gel electrophoresis. Four to 7 unique Staph. aureus pulsotypes were found within each herd, with one strain predominating in milk in each herd. The milk pulsotypes were also frequently isolated in body samples, especially on hock skin, and in the immediate environment of lactating cows, and were sometimes found in other animal groups, especially in dry cows and heifer calves 0 to 3 mo old. The prevalence of Staph. aureus in milk and other types of samples varied markedly between herds. Staphylococcus aureus isolates with genotypes indistinguishable from those found in milk also dominated in extra-mammary sites within the dairy herds studied, and hock skin was identified as an important reservoir of Staph. aureus. The results contribute new knowledge necessary to improve strategies for udder health control in herds.

Staphylococcus aureusstrains in primiparous and multiparous cows in six herds with a high prevalence ofStaph. aureusintramammary infections

The proportion of different strains of Staphylococcus aureus was tested in four groups of lactating dairy cows in six herds with a high overall prevalence of Staph. aureus using random amplified polymorphic DNA PCR. Group 1 included primiparous cows in early lactation (<50 days in milk, DIM). Group 2 consisted of primiparous cows in late lactation (>250 days in milk). Groups 3 and 4 were multiparous cows in the respective stages of lactation. Eight cows from each group on each farm were tested. Overall quarter prevalence of Staph. aureus ranged from 23.4 to 32.0% in the herds. Of the 130 isolates included in the analysis 86.9% were high prevalence strains (more than three isolates per herd), while 13.1% were strains that were only identified in one or two samples. Low prevalence strains were found in all six herds. The proportion of low prevalence strains was higher in multiparous than in primiparous cows (odds ratio, OR 4.4, 1.2-16.6). It is concluded that low prevalence Staph. aureus strains are common even in herds with a high prevalence of Staph. aureus and that their frequency is lower in primiparous cows than in older cows.

Bacterial colonization of infants raised in incubators and under radiant heaters.

To assess the effect of open radiant heaters on bacterial colonization of neonates, 24 infants were raised under radiant heaters and 34 in standard incubators. Cultures of the nose, groin, and umbilicus were taken daily for the first 3 days of life. For infants raised in incubators, colonization rates with Staph. aureus ranged up to 47%. Among infants raised under radiant heaters (8 of whom had topical antibiotics applied to the umbilicus), only one was colonized with this organism. Even if the 8 treated infants were excluded, the prevalence of Staph. aureus was significantly greater at the umbilicus and groin in infants raised in incubators.