Methicillin-resistant Staphylococcus Aureus Carriage Rate Research Articles

Prevalence of and Risk Factors Associated with Methicillin-Resistant Staphylococcus aureus (MRSA) Carriage Among Cutting Specialties at the Ospital ng Maynila Medical Center

Objective: To determine the point prevalence of, and risk factors associated with MRSA carriage among resident physicians of surgical departments at the Ospital ng Maynila Medical Center. Methods: Design: Cross-sectional Study Setting: Tertiary Government Training Hospital Participants:51 resident physicians from different surgical departments (general surgery, obstetrics and gynecology, ophthalmology, otorhinolaryngology – head and neck surgery and dermatology) underwent nasal and pharyngeal swabs with microbial culture and sensitivity testing to identify MRSA carriers. Fisher Exact Test and logistic regression were utilized to determine associations between MRSA carriage and various risk factors including frequency of hand washing and departmental affiliation. Results: Overall prevalence rate of MRSA carriage was 9.8%. Otorhinolaryngology residents had the highest combined prevalence of MRSA of 42.9%, significantly higher compared to other departments and were used as a reference in logistic regression analyses. Notably, handwashing only once daily was associated with a 20-fold increase in the risk of MRSA carriage (OR 20.5, 95% CI: 1.82 to 230, p = .014). Other departments did not demonstrate statistically significant differences in MRSA carriage rates. Conclusions: Otorhinolaryngology resident physicians had the highest combined prevalence of MRSA and nasal MRSA was found only in otorhinolaryngology residents. The surgical subspecialty and frequency of handwashing of the healthcare worker were identified as important risk factors to develop MRSA carriage. Targeted interventions (including enhanced infection control protocols and regular screening) are needed especially in high-risk departments.

SCREENING OF METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS AMONG HEALTHCARE WORKERS AND THEIR ANTIBIOTIC SUSCEPTIBILITY PATTERN IN A TERTIARY CARE HOSPITAL

Objective: Colonization of Staphylococcus aureus in the nasal flora has been proven to play an important role in the transmission of infections. Health care workers carrying Staphylococcus aureus in their nose or skin play an important role in cross-contamination and thus result in Methicillin-resistant Staphylococcus aureus (MRSA) related hospital-acquired or community-acquired infections. Implementation of hand hygiene methods and standard precautions are helpful in reducing transmission and controlling spread. Screening for carriage of MRSA is fundamental step in nosocomial infection control. The present study was undertaken to determine the prevalence of MRSA carriage rate and study their antibiogram.
 Methods: A cross-sectional study was conducted for a period of six months and samples from 185 HCWs working in high-risk areas were processed by standard protocols. As per CLSI guidelines, MRSA detection by disc diffusion method using Cefoxitin disc (30μg) and further determined by Epsilometer test (E-test) by interpreting Minimum inhibitory concentration (MIC) values (mcg/ml).
 Results: Out of 185 nasal swabs, 53 were Staphylococcus aureus isolates. MRSA colonization is seen in (8.64%) samples. Preponderance was seen in staff nurses (10.16%). Antibiogram of MRSA isolates showed sensitivity to Vancomycin and linezolid.
 Conclusion: The present study was undertaken to screen nasal carriage of MRSA among healthcare workers, as they pose a potential risk factor for nosocomial transmission leading to MRSA outbreaks. The strengthening of Infection prevention and control measures institutionalization of antimicrobial stewardship programs helps in curbing the spread of MRSA.

MRSA carriage among healthcare workers in a Vietnamese intensive care unit: a prospective cohort study.

Background: Little is known about the magnitude and patterns of methicillin-resistant Staphylococcus aureus (MRSA) carriage among intensive care unit (ICU) healthcare workers (HCWs), especially in lower-middle-income countries like Vietnam. Materials and methods: A prospective cohort study was conducted on HCWs working in the adult ICU of the Hospital for Tropical Diseases in Vietnam between October 28 and December 20, 2019. These HCWs included physicians, nurses, and nursing assistants who were responsible for all essential medical activities and basic patient care. A questionnaire was used to collect participants’ information, including age, sex, profession, ICU working time, and underlying diseases. Hand and nasal swabs were collected weekly for 8 consecutive weeks for MRSA screening. Staphylococcal isolates were checked for catalase and coagulase and, for methicillin resistance using cefoxitin disk diffusion, then rechecked on the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Results: Among 55 HCWs, 16 (29.1%) carried MRSA in their noses or hands. MRSA intermittent hand carriage was documented in 2 (3.6%) HCWs. Among 53 HCWs undertaking nasal swabs, 13 (24.5%) were MRSA persistent and 3 (5.6%) were intermittent carriers. The MRSA carriage rate was highest among nursing assistants (50%, 4/8). More HCWs with underlying diseases were found to be MRSA carriers (31.8%, 7/22) compared with those without comorbidities (27.3%, 9/33). Conclusion: MRSA carriage among HCWs is not rare. The findings highlight an urgent need to review and update the local infection prevention and control measures to prevent MRSA transmission from HCWs to patients.

EPIDEMIOLOGICAL TOOL IN THE STUDY OF MRSA NASAL CARRIAGE AMONG HEALTH CARE WORKERS OF TERITARY CARE HOSPITAL - ITS UTILITY

Background And Objectives: Staphylococcus aureus is a common cause of community and hospital acquired infections. Methicillin resistant Staphylococcus aureus (MRSA) is a common nosocomial pathogen in the ICUs and other parts of the hospital and presents a challenge for all health care institutions. One of the important sources of MRSA in hospital setting is nasal carriage among health care workers (HCW's). Thus screening of health care workers for MRSA carriage will be helpful in preventing spread of MRSA from colonized health care workers to patients. The objective of the study is to to estimate the prevalence of nasal carriage of MRSA among health care workers of our institution. It is a prospective study done at Institute of Microbiology, Madurai Materials And Methods: Medical College, Madurai with the study period of two months. Nasal swabs collected from 100 healthcare workers working in different departments of our tertiary care hospital. All the swabs were inoculated on to Mannitol salt agar plates and incubated at 37°c for 24hrs to isolate Staphylococcus aureus. MRSA strains were identied by disc diffusion method using Cefoxitin (30฀g) disc. Results: Out of 100 HCWs, 21 (21%) were nasal carriers of S.aureus and among them 2(2/21) (9.5%) were carrier of MRSA. The overall nasal carriage rate of MRSA was 2%(2/100). S. aureus carriage rate was highest among Staff nurses 27.7 % (5/18) while MRSA carriage rate was highest among Interns 3.3%(1/30). In our study, nasal Conclusion: carriage of MRSA among the health care workers is 2 % with the rate being highest among Interns. Considering the fact that Health Care Workers are more involved in the patient care activities, it is necessary to sensitize them regarding this issue and we should emphasize the importance of hand washing on them.

Staphylococcus aureus Nasal and Hand Carriers and the Prevalence of Methicillin Resistant Staphylococcus aureus (MRSA) Among School Children in Gharyan City

Background: Staphylococcus aureus infections are increasingly reported from both health institutions and communities around the world. In particular, infections due to methicillin-resistant Staphylococcus aureus (MRSA) strains have been detected worldwide. If MRSA becomes the most common form of S. aureus in a community, it makes the treatment of common infections much more difficult. But, reports on the current status of community acquired MRSA in the study area are non-existent. Aim: To determine nasal and hand carriage of S. aureus and the prevalence of MRSA isolates among school children in Gharyan city. Methods: This study was a cross sectional descriptive study carried out over a period of three months in three basic education schools in Gharyan city. Children were recruited into the study after getting consent from schools headmasters. Nasal swabs and fingerprints were collected from 120 children and taken to Microbiology laboratory of science faculty, Gharyan University, where conventional culture techniques, characterization of S. aureus and determination of MRSA using Kirby Bauer Disc Diffusion method were performed. Results: Out of a total of 240 nasal swabs and fingerprints, 48 (20%) S. aureus isolates were identified. S. aureus carriage rate was the highest among males, higher at hands than nares and lower among age group 11-15 years than 5-10 years. The overall prevalence of MRSA among S. aureus isolates was 39.6 %. MRSA carriage rate was lower among females than males, the lowest at hands and higher among age group 11-15 years than 5-10 years. Conclusion: This is the first study to assess S. aureus carriage and the MRSA prevalence among children aged 5-15 years in Gharyan city schools. S. aureus was isolated from only 20% of the nares and hands of children included in this study.

Methicillin-resistant Staphylococcus aureus (MRSA) carriage among health care personnel in nonoutbreak settings in tertiary care hospital in Mysore

Methicillin-resistant Staphylococcus aureus (MRSA) is a multidrug resistant organism recognized as major cause of infections ranging from relatively minor skin and soft tissue infections to life-threatening systemic infections. Contact transmission from health care personnel (HCP) to the patients provides the main mode of transmission of MRSA. Screening of HCPs colonized with MRSA may aid in preventing spread of this organism. Two samples were collected from 200 HCP which included sample from anterior nares and web spaces of both hands. Identification of Staphylococcus aureus and MRSA strains were done as per standard operating protocol. Results were compiled, tabulated, and all data were subjected to SPSS, version 17.0 software for analysis. About 25.5% (51 HCPs) were carriers of S aureus and among them 6.5% (13 HCPs) were carriers of MRSA. Among the MRSA carriers, 28.4% were physicians, followed by nursing interns (21.1%), MBBS interns (9%), nurses (5.4%), and others, that is, physiotherapist, housekeeping staff, and helping staff (37.5%). In spite of having infection control policies in place, MRSA carriage rate was 6.5%. This signifies the importance of periodic systematic screening of all HCPs and decolonization, which may help in eliminating the burden of MRSA carrier status and spread of infection in the health care setting.

Methicillin Resistant Staphylococcus aureus in Health Care Workers of a Tertiary Care Infectious Disease Hospital in Nepal

Objectives: Acquisition of mecA gene in infectious strains of Methicillin resistant Staphylococcus aureus (MRSA) are considered as one of the potential virulence factors that enables the host bacteria to carry out several nosocomial and community-acquired infections. The main aim of this study was to determine the prevalence of MRSA, their antibiogram and mecA gene in the bacterial isolates obtained from the asymptomatic healthcare workers (HCWs) working in Sukraraj Tropical and Infectious Disease Hospital (STIDH), Kathmandu Nepal.
 Methods: This prospective cross-sectional study involved the collection of nasal and hands swab of 125 randomly selected HCWs from December 2019 to February 2020. Conventional microbiological methods were used to isolate and identify S. aureus. Antimicrobial susceptibility testing was done by modified Kirby Bauer disc diffusion method. MRSA was confirmed by using cefoxitin disc. Detection of mecA gene in the chromosome which was extracted by Phenol: Chloroform: isoamyl alcohol DNA extraction method, amplified by using PCR and visualized by running agarose gel electrophoresis.
 Results: The overall and MRSA carriage rate among the HCWs was found to be 28% (35/125) and 10.4% (13/125) respectively. S. aureus carriage rate was highest among sanitation staffs (34.2%) followed by pharmacy staffs (33.3%), laboratory personnel (18.8%), doctors (9.1%) and nurses (7.5%). Similarly, 34.2% (13/38) of the S. aureus isolates were resistant to methicillin, 31.6% (12/38) were inducible-clindamycin resistant and 63.2% (24/38) of them were multi-drug resistant (MDR). All the 13 MRSA isolates harbored the mecA gene.
 Conclusions: Carriage rate of MRSA among HCWs was high and alarming, indicating the prompt need of intervention measures to curb the growth and spread of resistant isolates in the hospital settings. Effective surveillance (of infectious diseases) and establishment of advanced diagnostic facilities can assist in estimating the actual burden of the MRSA which in turn helps to formulate and implement the appropriate policies and infection-control programs to address the increasing antimicrobial resistance in the country.

Nasal Methicillin-Resistant Staphylococcus aureus Carriage Among Foreign Workers Recruited to Taiwan From Southeastern Asian Countries.

BackgroundIn 2012, we identified the dissemination of methicillin-resistant Staphylococcus aureus (MRSA) sequence type (ST)45 strain in 14 nursing homes in Taiwan and foreign nurse workers, a significant risk factor for MRSA carriage. We conducted this study to understand MRSA carriage and molecular characteristics among foreign workers recruited from Southeastern Asian countries.MethodsA cross-sectional study involving a total of 1935 foreign workers—929 (arrival group) and 1006 (staying group)—from Vietnam (n = 843), Indonesia (n = 780), the Philippines (n = 239), and Thailand (n = 70) were conveniently recruited during upon-arrival and regular health examination in a regional hospital. A nasal swab was obtained from each participant for detection of MRSA.ResultsOverall, MRSA carriage rate was 2.72%, with 2.26% for arrival group and 3.18% for staying group, and 4.74% for Vietnamese, 1.28% for Indonesians, 1.26% for Filipino, and none for Thai workers. Pulsotype AK/ST45 (57%) and pulsotype AX/ST188 (14%) were the top 2 dominant clones for the arrival group, whereas pulsotype D/ST59 (41%) (an endemic community clone in Taiwan) and pulsotype AK/ST45 (19%) were predominant for the staying group. A significant decrease of pulsotype AK/ST45 from 57% to 19% (P = .007) and increase of pulsotype D/ST59 from 4.8% to 41% (P = .004) were found between the arrival and the staying groups.ConclusionsApproximately 3% of foreign workers recruited from Southeastern Asian countries to Taiwan were colonized with MRSA, including the ST45 strain. However, the MRSA isolates from workers staying in Taiwan were mostly a locally endemic clone and genetically different from those identified from workers on arrival.

Methicillin-Resistant Staphylococcus aureus Prevalence Among Healthcare Workers in Contact Tracings in a Dutch Hospital

Background: In The Netherlands, the national guidelines on Methicillin-Resistant Staphylococcus aureus (MRSA) prevention and control advocate screening of healthcare workers (HCWs) after unprotected exposure to MRSA carriers. Although this strategy is largely successful, contact tracing of staff is a time-consuming and costly component. We evaluated our contact tracing policy for HCWs over the years 2010–2018. Methods: A retrospective, observational study was performed in a Dutch teaching hospital. All HCWs who had unprotected contact with an MRSA carrier were included in contact tracing. When there had been a long period of unprotected admission prior to an MRSA finding, or when the index case was an HCW, the entire (nursing) team was tested. All samples of HCWs who were tested for MRSA carriage as part of contact tracing from 2010 until 2018 were included. A pooled nose, throat, and perineum swab was collected using the eSwab medium (Copan) and inoculated on chromID MRSA agar plates (bioMérieux) after enrichment in a broth. Molecular typing was performed using multiple-locus variable number of tandem repeat analysis (MLVA). Results: In total, we included 8,849 samples (range, 677–1,448 samples per year) from 287 contact tracings (range, 26–55 contact tracings per year). Overall, 32 HCWs were colonized with MRSA (0.36%; 95% CI, 0.26%–0.51%). None of them developed a clinical infection. Moreover, 8 HCWs (0.10%; 95% CI, 0.05%–0.19%) were colonized with the same MLVA type as the index case and were detected in 6 of 287 contact tracings (2%). In 4 of 8 of these cases, a positive HCW was the index for undertaking contact tracing. In 3 of 8 cases, it was clear that the HCW who was identified in the contact tracing was the source of the outbreak and was the cause of invasive MRSA infections in patients. Notably, a different MLVA type as the index case was found in 24 HCWs (0.27%; 95% CI, 0.18%–0.40%) of whom 7 of 24 HCWs (29.2%) were intermittent carriers. Conclusions: This study revealed a sustained low MRSA prevalence among samples in contact tracing of HCWs over 9 years. Furthermore, it shows that when MRSA contact tracing is performed according to the national guideline, only 1 of 1,000 samples results in a secondary case. This is similar to the population carriage rate of MRSA in The Netherlands. More frequently, an unrelated strain is found. These findings raise questions regarding the efficacy of the current strategy to perform contact tracing after unprotected exposure.Funding: NoneDisclosures: None

Prevalence Of Methicillin-Resistant Staphylococci Among Apparently Healthy Students Attending A Tertiary Institution In Benin City, Nigeria

This study was aimed at determining the prevalence of methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant coagulase negative staphylococci (MRCoNS) among apparently healthy students of a tertiary institution in Benin City, Nigeria. A total of 350 students were recruited for the study and nasal swabs were collected alongside demographic data. These swabs were processed microbiologically using standard techniques to recover staphylococci. Antimicrobial susceptibility and methicillin-resistance was determined using a phenotypic method (cefoxitin resistance). A total of 148 (42.3%) of 350 students were culture positive for S. aureus, while 72 (20.6%) were positive for CoNS. Students from Faculty of Dentistry showed the highest prevalence of nasal MRSA (40.0%) and MRCoNS (20.0%). Ofloxacin and gentamicin were the most active antibacterial agents against MRSA with 89.1% and 87.3% respectively been susceptible, while gentamicin was the most active antibiotic against MRCoNS (75.0%). Nasal colonization by MRSA and MRCoNS was unaffected by area of residence and gender (P > 0.05). The nasal carriage rate of MRSA and MRCoNS was 37.2% and 33.3% respectively. The study recommends periodic review of nasal colonization rates among apparently healthy subjects. Regulated use of antimicrobial agents is imperative in order to stem the tide of resistance.
 Keywords: Methicillin-resistance, Staphylococci, Students, Antibiotics

Inducible Clindamycin and Methicillin Resistant Staphylococcus aureus Among Cancer Patients at University of Gondar Compressive Specialized Hospital, Northwest Ethiopia: Carriage Rate and Antibiotic Resistance Patterns.

Methicillin-resistant Staphylococcus aureus (MRSA) is a type of Staphylococcus aureus strain which is resistant to a group of beta-lactam antibiotics. Methicillin-resistance is due to a penicillin-binding protein, which has a low affinity for beta-lactam antibiotics. Excess and inappropriate use of clindamycin have led to the emergence of resistant Staphylococcal strains. Cancer patients are at high risk of bacterial colonization due to cancer chemotherapy which leads to severe and prolonged immunosuppression. This study aimed to assess the carriage rate of inducible clindamycin and MRSA among cancer patients. A hospital-based cross-sectional study was conducted on 200 cancer patients from January to August 2019. Sociodemographic data and nasal swab samples were collected and inoculated on mannitol salt agar and then incubated at 37°C for 24 hours. The identification of isolates was done by colony characteristics and biochemical reactions. MRSA was detected using cefoxitin disc and inducible clindamycin resistance detected using D-test. Interpretations of antibiotics susceptibility was done using CLSI 2018. Finally, data was entered, cleared, and checked using Epi-info version 7 and exported to SPSS version 20 for analysis. Logistic regression was used for statistical association. p-value ≤ 0.05 at 95% CI was considered statistically significant. In this study, of the 59 Staphylococcus aureus isolates tested, 22% (13/59) were MRSA and 78% (46/59) were MSSA. MRSA carriage rate in females was 18.6% (11/59) whereas in males it was 3.4% (2/59). MRSA carriage among urban residents (15.3% (9/59)) was higher than their rural counterparts (6.8% (4/59)). The prevalence of inducible clindamycin resistance was 17% (10/59). Multi-drug resistance patterns among Staphylococcus aureus isolates was 55.9% (33/59). Clindamycin (84.6%), chloramphenicol (84.6%), and ciprofloxacin (69.2%) were the most effective whereas penicillin (100%), tetracycline (76.9%), and erythromycin (76.9%) were the least effective for MRSA isolates. Urban living, being illiterate, being employed, patients with liver and lung cancer were significantly associated with MRSA carriage. This study showed high rates of MRSA carriage and inducible clindamycin resistance with the percentages of 22 and 17, respectively. Therefore, decolonization of MRSA carriers and rational usage of antibiotics should be implemented.

Promising anti-microbial effect of apple vinegar as a natural decolonizing agent in healthcare workers

ABSTRACT Introduction Colonized Healthcare workers (HCWs) are an essential reservoir of nosocomial infections. This study aims to determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) carriage rate among HCWs, to evaluate at Fayoum University Hospital the susceptibility of isolates to mupirocin and Chlorhexidine and to investigate the antimicrobial effect of different vinegars on MRSA as a natural decolonizing agent. Methods Nasal and hand swabs were collected from 124 HCWs at Fayoum University Surgical Hospital. Isolates were identified using the standard microbiological methods. Susceptibilities to mupirocin and Chlorhexidine were determined by disk diffusion and broth micro-dilution. Screening antimicrobial effect of commercial vinegars was determined by agar well-diffusion method and microdilution method. Results About one tenth 11.3% (14/124) of HCWs showed nasal carriage of MRSA. Workers were the predominant carriers (P = 0.013). The overall non-nasal carriage rate of MRSA was 6.5% (8/124). Among MRSA isolates Low-level Mupirocin resistance (LLMR) showed in (36.4%, 8/22). MICs ranged from 0.25 to 32 µg/ml. Also, (13.6 %, 3/22) showed Chlorhexidine resistance, MICs ranged from 0.039 to 5 µg/ml. Apple vinegar showed the highest susceptibility among vinegars (p < 0.0001) with MIC values varied from 0.058 to 1.87 μg/ml Discussion The emergence of mupirocin (36.4%) and Chlorhexidine (13.6%) resistant Staphylococcus aureus among HCWs should be of excessive concern. Apple vinegar has a promising antimicrobial effect against MRSA isolates and could be used as a decolonizing agent.

PREVALENCE OF NASAL CARRIAGE OF METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS AMONG HEALTHCARE WORKERS IN THE DEPARTMENTS OF OTORINOLARYNGOLOGY AND DENTISTRY IN KYIV, UKRAINE

The aim: To obtain the first estimates of the current prevalence of nasal carriage of methicillin-resistant Staphylococcus aureus (MRSA) among healthcare workers (HCWs) in the departments of Otorinolaryngology and Dentistry and to determine of genes virulence factors (Panton Valentine Leukocidine (PVL) genes). Materials and methods: We performed a multicenter cross-sectional study. The susceptibility to antibiotics was determined by disk diffusion method according to the European Committee on Antimicrobial Susceptibility Testing. The virulence factor encoding genes, mecA, lukS-lukF, were detected by Polymerase Chain Reaction (PCR). Results: Incidence rate of S. aureus nasal carriage among HCWs was 36.2%, whereas MRSA carriage was 17%. Prevalence of MRSA carriage rate was 34.9% in Otorhinolaryngology departments and 9.7% in Dentistry. PCR testing confirmed that all MRSA strains were mecA gene-positive. The virulence factor encoding genes were detected in 82.3% of the S. aureus isolates from HCWs. Among S.aureus, the lukS-lukF genes were detected in over 59% of the strains. The lukS-lukF genes were detected in 55.5% of MRSA and in 58.9% of MSSA strains. LukS-lukF genes were most commonly co-present in MRSA strains. No significant difference was detected between the occurrences of lukS-lukF genes (P > 0.05). Conclusions: Personnell in otorhinolaryngology and dentistry departments have a high rate of nasal colonization of MRSA. This carrier state may be an important risk factor for transmission MRSA from physicians and nurses to patients and vice-versa. Screening for MRSA nasal carriage of HCWs is a key element in enabling infection control measures and early therapeutic decisions.

Nasal and Hands Carriage Rate of Methicillin-Resistant Staphylococcus aure-us among Health Care Workers at Alwahda Hospital, Derna

Increasing incidence of Methicillin-Resistant Staphylococcus aureus (MRSA) is a well-documented healthcare and community phenomenon of concern to medical and public health communities all over the world. One of the most important sources of MRSA infection in hospitals is health care workers (HCWs) through nasal or hands carriage. The aim of this study is to determine the rate of methicillin-resistant Staphylococcus aureus among HCWs. A cross-sectional study involving 102 HCWs was conducted at Alwahda hospital, Derna. Nasal and hand swabs were collected and cultured on Mannitol Salt Agar. Gram staining was performed on mannitol fermenting colonies. Slide catalase and coagulase were performed to identify S. aureus. An oxacillin and cefoxitin susceptibility test was carried out on Muller Hinton agar using the modified Kirby-Bauer disc diffusion method. Results: out of 102 healthcare workers, 46 (45.1%) carried S. aureus. The rate of methicillin resistance amongst all S. aureus isolates was 47.8 % (22/46) whereas 21.6 % (22/102) of all HCWs were identified as MRSA carriers. Nurses had the highest MRSA carriage with 53%, compared to other HCW. On the other hand, the highest rate of MRSA (75%) was seen in CCU workers followed by workers of pediatric and surgical wards (66%, 62% respectively). The high rate of nasal and hand MRSA carriage among healthcare workers, especially in high-risk wards, indicates the imperfection of infection control measures in our hospitals and the necessity to improve the infection control program.

Epidemiology and antimicrobial resistance of methicillin-resistant Staphylococcus aureus isolates colonizing pigs with different exposure to antibiotics.

BackgroundIn 2016, very high rates of methicillin-resistant Staphylococcus aureus (MRSA)-ST398 (99%) were found in Portuguese pig farms that used colistin, amoxicillin, and zinc oxide as feed additives. Since then, farms A and B banned the use of colistin, and farm C banned the use of both antibiotics.ObjectiveThe aim of the present study was to evaluate the impact of the ban of colistin and amoxicillin on pig MRSA carriage rates, clonal types and antimicrobial resistance, compared to the results obtained in 2016.MethodsIn 2018, 103 pigs (52 from farm B using amoxicillin only as a feed additive and 51 from farm C where no antibiotics were included in the feed regimen) were nasally swabbed for MRSA colonization. Isolates were tested for antimicrobial susceptibility, and characterised by spa typing, SCCmec typing and MLST. Whole genome sequencing (WGS) was performed for representative isolates.ResultsOverall, 96% of the pigs swabbed in 2018 carried MRSA, mostly ST398-SCCmec V-spa types t011/t108. MRSA from pigs not receiving antibiotics in the feed regimen showed susceptibility to a higher number of antibiotics, namely erythromycin, ciprofloxacin, gentamicin, and chloramphenicol. Notably, most of these isolates (n = 52) presented an unusual erythromycin-susceptibility/clindamycin-resistance phenotype. WGS showed that these isolates lacked the erm and the lnu genes encoding resistance to macrolides and lincosamides, respectively, but carried the vgaALC gene encoding resistance to lincosamides, which is here firstly identified in S. aureus ST398.ConclusionAfter two years the ban of colistin and amoxicillin as feed additives had no significant impact on the MRSA nasal carriage rates. Nevertheless, the MRSA strains circulating in those farms showed resistance to a lower number of antibiotic classes.

Methicillin-resistant Staphylococcus aureus carriage among medical students of Jimma University, Southwest Ethiopia

ObjectivesInfections caused by methicillin-resistant Staphylococcus aureus (MRSA) are often difficult to manage due to its resistance to multiple antibiotics. This study aimed to determine the nasal carriage of MRSA and its antimicrobial susceptibility patterns among medical students at the Jimma University medical center (JUMC), Southwest Ethiopia. MethodsAn institution based cross-sectional study was conducted at the JUMC from May to August; 2016. A total of 371 participants were systematically selected. Demographic data was collected using pre-designed questionnaire. Nasal swabs were collected following standard microbiological methods. MRSA was detected using cefoxitin (30μg) disc (Oxoid, UK); and antimicrobial susceptibility tests were performed by disc diffusion method. ResultsA total of 371 students were included. Of these, 84.9% (315/371) were males. The overall prevalence of nasal carriage of S. aureus and MRSA among medical students at JUMC were 22.1% (82/371) and 8.4 % (31/371), respectively. The carriage rate of MRSA among medical intern (20% (16/80)) was higher compared with clinical year-I (3.6% (6/166)) and year-II (7.2% (9/125)) students. Resistance against trimethoprim-sulfamethoxazole, tetracycline and ciprofloxacin were 83.9%, 64.5% and 51.6%, respectively. Longer stay in hospital was significantly associated with the acquisition of MRSA (X2 = 6.93, P value = 0.031). ConclusionThe prevalence of nasal carriage of MRSA was high. Longer stay in hospital environment was associated with the acquisition of MRSA. These findings suggest that infection control efforts focusing the performance of antimicrobial stewardship could have a significant impact on MRSA incidence in this setting.

Antibiotic-resistant pathogens in different patient settings and identification of surveillance gaps in Switzerland - a systematic review.

The prevalence of antimicrobial resistance (AMR) varies significantly among different patient populations. We aimed to summarise AMR prevalence data from screening studies in different patient settings in Switzerland and to identify surveillance gaps. We performed a systematic review, searching Pubmed, MEDLINE, Embase (01/2000-05/2017) and conference proceedings for Swiss studies reporting on carbapenemase-producing Enterobacteriaceae (CPE), extended-spectrum beta-lactamases (ESBL), mobilised colistin-resistance, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) within different patient settings. We identified 2345 references and included 46 studies. For acute care patients, most screening data come from admission screenings, whereas AMR prevalence among hospitalised patients is largely unknown. Universal admission screenings showed ESBL-prevalences of 5-8% and MRSA-prevalences of 2-5%. For targeted screening, ESBL-prevalence ranged from 14-21%; MRSA-prevalence from 1-4%. For refugees, high ESBL (9-24%) and MRSA (16-24%) carriage rates were reported; returning travellers were frequently (68-80%) colonised with ESBL. Screening data for other pathogens, long-term care facility (LTCF) residents and pediatric populations were scarce. This review confirms high ESBL- and MRSA-carriage rates for risk populations in Switzerland. Emerging pathogens (CPE and VRE) and certain populations (inpatients, LTCF residents and children) are understudied. We encourage epidemiologists and public health authorities to consider these findings in the planning of future surveillance studies.

Nasal carriage of methicillin-resistant Staphylococcus aureus among health-care workers at a tertiary care hospital in Northern India

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is resistant to all beta-lactam antibiotics, including penicillins, cephalosporins, carbapenems, and betalactamase inhibitors. MRSA remains a public health problem globally. MRSA infection increases morbidity, risk of mortality, increased financial burden, and loss of productivity. A major source of MRSA in the hospital environment can be asymptomatically colonized health-care workers (HCWs). Objectives: The aim of the study is to screen nasal swabs collected from HCWs of our hospital for colonization with S. aureus and detect methicillin resistance among them. Materials and Methods: In this cross-sectional study, consenting HCWs were consecutively enrolled. Nasal swabs were collected aseptically from study participants and processed using standard microbiological protocols for the recovery of S. aureus and MRSA. Methicillin resistance was detected by cefoxitin disc diffusion method according to the CLSI guidelines. Results: Out of a total of 184 HCWs studied, the prevalence of S. aureus carriage in anterior nares was 14.6%. The overall MRSA prevalence was 3.8%. Highest carriage rates for MRSA were found in laboratory technicians (7.1%) followed by nursing staff (4.4%). The ophthalmology department had the highest MRSA carriage rate of 22%. Conclusions: Our findings demonstrate that nasal carriage of MRSA among HCWs is relatively low in this study compared to other Indian studies done in tertiary care centres. Further studies are needed to evaluate the incidence of infections due to MRSA in this population.

Knowledge, attitudes and practices regarding methicillin-resistant Staphylococcus aureus (MRSA) infection control and nasal MRSA carriage rate among dental health-care professionals

Dental health-care professionals (DHCPs) with nasal colonisation of methicillin-resistant Staphylococcus aureus (MRSA) can serve as a reservoir for MRSA transmission to others and be exposed to self-contamination with MRSA. Evaluating the knowledge, attitudes and actual practice of DHCPs is imperative for appropriate infection control. Dentists, dental hygienists and dental technologists from Seoul National University Dental Hospital were recruited to participate in a cross-sectional survey and undergo nasal sampling of MRSA. The survey included demographic questions, six questions about knowledge, eight questions about attitudes/perceptions and six questions about practices/behaviours regarding MRSA infection control. Nasal samples from the participants were analysed for MRSA presence, antimicrobial susceptibility and staphylococcal cassette chromosome mec (SCCmec) typing. MRSA carriers underwent decolonisation with topical mupirocin. Among 139 DHCPs, four (2.9%) were nasal MRSA carriers. Decolonisation was successful in three participants. One participant was decolonised with topical fusidic acid after failure to decolonise with mupirocin. Dentists had a higher knowledge score compared with the other professionals (P < 0.05). Dental hygienists scored higher on practice questions compared with the other professionals (P < 0.05). There was a significant, positive correlation between attitude and practice scores (P < 0.01). The nasal MRSA carriage rate among DHCPs is 2.9%, which is higher than that in the general population but lower than that in other health-care professionals. Further education of DHCPs on MRSA, especially regarding its seriousness, is needed to improve MRSA infection control in a dental hospital setting.

Prevalence and molecular characteristics of methicillin-resistant Staphylococcus aureus among nasal carriage strains isolated from emergency department patients and healthcare workers in central Taiwan.

Screening and identification of methicillin-resistant Staphylococcus aureus (MRSA) carriage are helpful for controlling MRSA dissemination in hospitals. The aim of our study was to determine the prevalence of nasal carriages and diversity of MRSA among patients and healthcare workers (HCWs) at two regional hospitals in Taiwan. Nasal swabs were obtained prospectively from 204 patients visiting the emergency department (ED) and 326 HCWs in two regional hospitals in Changhua, Taiwan, between February 2015 and June 2015. All the MRSA isolates were further molecularly characterized. Of the 204 participating patients, the nasal carriage rates of S. aureus and MRSA were 22.1% and 7.8%, respectively. For HCWs, the S. aureus and MRSA carriage rates were 26.1% and 6.1%, respectively. There was no statistically significant difference in MRSA carriage rate between patients and HCWs (P=0.447). Patients receiving hemodialysis were significantly associated with MRSA colonization (P=0.012). The leading three sequence types (ST) were ST59 (16, 44.4%), ST45 (11, 30.6%), and ST239 (3, 8.3%) for all 36 MRSA isolates. ST59/SCCmec IV/t437/PVL-negative and ST45/SCCmec V/t1081/PVL-negative were the predominant clones among HCWs (30%) and participating patients (19%), respectively. Overall, a substantial proportion of patients visiting the ED and HCWs harbored CA-MRSA, mostly ST59 strains, in their nares. It is noteworthy that MRSA ST45 strains supplanted ST239 as the second leading nasal MRSA colonization strain in our study.