BackgroundManuka honey originates from the manuka tree (Leptospermum scoparium) and its antimicrobial effect has been attributed to a property referred to as Unique Manuka Factor that is absent in other types of honey. Antibacterial activity of Manuka honey has been documented for several bacterial pathogens, however there is no information on Clostridium difficile, an important nosocomial pathogen. In this study we investigated susceptibility of C. difficile to Manuka honey and whether the activity is bactericidal or bacteriostatic.MethodsThree C. difficile strains were subjected to the broth dilution method to determine minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) for Manuka honey. The agar well diffusion method was also used to investigate sensitivity of the C. difficile strains to Manuka honey.ResultsThe MIC values of the three C. difficile strains were the same (6.25% v/v). Similarly, MBC values of the three C. difficile strains were the same (6.25% v/v). The activity of Manuka honey against all three C. difficile strains was bactericidal. A dose–response relationship was observed between the concentrations of Manuka honey and zones of inhibition formed by the C. difficile strains, in which increasing concentrations of Manuka honey resulted in increasing size of zone of inhibition formed. Maximum zone of inhibition was observed at 50% (v/v) Manuka honey and the growth inhibition persisted over 7 days.ConclusionC. difficile is appreciably susceptible to Manuka honey and this may offer an effective way of treating infections caused by the organism.

BackgroundBiofilm bacteria are relatively more resistant to antibiotics. The escalating trend of antibiotic resistance higlights the need for evaluating alternative potential therapeutic agents with antibacterial properties. The use of honey for treating microbial infections dates back to ancient times, though antimicrobial properties of Manuka honey was discovered recently. The aim of this study was to demonstrate biofilm formation of specific Clostridium difficile strains and evaluate susceptibility of the biofilm to Manuka honey.MethodsThree C. difficile strains were used in the study including the ATCC 9689 strain, a ribotype 027 strain and a ribotype 106 strain. Each test strain was grown in sterile microtitre plates and incubated at 37°C for 24 and 48 hours in an anaerobic cabinet to allow formation of adherent growth (biofilm) on the walls of the wells. The effect of Manuka honey on the biofilms formed was investigated at varying concentrations of 1-50% (w/v) of Manuka honey.ResultsThe three C. difficile strains tested formed biofilms after 24 hours with the ribotype 027 strain producing the most extensive growth. There was no significant difference (p > 0.05) found between the amount of biofilms formed after 24 and 48 hours of incubation for each of the three C. difficile strains. A dose–response relationship between concentration of Manuka honey and biofilm formation was observed for all the test strains, and the optimum Manuka honey activity occurred at 40-50% (v/v).ConclusionManuka honey has antibacterial properties capable of inhibiting in vitro biofilm formed by C. difficile.

IntroductionDue to an upsurge in antibiotic-resistant infections and lack of therapeutic options, new approaches are needed for treatment. Honey may be one such potential therapeutic option. We investigated the susceptibility of hospital acquired pathogens to four honeys from Wisconsin, United States, and then determined if the antibacterial effect of each honey against these pathogens is primarily due to the high sugar content.MethodsThirteen pathogens including: four Clostridium difficile, two Methicillin-resistant Staphylococcus aureus, two Pseudomonas aeruginosa, one Methicillin-Susceptible Staphylococcus aureus, two Vancomycin-resistance Enterococcus, one Enterococcus faecalis and one Klebsiella pneumoniae were exposed to 1-50% (w/v) four Wisconsin honeys and Artificial honey to determine their minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the broth dilution method.ResultsBuckwheat honey predominantly exhibited a bactericidal mode of action against the tested pathogens, and this varied with each pathogen. C. difficile isolates were more sensitive to the Wisconsin buckwheat honey as compared to the other pathogens. Artificial honey at 50% (w/v) failed to kill any of the pathogens. The high sugar content of Wisconsin buckwheat honey is not the only factor responsible for its bactericidal activity.ConclusionWisconsin buckwheat honey has the potential to be an important addition to therapeutic armamentarium against resistant pathogens and should be investigated further.

Introduction Preoperative nasal decolonization of surgical patients with nasal povidone-iodine (PI) has potential to eliminate pathogenic organisms responsible for surgical site infections. However, data on implementation of PI for quality improvement in clinical practice is limited. The purpose of this study was to evaluate the implementation feasibility, fidelity and acceptability of intranasal PI solution application by surgical nurses using the Integrated Promoting Action on Research Implementation in Health Services (i-PARIHS) conceptual framework. Materials and methods Using the i-PARIHS framework to frame questions and guide interview content areas, we conducted 15 semi-structured interviews of pre- and post-operative care nurses in two facilities. We analyzed the data using deductive content analysis to evaluate nurses’ experience and perceptions on preoperative intranasal PI solution decolonization implementation. Open coding was used to analyze the data to ensure all relevant information was captured. Results Each facility adopted a different quality improvement implementation strategy. The mode of facilitation, training, and educational materials provided to the nurses varied by facility. Barriers identified included lack of effective communication, insufficient information and lack of systematic implementation protocol. Action taken to mitigate some of the barriers included a collaboration between the study team and nurses to develop a systematic written protocol. The training assisted nurses to systematically follow the implementation protocol smoothly to ensure PI administration compliance, and to meet the goal of the facilities. Nurses’ observations and feedback showed that PI did not cause any adverse effects on patients. Conclusions We found that PI implementation was feasible and acceptable by nurses and could be extended to other facilities. However further studies are required to ensure standardization of PI application.

Introduction The composition of the nasal microbiota in surgical patients in the context of general anesthesia and nasal povidone-iodine decolonization is unknown. The purpose of this quality improvement study was to determine: (i) if general anesthesia is associated with changes in the nasal microbiota of surgery patients and (ii) if preoperative intranasal povidone-iodine decolonization is associated with changes in the nasal microbiota of surgery patients. Materials and methods One hundred and fifty-one ambulatory patients presenting for surgery were enrolled in a quality improvement study by convenience sampling. Pre- and post-surgery nasal samples were collected from patients in the no intranasal decolonization group (control group, n = 54). Pre-decolonization nasal samples were collected from the preoperative intranasal povidone-iodine decolonization group (povidone-iodine group, n = 97). Intranasal povidone-iodine was administered immediately prior to surgery and continued for 20 minutes before patients proceeded for surgery. Post-nasal samples were then collected. General anesthesia was administered to both groups. DNA from the samples was extracted for 16S rRNA sequencing on an Illumina MiSeq. Results In the control group, there was no evidence of change in bacterial diversity between pre- and post-surgery samples. In the povidone-iodine group, nasal bacterial diversity was greater in post-surgery, relative to pre-surgery (Shannon’s Diversity Index (P = 0.038), Chao’s richness estimate (P = 0.02) and Inverse Simpson index (P = 0.027). Among all the genera, only the relative abundance of the genus Staphylococcus trended towards a decrease in patients after application (FDR adjusted P = 0.06). Abundant genera common to both povidone-iodine and control groups included Staphylococcus, Bradyrhizobium, Corynebacterium, Dolosigranulum, Lactobacillus, and Moraxella. Conclusions We found general anesthesia was not associated with changes in the nasal microbiota. Povidone-iodine treatment was associated with nasal microbial diversity and decreased abundance of Staphylococcus. Future studies should examine the nasal microbiota structure and function longitudinally in surgical patients receiving intranasal povidone-iodine.