Prevalence and antimicrobial susceptibility profiles of Staphylococcus aureus nasal carriage among pre-clinical and clinical medical students in a Tanzanian University

Introduction: To determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) nasal carriage and detection of S. aureus leukotoxins among medical students of Universiti Teknologi MARA. Methods: Both sides of the anterior nares of 136 volunteers, comprising 68 preclinical and 68 clinical medical students, were swabbed and immediately cultured onto mannitol salt agar for growth of S. aureus. Standard microbiological techniques were conducted to identify and confirm the S. aureus colonies and susceptibility test against oxacillin were conducted by using Kirby-Bauer method to determine their resistance to methicillin. Polymerase chain reaction was performed for detection of leukotoxins, i.e., Panton-Valentine Leukocidin (PVL) and -haemolysin genes. Results: Nineteen students (14%) consisting of 10 preclinical (14.7%) and 9 clinical (13.2%) were nasal carriers of S. aureus. However, none of the S. aureus isolates were MRSA. No PVL gene was detected but eight of them were positive for -haemolysin gene. Conclusion: There were no MRSA nasal carriers among the medical students, but a low prevalence of S. aureus nasal carriers was detected. These carriers do not pose as high risk because none of the strains of S. aureus possess both the -haemolysin toxin and the PVL toxin that are associated with tissue necrosis.

Download Full-text

Nasal carriage of methicillin-resistant Staphylococcus aureus among preclinical medical students: epidemiologic and molecular characteristics of methicillin-resistant S. aureus clones

Diagnostic Microbiology and Infectious Disease ◽

10.1016/j.diagmicrobio.2010.12.004 ◽

2011 ◽

Vol 70 (1) ◽

pp. 22-30 ◽

Cited By ~ 33

Author(s):

Xiao Xue Ma ◽

Dan Dan Sun ◽

Si Wang ◽

Mei Lian Wang ◽

Miao Li ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Medical Students ◽

Methicillin Resistant Staphylococcus Aureus ◽

Nasal Carriage ◽

Molecular Characteristics ◽

Methicillin Resistant ◽

Preclinical Medical Students

Download Full-text

Nasal carriage of Staphylococcus aureus in farm animals and breeders in North of Morocco

10.21203/rs.3.rs-15742/v5 ◽

2020 ◽

Author(s):

Nadira Mourabit ◽

Abdelhay Arakrak ◽

Mohammed Bakkali ◽

Zeineb Zian ◽

Joaira Bakkach ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Susceptibility ◽

Virulence Genes ◽

Nasal Carriage ◽

High Rate ◽

Farm Animals ◽

Carriage Rate ◽

Increased Risk ◽

Significant Difference ◽

Mrsa Strains

Abstract Background: The objectives of this study were to determine for the first time, in Morocco, the nasal carriage rate, antimicrobial susceptibility profiles and virulence genes of Staphylococcus. aureus isolated from animals and breeders in close contact.Methods: From 2015 to 2016, 421 nasal swab samples were collected from 26 different livestock areas in Tangier. Antimicrobial susceptibility phenotypes were determined by disk diffusion according to EUCAST 2015. The presence of nuc , mec A, mec C, lukS/F-PV, and tst genes were determined by Polymerase Chain Reaction (PCR) for all isolates.Results: The overall S. aureus nasal carriage rate was low in animals (9.97%) and high in breeders (60%) with a statistically significant difference, (OR= 13.536; 95% CI = 7.070- 25.912; p< 0.001). In general, S. aureus strains were susceptible to the majority of antibiotics and the highest resistance rates were found against tetracycline (16.7% in animals and 10% in breeders). No Methicillin-Resistant S. aureus (MRSA) was detected in animals and breeders. A high rate of tst and lukS/F-PV genes has been recovered only from animals (11.9% and 16.7%, respectively).Conclusion: Despite the lower rate of nasal carriage of S. aureus and the absence of MRSA strains in our study, S. aureus strains harbored a higher frequency of tst and lukS/F-PV virulence genes, which is associated to an increased risk of infection dissemination in humans. This highlights the need for further larger and multi-center studies to better define the transmission of the pathogenic S. aureus between livestock, environment, and humans.

Download Full-text

Nasal carriage of Staphylococcus aureus in livestock in North of Morocco

10.21203/rs.3.rs-15742/v1 ◽

2020 ◽

Author(s):

Nadira Mourabit ◽

Abdelhay Arakrak ◽

Mohammed Bakkali ◽

Zeineb Zian ◽

Joaira Bakkach ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Susceptibility ◽

Virulence Genes ◽

Close Contact ◽

Nasal Carriage ◽

High Rate ◽

Carriage Rate ◽

Increased Risk ◽

Significant Difference ◽

Mrsa Strains

Abstract Background : In Morocco, data of LA-MRSA nasal carriage are still limited. The objectives of this study were to determine for the first time the nasal carriage rate, antimicrobial susceptibility profiles and virulence genes of S aureus isolated from animals and breeders in close contact. Methods : From 2015 to 2016, 480 nasal swab samples were collected from 27 different Livestock areas in Tangier. The antimicrobial susceptibility phenotypes were determined by disk diffusion according to EUCAST 2016. The presence of nuc , mec A and his homologue mec C, lukS/F-PV, and tst genes were determined by PCR for all isolates. Results : The overall S. aureus nasal carriage rate was low in animals (9.97%) and high in breeders (60%) with a statistically significant difference, (OR = 14.321; 95% CI = 7.484- 27.405; p< 0.0001). In general, S. aureus strains were susceptible to the majority of antibiotics and the higher resistance rates were found against tetracycline (16.7% in animals and 10% in breeders). No MRSA was detected in animals and breeders. A high rate of tst and lukS/F-PV genes has been found only in animals (11.9% and 16.7%, respectively). Conclusion : Despite the lower colonization rate of S. aureus and the absence of MRSA strains in our study, S. aureus strains harbored a higher frequency of tst and lukS/F-PV of virulence genes, which is associated to an increased risk of infection dissemination in humans. This highlights the need for implementing adequate approaches for prevention. Further larger and multi-center studies are needed to validate and confirm our findings. Keywords: Staphylococcus aureus , nasal carriage, animals, breeders, MRSA, Morocco

Download Full-text

IS ACQUISITION OF METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS - AN OCCUPATIONAL HAZARD FOR MEDICAL STUDENTS IN INDIA?

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2017.v10i12.20865 ◽

2017 ◽

Vol 10 (12) ◽

pp. 141 ◽

Cited By ~ 1

Author(s):

Shreyas K ◽

Radhakrishna M ◽

Ashwini Hegde ◽

Pooja Rao

Keyword(s):

Staphylococcus Aureus ◽

Medical Students ◽

Susceptibility Testing ◽

Tertiary Care ◽

Nasal Carriage ◽

Occupational Hazard ◽

Carriage Rate ◽

Methicillin Resistant ◽

Drug Resistant Strains ◽

Hospital Acquired

Objective: The incidence of community-acquired and hospital-acquired Staphylococcus aureus infections has been rising with increasing emergence of drug-resistant strains called methicillin-resistant S. aureus (MRSA). The main objective of this study was to determine the prevalence of carriage rate of MRSA among the interns of tertiary care teaching hospital in Mangalore.Methods: A total of 150 interns were participated, thereby swabs from both anterior nares were collected and processed for S. aureus. The isolated strains of S. aureus were screened for methicillin susceptibility by modified Kirby–Bauer method using cefoxitin (30 μg) disc. Further, antibiotic susceptibility testing for all isolates of S. aureus was also done against selected appropriate antibiotics. Vancomycin susceptibility testing for MRSA was done by E test.Results: The number of strains of S. aureus isolated from our 150 participants was 71 with a percentage rate of 47.3. Of the 71 isolates of S. aureus, one (1.4%) was MRSA. The overall MRSA carriage rate was 0.66%. The S. aureus and MRSA carriage rates recorded in this study were at par and significantly lower, respectively, when compared with other reported studies. It was observed that risk factors such as the use of antibiotics in the past 6 months and smoking were found to be statistically significant in nasal carriage status of S. aureus (<0.05). The only one isolate of MRSA was found to be sensitive to vancomycin, linezolid, and teicoplanin.Conclusion: It was concluded that the acquisition of S. aureus and MRSA would not be an occupational hazard for medical students of developing countries like India.

Download Full-text

Characterization ofStaphylococcus aureusIsolates That Colonize Medical Students in a Hospital of the City of Cali, Colombia

International Journal of Microbiology ◽

10.1155/2015/358489 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 3

Author(s):

Luis Fernando Collazos Marín ◽

Gina Estupiñan Arciniegas ◽

Monica Chavez Vivas

Keyword(s):

Staphylococcus Aureus ◽

Medical Students ◽

Pcr Amplification ◽

Nasal Carriage ◽

Clinical Rotation ◽

Carriage Rate ◽

Methicillin Resistant ◽

Hospital Environments ◽

The City

Introduction. Nasal carriage of methicillin-resistantStaphylococcus aureus(MRSA) represents a risk for the spread of bacteria. This study characterized theS. aureusisolated from medical students, who were in their clinical rotation at a hospital in the city of Cali.Materials and Methods. 216 students participated in the study and 63 isolates ofS. aureuswere evaluated for susceptibility and PCR amplification ofagrandmecA genes. The origin of MRSA isolates was established by analyzingagrpolymorphisms.Results. A total of 29.2% of students were colonized byS. aureusand nasal carriage rate was 23.6% and 14.3% MRSA. Threeagrgroups (agrII, andagrIII) were identified; theagrI group was the most common, with a 35% prevalence; this group is from community origin.Conclusion. The present study demonstrates that medical students carryS. aureusstrains, with the threat of spreading them both to community and hospital environments.

Download Full-text

Nasal carriage of Staphylococcus aureus in farm animals and breeders in North of Morocco

10.21203/rs.3.rs-15742/v6 ◽

2020 ◽

Author(s):

Nadira Mourabit ◽

Abdelhay Arakrak ◽

Mohammed Bakkali ◽

Zeineb Zian ◽

Joaira Bakkach ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Susceptibility ◽

Virulence Genes ◽

Close Contact ◽

Nasal Carriage ◽

High Rate ◽

Farm Animals ◽

Carriage Rate ◽

Increased Risk ◽

Significant Difference

Abstract Background: The objectives of this study were to determine for the first time, in Morocco, the nasal carriage rate, antimicrobial susceptibility profiles and virulence genes of Staphylococcus. aureus isolated from animals and breeders in close contact.Methods: From 2015 to 2016, 421 nasal swab samples were collected from 26 different livestock areas in Tangier. Antimicrobial susceptibility phenotypes were determined by disk diffusion according to EUCAST 2015. The presence of nuc, mecA, mecC, lukS/F-PV, and tst genes were determined by Polymerase Chain Reaction (PCR) for all isolates. Results: The overall S. aureus nasal carriage rate was low in animals (9.97%) and high in breeders (60%) with a statistically significant difference, (OR= 13.536; 95% CI = 7.070- 25.912; p< 0.001). In general, S. aureus strains were susceptible to the majority of antibiotics and the highest resistance rates were found against tetracycline (16.7% in animals and 10% in breeders). No Methicillin-Resistant S. aureus (MRSA) was detected in animals and breeders. A high rate of tst and lukS/F-PV genes has been recovered only from animals (11.9% and 16.7%, respectively).Conclusion: Despite the lower rate of nasal carriage of S. aureus and the absence of MRSA strains in our study, S. aureus strains harbored a higher frequency of tst and lukS/F-PV virulence genes, which is associated to an increased risk of infection dissemination in humans. This highlights the need for further larger and multi-center studies to better define the transmission of the pathogenic S. aureus between livestock, environment, and humans.

Download Full-text

Nasal carriage rate and antimicrobial resistance pattern of Staphylococcus aureus among the food handlers in Canton Sarajevo, Bosnia and Herzegovina

Journal of Health Sciences ◽

10.17532/jhsci.2020.882 ◽

2020 ◽

Author(s):

Sabina Šegalo ◽

Daniel Maestro ◽

Zarema Obradović ◽

Anes Jogunčić

Keyword(s):

Public Health ◽

Staphylococcus Aureus ◽

Antimicrobial Resistance ◽

Bosnia And Herzegovina ◽

Antimicrobial Susceptibility ◽

Susceptibility Testing ◽

Nasal Carriage ◽

Antimicrobial Susceptibility Testing ◽

Food Handlers ◽

Carriage Rate

Introduction: The nasals and hand carriage of Staphylococcus aureus in food handlers (FHs) represent a significant source of Staphylococcal food contamination and food poisoning. Antimicrobial resistance (AMR) is a microorganism’s ability to resist the action of one or more antimicrobial agents. S. aureus has demonstrated the ability to rapidly respond to each new antimicrobial with the development of a resistance mechanism. The aim of the study was to assess the prevalence of nasal carriage rate and AMR pattern of isolated strains S. aureus among FHs in Canton Sarajevo, Bosnia and Herzegovina. Methods: The retrospective study included laboratory results of 11.139 tested subjects between January 2014 and December 2018. The study was conducted in the laboratory of the Institute of Public Health of the Federation of Bosnia and Herzegovina in Sarajevo. Samples of nasal swabs were collected from FHs, employees in companies located in Canton Sarajevo, during sanitary surveillance prescribed by applicable legal standards. S. aureus isolates were identified according to conventional microbiological methods and antimicrobial susceptibility testing was performed by the agar disk diffusion method according to the European Committee on Antimicrobial Susceptibility Testing; 2013 standard. Results: Among the 11.138 subjects, 792 (7.1%) were carriers of S. aureus. Isolated strains were tested on eight different antibiotics, and the resistance to penicillin, ampicillin, and amoxicillin was 788 (99.5%), 776 (97.9%), and 752 (94.9%), retrospectively. In total, 86.36% of isolated strains were multidrug-resistant. Conclusions: The low percentage of S. aureus carriers indicates that preventive measures of carrier control are being actively implemented within the legally prescribed measures. The emergence of numerous isolated strains with multidrug-resistance characteristics is a significant public health problem and consequently limits the range of antibiotics available for therapeutic purposes. The results of this research indicate that AMR has increased in Sarajevo Canton and it is following the trend of global growth.

Download Full-text