Hand Hygiene Education Components Among First-Year Nursing Students: A Cluster Randomized Clinical Trial.

Importance: Few studies have directly and objectively measured the individual and combined effects of multifaceted hand hygiene education programs. Objective: To evaluate the individual and combined immediate effects of an instructional video and hand scan images on handwashing quality, decontamination, and knowledge improvement. Design, Setting, and Participants: This cluster randomized clinical trial was conducted in June to July 2023 among first-year nursing students at a university in Hong Kong. The study used an intention-to-treat analysis. Intervention: Hand hygiene education sessions featuring an instructional video, hand scan images, or both. Main Outcomes and Measures: The primary outcome was the change in residue from fluorescent lotion remaining on participants' hands after handwashing before and after the intervention. The secondary outcomes included handwashing quality and knowledge of hand hygiene. Results: A total of 270 of 280 students (mean [SD] age, 19 [1] years; 182 [67.4%] female) participated in the trial (96.4% participation rate). Participants were randomized to a control group (66 participants), hand scan image group (68 participants), instructional video group (67 participants), and hand scan image with instructional video group (69 participants). All intervention groups had greater reductions in residue after the intervention compared with the control group, although none reached statistical significance (hand scan image group: 3.9 [95% CI, 2.0-5.8] percentage points; instructional video group: 4.8 [95% CI, 2.9-6.7] percentage points; hand scan image with instructional video: 3.5 [95% CI, 1.6-5.4] percentage points; control group: 3.2 [95% CI, 1.3-5.2] percentage points). The instructional video group showed a significant improvement in their handwashing performance, with a higher percentage of participants correctly performing all 7 steps compared with the control group (22.4% [95% CI, 13.1% to 31.6%] vs 1.5% [-7.9% to 10.9%]; P < .001). Hand scan images revealed that wrists, fingertips, and finger webs were the most commonly ignored areas in handwashing. Conclusions and Relevance: In this cluster randomized clinical trial of an education program for hand hygiene, a handwashing instructional video and hand scan images did not enhance the level of decontamination. The intervention group had improved handwashing techniques compared with the control group, a secondary outcome. Trial Registration: ClinicalTrials.gov Identifier: NCT05872581.

Factors associated with hand washing effectiveness: an institution-based observational study.

BACKGROUND: Few studies have investigated how the effectiveness of hand washing in removing hand contaminants is influenced by the performance and duration of each step involved. We conducted an observational study by recruiting participants from a university campus, with the aim to comprehensively evaluate how performance, duration and demographic factors influence hand washing effectiveness. METHODS: A total of 744 videos were collected from 664 participants in July-October 2022 and independently evaluated by two infection control experts through labelling videos for correct and incorrect performance of each step. The individual hand washing effectiveness was determined by quantifying the percentage of residual fluorescent gel on the dorsum and palm areas of each participant's hands. A logistic regression analysis was conducted to identify factors that were significantly associated with better hand washing effectiveness. An exposure-response relationship was constructed to identify optimal durations for each step. Approximately 2300 hand images were processed using advanced normalization algorithms and overlaid to visualize the areas with more fluorescence residuals after hand washing. RESULTS: Step 3 (rub between fingers) was the most frequently omitted step and step 4 (rub the dorsum of fingers) was the most frequently incorrectly performed step. After adjustment for covariates, sex, performance of step 4 and step 7 (rub wrists), rubbing hands during rinsing, and rinsing time were significantly associated with hand washing effectiveness. The optimal overall hand washing time was 31 s from step 1 to step 7, and 28 s from step 1 to step 6, with each step ideally lasting 4-5 s, except step 3. The palms of both hands had less fluorescence residuals than the dorsums. The areas where residuals most likely appeared were wrists, followed by finger tips, finger webs and thumbs. CONCLUSIONS: Performance and duration of some hand washing steps, sex and rinsing time were associated with hand washing effectiveness. The optimal duration might be applied to all seven steps to achieve the best decontamination results. Further studies are needed to refine hand hygiene standards and enhance compliance.

Learner attitudes towards a virtual microbiology simulation for pharmacy student education.

INTRODUCTION: Simulation for education has become popular, but much literature on this modality fails to critically examine the learner's experience, focusing instead on learning outcomes. Learner attitudes should be scrutinised and monitored to appraise a technology-enhanced learning experience as student perceived educational benefits of technology-enhanced learning is reported to be more important than the intrinsic characteristics of any particular medium or tool. This study sought to evaluate pharmacy students' attitudes toward a virtual microbiology simulation. METHODS: The virtual microbiology simulation (VUMIE) was compared with a traditional wet laboratory (lab) in a second-year integrated pharmacotherapeutics course for bachelor of pharmacy students. Data were collected using surveys deployed at baseline (pre-intervention), post-intervention (VUMIE or wet lab), and endpoint (post-interventions). Statistical and qualitative thematic analyses were performed. RESULTS: Learners found the simulation valuable, and outcomes suggest that it is possible for technology-enhanced learning activities to replace face-to-face instruction to some extent, which may be useful given the current challenges with in-person education resulting from COVID-19. More students reported a specific preference for the wet lab rather than VUMIE. CONCLUSIONS: Although technology-enhanced simulation can produce a similar learning experience to a traditional wet lab, this evidence is not sufficient to completely replace the traditional lab experience for clinical courses of study. Technology-enhanced simulation could be considered for just-in-time training before exposure to traditional lab activities, for specific skill acquisition using deliberate practice, and perhaps for standardised assessment for clinical microbiology education.

Personal and Household Hygiene Measures for Preventing Upper Respiratory Tract Infections among Children: A Cross-Sectional Survey of Parental Knowledge, Attitudes, and Practices.

Personal and household hygiene measures are important for preventing upper respiratory tract infections (URTIs) and other infectious diseases, including coronavirus disease 2019 (COVID-19). An online survey recruited 414 eligible parents in Hong Kong to study their hygiene knowledge, attitudes, and practices (KAPs) regarding the prevention of URTIs among their children. The average knowledge score was high (10.2/12.0), but some misconceptions were identified. The majority of the participants agreed that good personal hygiene (93.5%) and good environmental hygiene (92.8%) can prevent URTIs. The average score for hand hygiene practices was high (3.78/4.00), but only 56.8% of the parents always performed hand hygiene before touching their mouths, noses, or eyes. In terms of environmental hygiene, only some household items were disinfected with disinfectants (door handles in 69.8% of the households, toilet seats in 60.4% of the households, the floor in 42.8% of the households, dining chairs in 24.2% of the households, and dining tables in 20.5% of the households). A higher knowledge score was associated with parents having tertiary educational levels or above, working as healthcare professionals, living in private residential flats or staff quarters, or having household incomes of HKD 70,000 or above. The results of multiple regression analyses also indicated that parents who were healthcare professionals and with higher household income had a better parental knowledge of hygiene measures after adjusting the attitude score. For hand hygiene, parents who achieved higher attitude scores obtained higher practice scores. Under the fifth wave of the COVID-19 epidemic, there were some misconceptions regarding hygiene among parents. Any health promotion program should target parents regarding taking proper personal and household hygienic measures, especially for those who had relatively lower socio-economic status and/or from a non-healthcare background. Motivating attitudes toward hand hygiene can lead to better practices.

Acceptability and tolerability of alcohol-based hand hygiene products for elderly residents in long-term care: a crossover study.

Background: Hand hygiene is a critical component of infection control. Much of the focus on improving hand hygiene in healthcare settings has been directed towards healthcare worker compliance but its importance for patients, including those in long-term care facilities (LTCFs), is increasingly being recognised. Alcohol-based hand rub (ABHR) can lead to improved compliance. We aimed to determine acceptability and tolerability of two ABHRs for hand hygiene of elderly LTCF residents using a modified version of the WHO protocol. Methods: Thirty six elderly LTCF residents participated in this crossover study. A modified and translated (Chinese) version of the WHO protocol for evaluation of two or more ABHRs was used to determine product acceptability and tolerability for one gel (bottle with reclosable cap) and one foam (pump). During the 3-day testing period, participants were provided with their own portable bottle of ABHR. A research nurse objectively assessed the skin integrity of the hands at baseline and throughout the study. Skin moisture content was determined using a Scalar Moisture Checker Probe (Science Technology Resources, Ca, USA). Participants rated ABHR tolerability and acceptability using the WHO checklist at the end of each test period. Results: Both products passed the WHO criteria for acceptability and tolerability. The foam (86%) scored higher than the gel (51%) for ease of use possibly because some participants found the cap of the gel bottle difficult to open due to finger stiffness. No evidence of damage to skin integrity was observed. Overall, skin moisture content had improved by the end of the study. Residents preferred either of the test products to the liquid formulation currently in use by the LTCF. Conclusions: Overall, the elderly were willing to use ABHR for hand hygiene. Both products were well tolerated and preferred over the usual product provided by the LTCF. However, forgetfulness and difficulty rubbing the product over the hands due to finger stiffness posed a challenge for some residents. This could be overcome by using healthcare worker-assisted hand hygiene at specified times each day and prompts to serve as reminders to perform hand hygiene.

The public washroom - friend or foe? An observational study of washroom cleanliness combined with microbiological investigation of hand hygiene facilities.

Background: Many people use handwashing and hand-drying facilities in public washrooms under the impression that these amenities are hygienic. However, such facilities may be potential sites for the transmission of pathogenic bacteria. This study aimed to examine the hygiene facilities provided including handwashing and hand-drying facilities in public washrooms. Total bacterial counts and species identification were determined for hand-drying facilities. Antimicrobial susceptibilities were performed. Methods: The bacterial contamination levels of 55 public washrooms ranging in category from low class communities to high end establishments, were examined. The hygienic environment and facilities of the washrooms were analysed using an electronic checklist to facilitate immediate data entry. Pre-moistened sterile swabs were used to collect samples from areas around the outlet of paper towel dispensers, air outlet of air dryers, exit door handles and paper towels in the washrooms. Total bacterial counts were performed and isolates identified using matrix-assisted laser desorption ionisation time-of-flight mass spectrometry. Antimicrobial susceptibility was determined by disk diffusion. Results: The high and middle-income categories washrooms generally had cleaner facilities and environment followed by those in low categories. Fifty-two bacterial species were identified from the 55 investigated washrooms. Over 97% of the pathogenic Staphylococcus spp. tested were resistant to at least one first-line antimicrobial therapeutic agent, including penicillin, cefoxitin, erythromycin, co-trimoxazole, clindamycin and gentamicin, and 22.6% demonstrated co-resistance to at least three antimicrobial agents, with co-resistance to penicillin, erythromycin and clindamycin being the most common. Conclusion: Our findings suggest that hand-drying facilities in public washrooms can act as reservoirs of drug-resistant bacteria. The importance of frequent cleaning and maintenance of public washrooms to promote safe hand hygiene practices for the public are emphasised.

Reliability of N95 respirators for respiratory protection before, during, and after nursing procedures.

BACKGROUND: The adequate fit of an N95 respirator is important for health care workers to reduce the transmission of airborne infectious diseases in the clinical setting. This study aimed to evaluate whether adequately sealed N95 respirators may provide consistent protection for the wearer while performing nursing procedures. METHODS: Participants were a group of nursing students (N = 120). The best fitting respirator for these participants was identified from the 3 common models, 1860, 1860S, and 1870+ (3M), using the quantitative fit test (QNFT) method. Participants performed nursing procedures for 10-minute periods while wearing a backpack containing the portable aerosol spectrometers throughout the assessment to detect air particles inside the respirator. RESULTS: The average fit factor of the best fitting respirator worn by the participants dropped significantly after nursing procedures (184.85 vs 134.71) as detected by the QNFT. In addition, significant differences in particle concentration of different sizes (>0.3, >0.4, >1.0, and >4.0 µm) inside the respirator were detected by the portable aerosol spectrometers before, during, and after nursing procedures. CONCLUSIONS: Body movements during nursing procedures may increase the risk of face seal leakage. Further research, including the development of prototype devices for better respirator fit, is necessary to improve respiratory protection of users.

Anesthesia Lost in Translation: Perspective and Comprehension.

BACKGROUND: Care of non-English speaking patients poses a unique challenge to the anesthesiologist in the perioperative setting. Communication limitations can be frustrating to both the patient and provider, and at times can compromise the quality of care, resulting in health care disparities. An often overlooked, but critical component is the interaction between the anesthesia provider and the interpreter. The goal of our study was to identify misconceptions regarding anesthesia and determine common knowledge gaps amongst medical interpreters. METHODS: A survey inquiring about past perioperative experiences, level of training, and barriers to effective communication was sent to the Department of Interpreter Services (IS). Concurrently, a survey was sent to the Department of Anesthesia, about their experiences with interpreters in the perioperative setting. RESULTS: Our survey had 29 respondents from IS and 42 respondents from Anesthesia. 85% of interpreters had >5 years experience, but 96% denied having anesthesia specific training. Additionally, 42.5% of our interpreters felt that less than half of their patients were sufficiently literate to read and consent in their native language. Anesthesia providers were primarily concerned about the fidelity of the interpretation. CONCLUSIONS: Misunderstanding one another's field appears to play a significant role in the communication issues surrounding interpretation for anesthesia. Educating both departments may prove beneficial to resolving misconceptions, improving perioperative interactions and ultimately improving patient care. Based on the gathered information, a continuing education lecture was created by the Anesthesia Department in order to improve our interpreters' understanding of anesthesia, associated procedures and vocabulary.

Malnutrition in the elderly and its effects on bone health - A review.

This article aims to provide an overview of the prevalence, causes and risk factors associated with malnutrition in the elderly. It includes the clinical consequences and economic impact of malnutrition in the elderly and in particular the osteoporotic population. It encompasses the significance of dietary protein and its effects on bone health.

Awareness of tick-borne disease and compliance with using tick preventive products of dog owners in Hong Kong.

Tick-borne disease in dogs is common in South-east Asia and includes babesiosis and ehrlichiosis. These diseases can be largely prevented by compliant use of tick preventive products. This study investigated knowledge of ticks and tick-borne disease and use of tick preventive agents by a large sample of dog owners in Hong Kong. A total of 492 valid questionnaires were completed by owners attending veterinary practices, approached by researchers at common dog-walking areas, or targeted via local social media sites for pet owners. A high proportion of respondents were aware of tick-borne disease (79%) and this correlated well with use of preventive products. However, 18% of owners did not use any protection, mainly due to lack of knowledge of the risk of disease. Targeted advice stressing the importance of tick protection use and frequent follow-up at veterinary clinics could help reduce the risk of tick-borne disease. It would be beneficial if veterinarians provided training of frontline staff at the clinics to ensure they provide essential information to clients in an easily understandable format.

Goal-Oriented Anesthesia Week for MS III Students.

BACKGROUND: Third year medical students at our institution are required to complete a one-week rotation in anesthesia as part of their required twelve week surgery clerkship. During this constrained time, our aim was to provide students with a focused and goal-oriented preview of anesthesiology which would allow students going into various fields to have an appreciation of the field. CURRICULUM DESIGN: The one-week curriculum is a combination of lecture, simulation, operating room teaching and hands on experience aimed at providing students with some fundamentals of procedural skills and a knowledge base of anesthesia. To address the basic knowledge component, students are assigned a daily topic to review and discuss with their assigned resident mentor. From a procedural perspective, students gain basic airway management and IV skills during a half day in the Electroconvulsive Therapy (ECT) clinic where they primarily learn bag-mask ventilation and peripheral IV techniques. They additionally have a preoperative evaluation lecture and an airway simulation workshop. CURRICULUM EVALUATION: At the end of the rotation, students are required to fill out an online survey. Feedback from the survey was used to help further modify the goal-oriented curriculum. CONCLUSIONS: The results of the survey overall revealed students had an overwhelmingly positive experience during their week in the newly designed curriculum. Continued feedback will help us with further curriculum modifications as necessary.

A quasi-experimental study to determine the effects of a multifaceted educational intervention on hand hygiene compliance in a radiography unit.

BACKGROUND: Whilst numerous studies have investigated nurses' compliance with hand hygiene and use of alcohol-based hand rub (ABHR), limited attention has been paid to these issues in allied health staff. Reports have linked infections to breaches in infection control in the radiography unit (RU). With advances in medical imaging, a higher proportion of patients come into contact with RU staff increasing the need for good hand hygiene compliance. This study aimed to evaluate effectiveness on compliance of an intervention to improve awareness of hand hygiene in the RU of a district hospital. METHODS: A quasi-experimental study design including questionnaires assessing knowledge and attitudes of hand hygiene and direct observation of participants was used to evaluate an educational programme on hand hygiene of the RU of a large district hospital. All healthcare workers (HCW), comprising 76 radiographers, 17 nurses, and nine healthcare assistants (HCA), agreed to participate in the study. Of these, 85 completed the initial and 76 the post-test anonymous questionnaire. The hand hygiene compliance of all 102 HCW was observed over a 3-week period prior to and after the intervention. The 2-month intervention consisted of talks on hand hygiene and benefits of ABHR, provision of visual aids, wall-mounted ABHR dispensers, and personal bottles of ABHR. RESULTS: Before the intervention, overall hand hygiene compliance was low (28.9 %). Post-intervention, compliance with hand hygiene increased to 51.4 %. This improvement was significant for radiographers and HCA. Additionally, knowledge and attitudes improved in particular, understanding that ABHR can largely replace handwashing and there is a need to perform hand hygiene after environmental contact. The increased use of ABHR allowed HCW to feel they had enough time to perform hand hygiene. CONCLUSIONS: The educational intervention led to increased awareness of hand hygiene opportunities and better acceptance of ABHR use. The reduced time needed to perform hand rubbing and improved access to dispensers resulted in fewer missed opportunities. Although radiographers and other allied HCW make frequent contact with patients, these may be mistakenly construed as irrelevant with respect to healthcare associated infections. Stronger emphasis on hand hygiene compliance of these staff may help reduce infection risk.

Healthcare seeking behavior of patients with influenza like illness: comparison of the summer and winter influenza epidemics.

BACKGROUND: Influenza often causes winter and summer epidemics in subtropical regions, but few studies have investigated the difference in healthcare seeking behavior of patients with influenza-like illness (ILI) between these two epidemics. METHODS: Household telephone surveys were conducted using random digit dialing in Hong Kong during July-August 2014 and March-April 2015. One adult from each household was interviewed for ILI symptoms and associated healthcare seeking behaviour of themselves and one child in the household (if any), during the preceding 30 days. Healthcare seeking behavior of respondents with self-reported ILI was compared between summer and winter influenza. Logistic regression was used to explore the factors associated with healthcare seeking behavior. RESULTS: Among 516 and 539 adult respondents in the summer and winter surveys, 22.6 and 38.0 % reported ILI symptoms, and 40.9 and 46.8 % of them sought medical care, respectively. There was no significant difference in healthcare seeking behavior between the summer and winter epidemics, except a higher proportion of self-medication in summer in the adult respondents. Among 155 and 182 children reported by the adults in both surveys, the proportion of self-reported ILI was 32.9 and 40.1 % in the summer and winter surveys, respectively. Of these children, 47.1 and 56.2 % were brought for medical consultation in summer and winter, respectively. Women, adults with diabetes and those with symptoms of cough, shortness of breath, and runny nose were more likely to seek medical consultations for ILI symptoms. The factors associated with seeking medical consultations in children with ILI symptoms included being female, age under 10 years, and with symptoms of sore throat or vomiting. Those older than 60 years were less likely to self-medicate, whereas regular smokers and those with symptom of sore throat were more likely to do so. CONCLUSION: Healthcare seeking behavior of the general public was not significantly different between these two epidemics. However ILI was associated with increased healthcare utilization in both winter and summer epidemics in Hong Kong.

Tracking sources of Staphylococcus aureus hand contamination in food handlers by spa typing.

We aimed to identify the source of Staphylococcus aureus contaminating hands of food handlers. Nasal samples and direct fingertip imprints were collected on 2 occasions from food handlers and characterized to determine likely sources of hand contamination. Most hand contamination was attributable to nasal isolates of persistently colonized coworkers who had presumably contaminated the environment. Regular handwashing should be supplemented by effective environmental disinfection.

High levels of Staphylococcus aureus contamination in Chinese-style roast pork.

Chinese roasted pork has been implicated as a major source of food poisoning caused by Staphylococcus aureus. Establishing the source, either as contaminants from raw meat or from food handlers, could facilitate drafting more appropriate guidelines for better prevention of food poisoning. To determine the rate and source of staphylococcal contamination, roasted pork purchased from 50 sui-mei shops in Hong Kong was sampled for presence of S. aureus by enrichment and subsequent culture. Isolates were characterized for methicillin sensitivity, spa type, and presence of Panton-Valentine leukocidin (PVL) and staphylococcal enterotoxins (SEs). Methicillin-resistant isolates were confirmed by presence of mecA and SCCmec type and sensitivity to vancomycin investigated. S. aureus was isolated from 25 (50%) samples, with 3 yielding two colony types. Of the 28 isolates, 3 were resistant to cefoxitin, but only 2 were mecA positive and belonged to SCCmec type V. The mecA negative isolate also lacked mecC, but had a penicillin minimum inhibitory concentration of 10 mg/L. A livestock-associated spa type (t034) was only observed in one methicillin-sensitive strain, all other isolates appearing to be of human origin, with 30% belonging to t189. One isolate was PVL positive and five carried genes for classical SEs. The high rate of staphylococcal contamination observed was probably associated with food handlers, as the strains belonged to spa types previously reported in clinical and nasal carriage isolates. The presence of enterotoxins in 18% of isolates confirms the risk of food poisoning associated with this product and emphasizes the need for improved guidelines for handling after preparation. Use of refrigerated display areas should be considered.

Reduced vancomycin susceptibility in porcine ST9 MRSA isolates.

Porcine strains of livestock-associated methicillin resistant Staphylococcus aureus (LA-MRSA) have been recognized in many countries and have been shown to be able to cause human infection. Resistance to non-beta lactam antibiotics has been reported but non-susceptibility to vancomycin, which is known to occur in human MRSA, has so far not been observed in LA-MRSA. Such resistance is typically fairly low level involving changes in the cell wall thickness. The development of resistance is usually preceded by presence of a sub-population having an increased MIC, which is selected for by exposure to vancomycin. This study investigated vancomycin susceptibility of one hundred porcine MRSA isolates using three MIC methods including spiral gradient endpoint (SGE) technique which allows visualization of more resistant sub-populations. SGE revealed 16 strains with an MIC above 2.0 mg/L, of which 14 were determined to have MIC 4 mg/L by agar dilution (AD). SGE revealed a further two isolates with MIC < 2 mg/L had a sub-population >2 mg/L. In addition, trailing endpoints not reaching resistance were present in 26 isolates with MIC < 2 mg/L. Sequencing of the genes of the VraSR/GraSR two component systems of ten of the resistant strains for comparison with susceptible strains revealed changes, including the presence of stop codons, in vraS and graR, but these were not consistent in all isolates. Other genetic changes may contribute to vancomycin non-susceptibility and require investigation. As failure to respond to treatment has been reported in clinical isolates with MIC > 1.5 mg/L, the presence of vancomycin non-susceptibility in porcine isolates is of concern and further monitoring of LA-MRSA is essential.

Isolation of methicillin-resistant Staphylococcus aureus (MRSA) from retail meats in Hong Kong.

OBJECTIVES: The presence of methicillin-resistant Staphylococcus aureus (MRSA) on meat purchased from retail outlets may allow its spread to households and represents a risk for colonization and possibly infection of consumers. Improved isolation methods have indicated that more than 10% of samples are positive. We aimed to determine rates of MRSA contamination of meat samples, including comparison of fresh and frozen samples. We characterized isolates and determined their antibiotic susceptibility. METHODS: Samples of raw meats commonly consumed in Hong Kong were investigated for MRSA contamination using a double-enrichment isolation method. Isolates were characterized by antibiotic susceptibility testing, presence of mecA, SCCmec type, staphylococcal enterotoxins, Panton-Valentin leukocidin (PVL), and spa type. Differences in rates of MRSA contamination between meat types, rearing method, locations, sources, and fresh or frozen storage were compared. RESULTS: MRSA was recovered from 21.9% of pork samples (78/355), 6.8% chicken (31/455), and 4.4% of beef (17/380). Isolation was considerably higher from fresh pork (47%) than frozen (0.6%), whereas contamination rates in fresh (6%) and frozen (7%) chicken were similar. All strains were multidrug resistant. All contaminated fresh pork and most frozen chicken originated from China. Most isolates belonged to CC9, being SCCmec IVb and spa type t899 or closely related spa types, but one chicken sample yielded ST398. Five strains carried spa types associated with human isolates. The egc enterotoxin group was present in the majority of isolates, but PVL in only three from chicken. CONCLUSIONS: The predominance of t899 in isolates indicates that the primary source of contamination may be pig carcasses, previously demonstrated to frequently harbor CC9-positive MRSA in Hong Kong and China. The high rates of meat contamination suggest that improvements in food safety and personal hygiene guidelines may be advisable to reduce risk of spread of these MRSA strains in the community.

Rapid detection of vancomycin-non-susceptible Staphylococcus aureus using the spiral gradient endpoint technique.

OBJECTIVES: Several methods have been introduced for detection of vancomycin-non-susceptible Staphylococcus aureus [heterogeneous vancomycin-intermediate S. aureus (hVISA) and vancomycin-intermediate S. aureus (VISA)]. However, the limitations of these methods can delay appropriate therapy for the patient. This study evaluated the spiral gradient endpoint (SGE) technique for detection of hVISA/VISA. METHODS: The SGE method was evaluated for intra-batch, inter-batch and inter-observer reproducibility in comparison with MICs determined by agar dilution. Three media, Mueller-Hinton agar, brain heart infusion agar and brain heart infusion agar with 5% glucose, were evaluated. The SGE method was compared with agar dilution for correlation of MIC and susceptibility category using control strains, clinical isolates and induced vancomycin-non-susceptible strains. RESULTS: The SGE method had good reproducibility and there was excellent correlation of MICs generated by SGE using brain heart infusion agar with those by agar dilution (r(2) =0.950), with no difference in resistance categories generated by the two methods. All VISA isolates were correctly identified and the method allowed easy identification of hVISA by means of the trailing endpoint. CONCLUSIONS: SGE offers a simple, rapid and cost-effective alternative method for the detection of hVISA/VISA for the routine laboratory. Early recognition of vancomycin-non-susceptible strains can allow the change to appropriate antibiotics, resulting in potentially better patient outcomes.

Spiral gradient endpoint susceptibility testing: a fresh look at a neglected technique.

OBJECTIVES: Increasing antibiotic resistance and interest in matching antibiotic therapy with pharmacokinetic/pharmacodynamic characteristics of isolates has led to increasing demands for determination of MICs. This can lead to increased costs for the laboratory. The spiral gradient endpoint (SGE) technique, a low-cost method of MIC determination, was developed some years ago. Although the technique showed good correlation with reference methods, it was not widely employed, mainly due to the introduction of alternative methods. We have revisited this technique and evaluated it for the determination of MICs for fastidious organisms. METHODS: The SGE method was first optimized for fastidious organisms using Haemophilus influenzae. Intra-batch and inter-batch reproducibility was determined for H. influenzae, Streptococcus pneumoniae, Moraxella catarrhalis and Neisseria gonorrhoeae. The method was then evaluated by comparison of MICs for clinical isolates of these organisms determined by SGE with those determined with the reference method. RESULTS: Optimization of the technique resulted in a method with excellent reproducibility for all organisms tested [SD 0.10-0.337; coefficient of variation (CV) 8.59%-18.66%]. These SDs/CVs were lower than those of the reference methods (0.27-2.34; 31.0%-63.8%). There was excellent correlation of the MICs with the reference methods (0.908-0.930) and insignificant differences in numbers of strains in each resistance category, with no tendency for SGE to produce higher or lower MICs than the reference method (P > 0.05). CONCLUSIONS: SGE was shown to be reproducible and produced results that correlated well with standard techniques for fastidious organisms. The method offers a rapid, flexible, cost-effective alternative for smaller laboratories and for routine use in developing countries.