Methicillin Resistant Staphylococcus aureus in Pigs and Pig Breeders in Three Regions of Cameroon

The spread of antibiotic resistance, whether in the community or in the hospital, has recently become a major public health problem. Moreover, livestock seems to be a reservoir of resistant microorganisms such as porcine methicillin resistant Staphylococcus aureus (P-MRSA) whose carriage and transmission was mainly demonstrated in persons with occupational exposure to pigs. Much uncertainty remains about the public health implications of P-MRSA. To address concerns that exist regarding the zoonotic risk that pig carriers pose to breeders, the prevalence of P-MRSA in pigs and pig breeders was determined among 152 pig breeders in three regions of Cameroon. Materials and Method: Participants in this study came from Adamawa, Far North and Littoral regions of Cameroon. A total of 152 pig breeders or farm workers participated in this study. After having collected some social and cultural data with the aid of a questionnaire, nasal swabs were collected from pigs (n = 275) and their breeders using the standard collection procedures and placed in cooler containing cold accumulators. For each sample, microbiological assays were done as well as antibiotic susceptibility tests. Results: MRSA was isolated from 25 out of 275 pigs sampled (9.09%) and from 32 out of 152 (21.05%) pig breeders sampled;33 breeders (21.71%) were carriers of S. aureus including 32 MRSA and one MSSA. The prevalence of MRSA nasal carriage was 21.05% ± 6.48. A significant negative association between body protection and nasal carriage of MRSA (OR = 0.29, 95% CI [0.093;0.93];p = 0.04) was observed. In each region, similar strains of MRSA were isolated both in pigs and their breeders with the same antibiotic resistant profile. Conclusion: The prevalence of MRSA though not high compared to European countries warrants further research as data on this zoonosis is scarce in our context. As such, transmission of MRSA from pigs to pig breeders or vice-versa constitutes a real danger, and this relationship may be a starting point for MRSA contamination in the community. Moreover, proper use of body protections and antibiotic medications as recommended will be a better protective measure against nasal MRSA carriage.

What’s old is new again:Insights into diabetic foot microbiome

Diabetes is a chronic disease that is considered one of the most stubborn global health problems that continues to defy the efforts of scientists and physicians.The prevalence of diabetes in the global population continues to grow to alarming levels year after year,causing an increase in the incidence of diabetes complications and health care costs all over the world.One major complication of diabetes is the high susceptibility to infections especially in the lower limbs due to the immunocompromised state of diabetic patients,which is considered a definitive factor in all cases.Diabetic foot infections continue to be one of the most common infections in diabetic patients that are associated with a high risk of serious complications such as bone infection,limb amputations,and life-threatening systemic infections.In this review,we discussed the circumstances associated with the high risk of infection in diabetic patients as well as some of the most commonly isolated pathogens from diabetic foot infections and the related virulence behavior.In addition,we shed light on the different treatment strategies that aim at eradicating the infection.

Chemical analysis and antioxidant content of various propolis samples collected from different regions and their impact on antimicrobial activities

Objective: To assess the antioxidant content, antimicrobial and antioxidant activities of various propolis samples. Methods: Seven propolis samples were collected from different locations in Morocco, which are characterized by different plant predominant vegetations. The resin, wax and balsam of hydroalcoholic extract of propolis content were identified, and the antioxidant content was analyzed with the use of HPLC and colorimetric methods. The antioxidant activity was assessed by DPPH, ABTS.^+ and ferric reducing power assays. The antimicrobial activity was assessed against bacterial species, including methicillin resistant Staphylococcus aureus and Candida albicans, and expressed as the minimal inhibitory concentration. Results: The propolis samples showed significant variations in the chemical composition and in the antioxidant or antimicrobial activities even when the samples were collected from the same location. Propolis with high resin and low wax content had high level of antioxidant compounds, and strong antioxidant and antimicrobial activities. Gram-positive bacteria, especially, methicillin resistant Staphylococcus aureus were more sensitive to all propolis samples than Gram-negative bacteria and Candida albicans. Conclusions: The chemical composition and the antioxidant and antimicrobial activities of various propolis samples are different and rely on the geographic and plant origin of propolis collection. Propolis samples with low wax and high resin content might be more suitable to be used in future preclinical or clinical investigations.

Molecular Diversity of <i>Staphylococcus aureus</i>from the Nares of Hospital Personnel, HIV-Positive and Diabetes Mellitus Patients in Yaounde Cameroon

Nasal carriage of Staphylococcus aureus has been identified as a risk factor for the development of staphylococcal infections caused by endogenous colonizing strains. Information on the genotypic diversity of Staphylococcus aureus is relevant for managing epidemiological and clinical challenges resulting from the evolutionary differences of this bacterium. The objective of this study was to determine and compare the molecular diversity of Staphylococcus aureus isolates from three high-risk populations in Yaounde, Cameroon. Molecular analysis confirmed that 95% of 100 tested isolates were S. aureus. The mecA and Panton Valentine-Leukocidin (PVL) genes (lukS/F-PV) were detected in 37% (35/95) and 43% (41/95) of isolates respectively and 18% (17/95) of the isolates harboured both the mecA and lukS/F-PV genes. A mixed distribution of both methicillin sensitive S. aureus (MSSA)/PVL and methicillin resistant S. aureus (MRSA)/PVL strains were detected within the study population. Community associated MRSA accounted for 94% (33/35) of the isolates, further classified into allotypes SCCmec type IV 54% (19/35) and SCCmec type V 40% (14/35), while two isolates were hospital associated SCCmec type II strains. A majority of the isolates harboured a single aggressive gene regulator allele agr type I. Pulsed Field Gel Electrophoresis (PFGE) generated 18 pulsotypes that grouped isolates irrespective of the study population. Multilocus Sequence Typing (MLST) of 12 selected isolates was assigned to six pandemic clonal complexes (CC): CC5 (ST5), CC8 [ST8, (n = 3)], CC15 (ST 15), CC25 (ST 25), CC72 [ST72 (n = 2)] and CC121 [ST 121 (n = 2)] and three atypical sequence types ST 508, ST 699 (CC45) and ST 1289 (CC 88). The study population represents an important reservoir for MRSA, MRSA-PVL and MSSA-PVL which could serve as focal point for further dissemination bringing about significant clinical and epidemiological implications. The predominance of SCCmec IV and agr types in this setting warrants further investigation. Isolates were genetically diverse with MLST indicating that pandemic ST8 was predominant. Detection of atypical STs has provided an insight into the necessity for constant monitoring.

Antibiofilm activity of a-mangostin extracted from Garcinia mangostana L. against Staphylococcus aureus

Objective: To isolate a-mangostin(AMG) from the peels of mangosteen(Garcinia mangostana L.), grown in Vietnam, and to investigate antibiofilm activity of this compound against three Staphylococcus aureus(S. aureus) strains, one of which was methicillin-resistant S. aureus(MRSA) and the other two strains were methicillinsensitive S. aureus(MSSA).Methods: AMG in n-hexane fraction was isolated on a silica gel column and chemically analyzed by HPLC and NMR. The antibiofilm activity of this compound was investigated by using a 96-well plate model for the formation of biofilms. Biofilm biomass was quantified using crystal violet. The viability of cells was observed under confocal microscopy using LIVE/DEAD Bac Light stains. Biofilm composition was determined using specific chemical and enzyme tests for polysaccharide, protein and DNA. Membranedamaging activity was assayed by measuring the hemolysis of human red blood cells in presence of AMG.Results: The results indicated that the isolated AMG, with a purity that exceeded 98%,had minimal inhibitory concentrations in the range of 4.6–9.2 mmol/L for the three strains tested. Interestingly, the MSSA strains were more sensitive to AMG than the MRSA strain. Minimal bactericidal concentrations were 2-fold higher than the minimal inhibitory concentration values for the three strains, indicating that AMG was a bactericidal compound. AMG also prevented biofilm formation effectively, albeit that again the MRSA strain was the most resistant. Interestingly, biofilms of the MRSA strain contained protein as a main component of the extracellular matrix, whereas this was polysaccharide in the MSSA strains. This might relate to the resistance of the MRSA 252 strain to AMG.Assays using human red blood cells indicated that AMG caused significant membrane damage with 50% of cell lysis occurred at concentration of about 36 mmol/L.Conclusions: Our results provide evidence that the isolated AMG has inhibitory activity against biofilm formation by S. aureus, including MRSA. Thus, isolated AMG proposes a high potential to develop a novel phytopharmaceutical for the treatment of MRSA.

Gene typing and antibiotic resistance of methicillin- resistant Staphylococcus aureus isolated from lower respiratory tract at two hospitals in Shanghai

Objective To study the genotyping characteristics and antibiotic resistance of methicillin-resistant Staphylococcus aureus(MRSA)isolated from lower respiratory tract at 2 different level hospitals in Shanghai.Methods The subjects included 155 patients at Ruijin Hospital and Tongren Hospital between January 2013 and June 2014,including 108 males and 47 females,with a mean age