Human-associated methicillin-resistant Staphylococcus aureus from a subtropical recreational marine beach.

Reports of Staphylococcus aureus including methicillin-resistant S. aureus (MRSA) detected in marine environments have occurred since the early 1990 s. This investigation sought to isolate and characterize S. aureus from marine waters and sand at a subtropical recreational beach, with and without bathers present, in order to investigate possible sources and to identify the risks to bathers of exposure to these organisms. During 40 days over 17 months, 1,001 water and 36 intertidal sand samples were collected by either bathers or investigators at a subtropical recreational beach. Methicillin-sensitive S. aureus (MSSA) and MRSA were isolated and identified using selective growth media and an organism-specific molecular marker. Antimicrobial susceptibility, staphylococcal cassette chromosome mec (SCCmec) type, pulsed-field gel electrophoresis (PFGE) pattern, multi-locus sequence type (MLST), and staphylococcal protein A (spa) type were characterized for all MRSA. S. aureus was isolated from 248 (37 %) bather nearby water samples at a concentration range of <2-780 colony forming units per ml, 102 (31 %) ambient water samples at a concentration range of <2-260 colony forming units per ml, and 9 (25 %) sand samples. Within the sand environment, S. aureus was isolated more often from above the intertidal zone than from intermittently wet or inundated sand. A total of 1334 MSSA were isolated from 37 sampling days and 22 MRSA were isolated from ten sampling days. Seventeen of the 22 MRSA were identified by PFGE as the community-associated MRSA USA300. MRSA isolates were all SCCmec type IVa, encompassed five spa types (t008, t064, t622, t688, and t723), two MLST types (ST8 and ST5), and 21 of 22 isolates carried the genes for Panton-Valentine leukocidin. There was a correlation (r = 0.45; p = 0.05) between the daily average number of bathers and S. aureus in the water; however, no association between exposure to S. aureus in these waters and reported illness was found. This report supports the concept that humans are a potential direct source for S. aureus in marine waters.

Influence of social networking websites on medical school and residency selection process.

BACKGROUND: Social networking (SN) has become ubiquitous in modern culture. The potential consequences of revealing personal information through SN websites are not fully understood. OBJECTIVE: To assess familiarity with, usage of, and attitudes towards, SN websites by admissions offices at US medical schools and residency programmes. METHODS: A 26-question survey was distributed in autumn 2009 to 130 US medical school admissions officers and 4926 residency programme directors accredited by the Accreditation Council for Graduate Medical Education. RESULTS: A total of 600 surveys were completed, with 46 (8%) respondents who self-identified as reviewing only medical school applications, 511 (85%) who reported reviewing residency programme applications and 43 (7%) who reported reviewing both. 90/600 (15%) medical schools or programmes maintain profiles on SN websites and 381/600 (64%) respondents reported being somewhat or very familiar with searching individual profiles on SN websites. While a minority of medical schools and residency programmes routinely use SN websites in the selection process (53/600; 9%), more than half of respondents felt that unprofessional information on applicants' SN websites could compromise their admission into medical school or residency (315/600; 53%). CONCLUSIONS: SN websites will affect selection of medical students and residents. Formal guidelines for professional behaviour on SN websites might help applicants avoid unforeseen bias in the selection process.

Use of mobile learning module improves skills in chest tube insertion.

BACKGROUND: Just-In-Time Learning is a concept increasingly applied to medical education, and its efficacy must be evaluated. MATERIALS AND METHODS: A 3-minute video on chest tube insertion was produced. Consenting participants were assigned to either the video group, which viewed the video on an Apple® iPod Touch immediately before chest tube insertion, or the control group, which received no instruction. Every participant filled out a questionnaire regarding prior chest tube experience. A trained clinician observed participants insert a chest tube on the TraumaMan® task simulator, and assessed performance using a 14-item skills checklist. RESULTS: Overall, 128 healthcare trainees participated, with 50% in the video group. Participants included residents (34.4%, n = 44), medical students (32.8%, n = 42), and U.S. Army Forward Surgical Team members (32.8%, n = 42). Sixty-nine percent of all participants responded that they had never placed a chest tube, but 7% had placed more than 20. Only 25% of the participants had previously used TraumaMan®. Subjects who viewed the video scored better on the skills checklist than the control group (11.09 ± 3.09 versus 7.17 ± 3.56, P < 0.001, Cohen's D = 1.16). Medical students (9.33 ± 2.65 versus 4.52 ± 3.64, P < 0.001), Forward Surgical Team members (10.07 ± 2.52 versus 8.57 ± 3.22, P < 0.001), anesthesia residents (8.25 ± 2.56 versus 5.9 ± 2.23, P = 0.017), and subjects who had placed fewer than 10 chest tubes (9.7 ± 3 versus 6.6 ± 3.9, P < 0.001) performed significantly better with the video. CONCLUSIONS: The procedural animation video is an effective medium for teaching procedural skills. Embedding the video on a mobile device, and allowing trainees to access it immediately before chest tube insertion, may enhance and standardize surgical education for civilians and military personnel.

Mobile learning module improves knowledge of medical shock for forward surgical team members.

OBJECTIVE: Acute trauma care is characterized by dynamic situations that require adequate preparation to ensure success for military health professionals. The use of mobile learning in this environment can provide a solution that standardizes education and replaces traditional didactic lectures. METHODS: A comparative evaluation with a pre-post test design regarding medical shock was delivered via either a didactic lecture or a mobile learning video module to U.S. Army Forward Surgical Team (FST) members. Participants completed a pretest, were randomly assigned to treatment group by FST, and then completed the post-test and scenario assessment. RESULTS: One-hundred and thirteen FST members participated with 53 in the mobile learning group and 60 in the lecture group (control). The percent mean score for the mobile learning group increased from 43.6 to 70 from pretest to post-test, with a scenario mean score of M = 56.2. The percent mean score for the control group increased from 41.5 to 72.5, with a scenario mean score of M = 59.7. The two-way analysis of variance mean score difference was 26.4 for the mobile learning group and 31.0 for the control, F = 2.18, (p = 0.14). CONCLUSIONS: Mobile learning modules, coupled with a structured assessment, have the potential to improve educational experiences in civilian and military settings.

Shedding of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus from adult and pediatric bathers in marine waters.

BACKGROUND: Staphylococcus aureus including methicillin resistant S. aureus, MRSA, are human colonizing bacteria that commonly cause opportunistic infections primarily involving the skin in otherwise healthy individuals. These infections have been linked to close contact and sharing of common facilities such as locker rooms, schools and prisons Waterborne exposure and transmission routes have not been traditionally associated with S. aureus infections. Coastal marine waters and beaches used for recreation are potential locations for the combination of high numbers of people with close contact and therefore could contribute to the exposure to and infection by these organisms. The primary aim of this study was to evaluate the amount and characteristics of the shedding of methicillin sensitive S. aureus, MSSA and MRSA by human bathers in marine waters. RESULTS: Nasal cultures were collected from bathers, and water samples were collected from two sets of pools designed to isolate and quantify MSSA and MRSA shed by adults and toddlers during exposure to marine water. A combination of selective growth media and biochemical and polymerase chain reaction analysis was used to identify and perform limited characterization of the S. aureus isolated from the water and the participants. Twelve of 15 MRSA isolates collected from the water had identical genetic characteristics as the organisms isolated from the participants exposed to that water while the remaining 3 MRSA were without matching nasal isolates from participants. The amount of S. aureus shed per person corresponded to 105 to 106 CFU per person per 15-minute bathing period, with 15 to 20% of this quantity testing positive for MRSA. CONCLUSIONS: This is the first report of a comparison of human colonizing organisms with bacteria from human exposed marine water attempting to confirm that participants shed their own colonizing MSSA and MRSA into their bathing milieu. These findings clearly demonstrate that adults and toddlers shed their colonizing organisms into marine waters and therefore can be sources of potentially pathogenic S. aureus and MRSA in recreational marine waters. Additional research is needed to evaluate recreational beaches and marine waters as potential exposure and transmission pathways for MRSA.

Daily measures of microbes and human health at a non-point source marine beach.

Studies evaluating the relationship between microbes and human health at non-point source beaches are necessary for establishing criteria which would protect public health while minimizing economic burdens. The objective of this study was to evaluate water quality and daily cumulative health effects (gastrointestinal, skin, and respiratory illnesses) for bathers at a non-point source subtropical marine recreational beach in order to better understand the inter-relationships between these factors and hence improve monitoring and pollution prevention techniques. Daily composite samples were collected, during the Oceans and Human Health Beach Exposure Assessment and Characterization Health Epidemiologic Study conducted in Miami (Florida, USA) at a non-point source beach, and analyzed for several pathogens, microbial source tracking markers, indicator microbes, and environmental parameters. Analysis demonstrated that rainfall and tide were more influential, when compared to other environmental factors and source tracking markers, in determining the presence of both indicator microbes and pathogens. Antecedent rainfall and F+ coliphage detection in water should be further assessed to confirm their possible association with skin and gastrointestinal (GI) illness outcomes, respectively. The results of this research illustrate the potential complexity of beach systems characterized by non-point sources, and how more novel and comprehensive approaches are needed to assess beach water quality for the purpose of protecting bather health.

Ten-year review of BMW Accident Research Program-investigated cases.

OBJECTIVE: Over the past 10 years, the BMW Accident Research Program (ARP) has investigated how and why occupants are injured in motor vehicle crashes by reconstructing the crash. This research discusses the 2006-2017 ARP case study methodology and comprehensively describes the cases investigated over the past decade. METHODS: Accident research program cases are selected according to emerging trends and issues identified by BMW. Driver interviews, inspection approvals, police reports, and medical records are obtained. ARP case investigations involve a multidisciplinary team of engineers, automobile crash experts, and a trauma team. For each case, the team reconstructs the crash and explores in detail the crash characteristics, injury outcomes, as well as case significance and countermeasures that could have prevented the crash or mitigated the severity of the crash or injuries sustained. RESULTS: The ARP investigated 476 BMW-involved crashes between 2006 and 2017 in the United States. The majority of the crash investigations involved a frontal crash (55%). The other crash types included rollover (17%), nearside (13%), farside (9%), and rear crashes (5%). Crash characteristics such as roadway departure (26%), fatality (8%), elderly (>65 years old) occupant crashes (7%), crashes preceded by a medical event (4%), and crashes preceded by the driver falling asleep at the wheel (4%) are particularly informative in regards to advanced driver assistance systems (ADAS) role. The distribution of Maximum Abbreviated Injury Scale (MAIS) scores for the occupants were AIS 1 (23%), AIS 2 (33%), AIS 3 (10%), AIS 4 (4%), and AIS 5 + (7%); 16% of crashes involved uninjured occupants and 7% included no injury information. CONCLUSIONS: In-depth case reviews of moderate and severe crashes remain vital to determine emerging trends, patterns of crash injury, and analysis of driver assistance systems and other factors with potential to prevent the crash or limit severity.

Just-in-time learning is effective in helping first responders manage weapons of mass destruction events.

BACKGROUND: Chemical, biologic, radiologic, nuclear, and explosive (CBRNE) incidents require specialized training. The low frequency of these events leads to significant skill decay among first responders. To address skill decay and lack of experience with these high-impact events, educational modules were developed for mobile devices to provide just-in-time training to first responders en route to a CBRNE event. This study assessed the efficacy and usability of the mobile training. METHODS: Ninety first responders were randomized to a control or an intervention group. All participants completed a pretest to measure knowledge of CBRNE topics. The intervention group then viewed personal protective equipment and weapons of mass destruction field management videos as an overview. Both groups were briefed on a disaster scenario (chemical nerve agent, radiologic, or explosives) requiring them to triage, assess, and manage a patient. Intervention group participants watched a mobile training video corresponding to the scenario. The control group did not receive prescenario video training. Observers rated participant performance in each scenario. After completing the scenarios, all participants answered a cognitive posttest. Those in the intervention group also answered a questionnaire on their impressions of the training. RESULTS: The intervention group outperformed the control group in the explosives and chemical nerve agent scenarios; the differences were statistically significant (explosives, mean of 26.32 for intervention and 22.85 for control, p < 0.01; nerve agent, mean of 23.14 for intervention and 16.61 for control, p < 0.01). There was no statistically significant difference between the groups in the radiologic scenario (mean, 12.7 for intervention and 11.8 for control; p = 0.51). The change in pretest to posttest cognitive scores was significantly higher in the intervention group than in the control group (t = 3.28, p < 0.05). CONCLUSION: Mobile just-in-time training improved first-responder knowledge of CBRNE events and is an effective tool in helping first responders manage simulated explosive and chemical agent scenarios. LEVEL OF EVIDENCE: Therapeutic/care management study, level II.

Knowledge and usability of a trauma training system for general surgery residents.

BACKGROUND: Resident work-hour restrictions challenge educators to supplement residents' surgical education. We evaluated a computer-based trauma surgery system's ability to increase residents' surgical knowledge. METHODS: Modules on thoracic and abdominal surgical approaches were evaluated. Surgical residents with 1 or more years of experience completed the pretest, an interactive module, the post-test, and a usability survey. RESULTS: Fifteen participants completed both modules. Thoracic module pretest and post-test scores were 56 ± 11 (mean ± standard deviation) and 90 ± 10, respectively (P < .0001). Mean abdominal module scores were 48 ± 20 and 85 ± 14, respectively (P < .0001). The usability survey showed that 87% of participants would use these modules to supplement their trauma training, 93% could easily distinguish anatomic detail, and 100% thought that procedures were shown clearly. CONCLUSIONS: This novel computer-based trauma education training system improved residents' knowledge of anatomy, surgical incisions, exposures, and technique. As innovative didactic tools arise in postgraduate medical education, it is crucial to document their effects on educational processes, learning satisfaction, and knowledge outcomes.

Identifying pitfalls in chest tube insertion: improving teaching and performance.

OBJECTIVE: Chest tube thoracostomies are common surgical procedures, but little is known about how practitioners learn the skill. This study evaluates the frequency with which correctly performed tasks are executed by subjects during chest tube thoracostomies. DESIGN: In this prospective study, we developed a mobile-learning module, containing stepwise multimedia guidance on chest tube insertion. Next, we developed and tested a 14-item checklist, modeled after key skills in the module. Participants, defined as "novice" (fewer than 10 chest tubes placed) or "expert" (10 or more placed), were assigned to either the video or control group. A trained clinician used the checklist to rate participants while they inserted a chest tube on a TraumaMan simulator. SETTING: University of Miami, Miller School of Medicine, a tertiary care academic institution. PARTICIPANTS: Current medical students, residents, and the United States Army Forward Surgical Team members rotating through the institution. One hundred twenty-eight subjects entered and finished the study. RESULTS: One hundred twenty-eight subjects enrolled in the study; 86 (67%) were residents or US Army Forward Surgical Team members, 66 (77%) were novices, and 20 (23%) were experts. Novices most frequently connected the tube to suction (91%), adequately dissected the soft tissue (82%), and scrubbed or anesthetized appropriately (80%). They least frequently completed full finger sweeps (33%), avoided the neurovascular bundle (35%), and performed a controlled pleural puncture (39%). Comparing the novice video group with the novice control group, the video group was more likely to correctly perform a finger sweep (42%, p<0.001) and clamp the distal end of the chest tube (42%, p<0.001). Of all the steps, experts least frequently completed full finger sweeps (70%) and avoided the neurovascular bundle (75%). Comparing the expert video group with the expert control group, the video group was more likely to correctly perform finger sweeps, the incision, and clamping the distal chest tube (20%, p = not significant). CONCLUSIONS: Avoiding the neurovascular bundle, controlled pleural entry, and finger sweeps are most often performed incorrectly among novices. This information can help instructors to emphasize key didactic steps, possibly easing trainees' learning curve.

The BEACHES Study: health effects and exposures from non-point source microbial contaminants in subtropical recreational marine waters.

BACKGROUND: Microbial water-quality indicators, in high concentrations in sewage, are used to determine whether water is safe for recreational purposes. Recently, the use of these indicators to regulate recreational water bodies, particularly in sub/tropical recreational marine waters without known sources of sewage, has been questioned. The objectives of this study were to evaluate the risk to humans from exposure to subtropical recreational marine waters with no known point source, and the possible relationship between microbe densities and reported symptoms in human subjects with random-exposure assignment and intensive individual microbial monitoring in this environment. METHODS: A total of 1303 adult regular bathers were randomly assigned to bather and non-bather groups, with subsequent follow-up for reported illness, in conjunction with extensive environmental sampling of indicator organisms (enterococci). RESULTS: Bathers were 1.76 times more likely to report gastrointestinal illness [95% confidence interval (CI) 0.94-3.30; P = 0.07]; 4.46 times more likely to report acute febrile respiratory illness (95% CI 0.99-20.90; P = 0.051) and 5.91 times more likely to report a skin illness (95% CI 2.76-12.63; P < 0.0001) relative to non-bathers. Evidence of a dose-response relationship was found between skin illnesses and increasing enterococci exposure among bathers [1.46 times (95% CI 0.97-2.21; P = 0.07) per increasing log(10) unit of enterococci exposure], but not for gastrointestinal or respiratory illnesses. CONCLUSIONS: This study indicated that bathers may be at increased risk of several illnesses relative to non-bathers, even in the absence of any known source of domestic sewage impacting the recreational marine waters. There was no dose-response relationship between gastroenteritis and increasing exposure to enterococci, even though many current water-monitoring standards use gastroenteritis as the major outcome illness.

Traditional and molecular analyses for fecal indicator bacteria in non-point source subtropical recreational marine waters.

The use of enterococci as the primary fecal indicator bacteria (FIB) for the determination of recreational water safety has been questioned, particularly in sub/tropical marine waters without known point sources of sewage. Alternative FIB (such as the Bacteroidales group) and alternative measurement methods (such as rapid molecular testing) have been proposed to supplement or replace current marine water quality testing methods which require culturing enterococci. Moreover, environmental parameters have also been proposed to supplement current monitoring programs. The objective of this study was to evaluate the health risks to humans from exposure to subtropical recreational marine waters with no known point source. The study reported symptoms between one set of human subjects randomly assigned to marine water exposure with intensive environmental monitoring compared with other subjects who did not have exposure. In addition, illness outcomes among the exposed bathers were compared to levels of traditional and alternative FIB (as measured by culture-based and molecular-based methods), and compared to easily measured environmental parameters. Results demonstrated an increase in self-reported gastrointestinal, respiratory and skin illnesses among bathers vs. non-bathers. Among the bathers, a dose-response relationship by logistic regression modeling was observed for skin illness, where illness was positively related to enterococci enumeration by membrane filtration (odds ratio = 1.46 [95% confidence interval = 0.97-2.21] per increasing log10 unit of enterococci exposure) and positively related to 24 h antecedent rain fall (1.04 [1.01-1.07] per increasing millimeters of rain). Acute febrile respiratory illness was inversely related to water temperature (0.74 [0.56-0.98] per increasing degree of water temperature). There were no significant dose-response relationships between report of human illness and any of the other FIB or environmental measures. Therefore, for non-point source subtropical recreational marine waters, this study suggests that humans may be at increased risk of reported illness, and that the currently recommended and investigational FIB may not track gastrointestinal illness under these conditions; the relationship between other human illness and environmental measures is less clear.

Quantitative evaluation of enterococci and Bacteroidales released by adults and toddlers in marine water.

Traditionally, the use of enterococci has been recommended as the fecal indicator bacteria of choice for testing marine recreational water quality, and prior studies have shown that bathers shed large numbers of enterococci into the water. The current study expands upon prior research by evaluating shedding from both toddlers and adults, and by the expansion of measurements to include enterococci shedding via three different methods (membrane filter (MF), chromogenic substrate (CS), and quantitative polymerase chain reaction (qPCR)) and shedding of alternative fecal indicator bacteria (Bacteroidales human markers UCD and HF8 via qPCR). Two sets of experiments were conducted. The first experiment consisted of two groups of 10 adults who bathed together in a large pool. The second study consisted of 14 toddlers who bathed individually in a small pool which allowed for sand recovery. Sand recovery was used to estimate the amount of sand transported on the bodies of toddlers and to estimate the number of fecal indicator bacteria released from this sand. The numbers of estimated enterococci shed per adult ranged from 1.8 x 10(4) to 2.8 x 10(6) CFU, from 1.9 x 10(3) to 4.5 x 10(6) MPN, and from 3.8 x 10(5) to 5.5 x 10(6) GEU based on the MF, CS, and qPCR methods, respectively. The estimated numbers of Bacteroidales human markers ranged from 1.8 x 10(4) to 1.3 x 10(6) for UCD, and ranged from the below detection limit to 1.6 x 10(5) for HF8. The estimated amount of sand transported per toddler (n=14) into the water column after sand exposure was 8+/-6g on average. When normalizing the numbers of enterococci shed from toddlers via sand by the 3.9 body surface area ratio, the differences between toddlers and adults were insignificant. Contributions of sands to the total enterococci (MF) shed per toddler was 3.7+/-4.4% on average. Although shedding via beach sand may contribute a small fraction of the microbial load during initial bathing, it may have a significant role if bathers go to water repetitively after sand exposure.