[Colonization by Staphylococcus aureus among the nursing staff of a teaching hospital in Pernambuco]

Nasal colonization with Staphylococcus aureus in nursing students: ground for monitoring

Objective:

to monitor bacterial strains of Staphylococcus aureus that are resistant or not to oxacillin in nursing undergraduate students, with an emphasis on the process of colonization.

Method:

cross-sectional prevalence study carried out with 138 nursing students. The biological samples of the nasal cavity were collected in June 2015, by means of sterile swabs, which were subsequently submitted to confirmatory tests of catalase and coagulase. Isolated Staphylococcus aureus had their sensitivity profile determined by means of the Kirby Bauer method. Descriptive, univariate and bivariate analyses were performed.

Results:

the prevalence of Staphylococcus aureus was 21.7. Regarding the resistance profile, 24.1% of strains were resistant to oxacillin, with ampicillin being the antimicrobial with the greatest resistance (82.8%).

Conclusion:

the nasal cavity is an important bacterial flora of S. aureus in nursing students. The profile of isolated strains highlights the increase of Staphylococcus aureus resistance to antimicrobials such as oxacillin.

STAPHYLOCOCCUS AUREUS IN NURSING PROFESSIONALS AND THE MICROORGANISM’S SUSCEPTIBILITY PROFILE TO ANTIMICROBIALS

ABSTRACT Objective: to identify the carrier’s state and the susceptibility profile of Staphylococcus aureus isolated from saliva and nasal secretion of nursing professionals to antibiotics. Method: cross-sectional study that used saliva and nasal secretion samples of 100 nursing professionals who provide care for patients with HIV/Aids. Results: forty-three percent of the participants presented positive saliva or nasal secretion samples for Staphylococcus aureus. Of the 74 nasal secretion samples with Staphylococcus aureus, 14.9% presented oxacillin resistance; 91.9% presented penicillin resistance; 44.6% presented erythromycin resistance, and 41.9% presented clindamycin resistance. Of the 12 positive saliva samples, 16.7% presented oxacillin resistance; 100.0% presented penicillin resistance; 33.4% presented erythromycin resistance, and 25.0% presented clindamycin resistance. Conclusion: nursing professionals, once aware of their carrier state of multi-resistant microorganisms, will supervise their care practices and more efficiently adopt measures for prevention and control of the epidemiological chain of these bacteria in their work environment.

Nasal carriage of resistant Staphylococcus aureus in a medical student community

Staphylococcus aureus can cause a variety of infections due to its high transmissibility, high pathogenic potential and resistance to multiple drugs, factors that contribute to the relevance of infections in healthcare services. The aim of this study was to document phenotypic and genotypic resistance factors of Staphylococcus aureus strains, isolated from nasal mucosa of medical students. A nasal swab was collected from the nares (nostrils) of 222 medical students. After collection, the samples were submitted to isolation and identification procedures. From 204 valid samples, 20.6% (42 samples) were positive for S. aureus. For the assessment of phenotypic resistance by disk-diffusion technique, from 42 samples, 95.2% showed resistance to erythromycin, 42.8% to clindamycin, 16.6% to cephoxitin and 9.5% to oxacillin. The D test showed that 26.2% of samples were resistant to macrolides, lincosamides and streptogramin B. A PCR assay allowed for the evaluation of a genotypic resistance profile, in which 16.6% of the samples were positive for the mecA gene, 35.7% positive for the ermC gene or ermA gene and 28.5% were positive for both genes. These results demonstrate that medical students can enter the healthcare service previously colonized by multidrug resistant strains and become potential spreaders in the hospital environment.

Enterobacteriaceae isolates from the oral cavity of workers in a Brazilian oncology hospital

The evaluation of workers as potential reservoirs and disseminators of pathogenic bacteria has been described as a strategy for the prevention and control of healthcare-associated infections (HAIs). The aim of this study was to evaluate the presence of Enterobacteriaceae in the oral cavity of workers at an oncology hospital in the Midwest region of Brazil, as well as to characterize the phenotypic profile of the isolates. Saliva samples of 294 workers from the hospital's healthcare and support teams were collected. Microbiological procedures were performed according to standard techniques. Among the participants, 55 (18.7%) were colonized by Enterobacteriaceae in the oral cavity. A total of 64 bacteria were isolated, including potentially pathogenic species. The most prevalent species was Enterobacter gergoviae (17.2%). The highest rates of resistance were observed for β-lactams, and 48.4% of the isolates were considered multiresistant. Regarding the enterobacteria isolated, the production of ESBL and KPC was negative. Nevertheless, among the 43 isolates of the CESP group, 51.2% were considered AmpC β-lactamase producers by induction, and 48.8% were hyper-producing mutants. The significant prevalence of carriers of Enterobacteriaceae and the phenotypic profile of the isolates represents a concern, especially due to the multiresistance and production of AmpC β-lactamases.