Methicillin-resistant Staphylococcus aureus colonization in HIV patients of Arba Minch province, Ethiopia: Carriage rates, antibiotic resistance, and biofilm formation

Methicillin-resistant Staphylococcus aureus colonization among medicine and health science students, Arba Minch University, Ethiopia

Individuals with Methicillin-Resistant Staphylococcus aureus (MRSA) colonized nasal cavities were at greater risk of developing the infection and can serve as potential reservoirs of transmission. Aim of this study is to determine the extent of nasal carriage and associated factors linked to MRSA in medical and health science students of Arba Minch University (AMU), Ethiopia, who are much prone. An institution based cross-sectional study was conducted at AMU from 01st August through 30th November, 2020 by means of a systematic sampling technique using a structured questionnaire. Nasal swabs samples were collected and S. aureus were identified following standard microbiological methods. Methicillin resistance was tested using cefoxitin disk and antimicrobial susceptibility tests were performed by Kirby-Bauer disk diffusion. Biofilm forming ability was phenotypically detected by micro-titer plate assay. Descriptive statistics and multivariable logistic regression analysis were done by Statistical Package for Social Service (SPSS) version 25. The overall prevalence of Staphylococcus aureus and MRSA were 27.1% (70/258) and 7.4% (19/258) respectively. Methicillin-Resistant S. aureus carriage were higher among medical interns, 16.9% (11/65). Isolates in general were co-resistant to antibiotics, such as trimethoprim-sulfamethoxazole (63.2%) and tetracycline (48.4%). Multidrug resistance (MDR) were observed among 52.6% (10/19) of the isolates. Besides, 31.4% (6/19) of MRSA were biofilm producers and all of them were MDR. Multivariable analysis showed that mean exposure for > 2 years to hospital settings [p = 0.048, AOR: 4.99, 95% CI 1.01–24.66] and the habit of sharing clothing and sports equipment [p = 0.017, AOR: 5.43, 95% CI 1.35–21.83] were statistically significant. The overall prevalence of nasal colonized MRSA among students were comparatively lower than that observed in other studies done in Ethiopia itself. An alarming factor is that, 60% of MDR-MRSA were biofilm producers.

Methicillin resistance Staphylococcus aureus nasal carriage and its associated factors among HIV patients attending art clinic at Dessie comprehensive specialized hospital, Dessie, North East Ethiopia

Globally the incidence of nosocomial infections and colonization due to methicillin resistant Staphylococcus aureus (MRSA) has become greater concern. The objective of the study was to determine the prevalence and associated factors of nasal carriage of MRSA with its antimicrobial susceptibility patter among HIV patients attending ART clinic. cross-sectional study was conducted from January 01 to May 30, 2020 at Dessie comprehensive specialized hospital, north east Ethiopia. A total of 206 HIV patients were recruited by applying systematic random sampling technique. Nasal specimen was collected from both anterior nares, and inoculated directly on mannitol salt agar, MacConkey, 5% blood agar. Screening of MRSA and methicillin susceptible Staphylococcus aureus (MSSA) strain was done by using cefoxitin antibiotic disc following modified Kirby-Bauer disc diffusion technique. Bivariable and multivariable logistic regression analyses were performed to assess the associated factors with S. aureus and MRSA. study participants were in the age range between 12 and 72 years and their mean (±SD) age was 41.52 (±11.2). The rate of S. aureus and MRSA colonization was 127/206 (61.7%) and 58/206 (28.2%), respectively. Having job close contact with human [AOR = 4.41; 95% CI = 1.5-13.02; p = 0.007], picking the nose [AOR = 4.38; 95% CI = 1.34-14.29; p = 0.014] and ART failure [AOR = 7.41; 95% CI = 2.08-26.41; p = 0.002] had statistically significant association with MRSA colonization. MRSA showed resistance for tetracycline (53.4%), erythromycin (84.5%), and trimethoprim-sulfamethoxazole (86.2%). Multi-Drug Resistance (MDR) was detected among 96.5% of MRSA and 20.3% of MSSA isolates. the rate of S. aureus and MRSA nasal colonization was high and it has associated with different factors. Understanding and managing MRSA among HIV patients is mandatory and stakeholders should find out the way how to decolonize the bacteria from nasal area.

Relationship between MLSB resistance and the prevalent virulence genotypes among Bulgarian Staphylococcus aureus isolates

The aim of this study was to investigate the rate of resistance to macrolide-lincosamide-streptogramin B (MLSB) antibiotics, the mechanisms underlying this resistance and to evaluate their relationship with virulence genes profiles of 435 Bulgarian clinical isolates Staphylococcus aureus. The highest resistance was observed to penicillin (96.09%), followed by resistance to erythromycin and clindamycin (34.02 and 22.76%, respectively). Of the tested clinical strains of S. aureus, 96.09% contained the blaZ gene associated with penicillin resistance and 11.03%, the mecA gene responsible for methicillin resistance. The most prevalent were the erm genotypes associated with the presence mainly of ermA and ermC genes followed by ermB. The frequency rates of these genes, alone or in combinations were ermA 41.89%, ermB 27.70%, ermC 43.99%. The majority of Bulgarian macrolide resistant S. aureus exhibited cMLS phenotype, in 58.78% (P = 0.0036). The following virulence genotypes were present significantly more often in the macrolide resistant S. aureus isolates among the studied ones: hlg; hlg,seb; hlg,seb,sec; hlg,seb,seh; hlg,sec; hlg,sec,sei; hlg,sec,sei; hlg,sei; hlg,sei,sej; hlg,sej. This survey found correlation between the virulence profiles with a small number of genes and macrolide resistance among Bulgarian clinical S. aureus isolates, in contrast to sensitive strains, which possessed profiles predominantly with multiple genes.

In vitro antibacterial activity of medicinal plants against biofilm-forming methicillin-resistant Staphylococcus aureus: efficacy of Moringa stenopetala and Rosmarinus officinalis extracts

The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) is slowly rising in Ethiopia for the past few decades. Therefore, novel classes of antibiotics are indispensable to combat the increased incidence of newly emerging multidrug-resistant bacteria like MRSA. Terrestrial flora is considered as a reservoir of novel bioactive secondary metabolites as they have provided us with the largest array of natural products. In this background, the present study is intended to evaluate the in-vitro antibacterial efficacy of five medicinal plants (Ocimum lamiifolium Hochst. ex Benth., Rosmarinus officinalis L, Catharanthus roseus Linn., Azadirachta indica A. Juss and Moringa stenopetala Bac) against a panel of seven biofilm-forming MRSA. The leaves of the plants were extracted in organic solvents of varying polarity and the resultant crude extracts of respective medicinal plants were inspected for their antimicrobial activity by well diffusion technique. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of the plant extracts against MRSA were determined by the broth dilution method. Besides, an anti-biofilm assay of the most potent plant extract was also performed, after which its chemical constituents were delineated by combined Gas Chromatographic and Mass Spectroscopic profiling (GC-MS). The results revealed that, of the five plants, three species including M. stenopetala, R. officinalis, and O. lamifolium exhibited significant antibacterial activity. Organic solvents with high and medium polarity were excellent in extracting antimicrobials compared to nonpolar solvents. The broadest and highest rank of activity was observed in the crude ethanolic extract of M. stenopetala. Based on the MIC/MBC ratio, the crude ethanolic extract of M. stenopetala was determined to be bacteriostatic. Anti-biofilm assay showed that the extract of M. stenopetala fairly inhibited the growth of MRSA in the preformed biofilm matrix. The GC-MS analysis of M. stenopetala revealed the presence of twelve compounds with antimicrobial activity. The present study provides new insight into the development of novel drug leads to the management of MRSA.