Staffing crisis capacity: a different approach to healthcare resource allocation for a different type of scarce resource.

Severe staffing shortages have emerged as a prominent threat to maintaining usual standards of care during the COVID-2019 pandemic. In dire settings of crisis capacity, healthcare systems assume the ethical duty to maximise aggregate population-level benefit of existing resources. To this end, existing plans for rationing mechanical ventilators and intensive care unit beds in crisis capacity focus on selecting individual patients who are most likely to survive and prioritising these patients to receive scarce resources. However, staffing capacity is conceptually different from availability of these types of discrete resources, and the existing strategy of identifying and prioritising patients with the best prognosis cannot be readily adapted to fit this real-world scenario. We propose that two alternative approaches to staffing resource allocation offer a better conceptual fit: (1) prioritise the worst off: restrict access to acute care services and hospital admission for patients at relatively low clinical risk and (2) prioritise staff interventions with high near-term value: universally restrict selected interventions and treatments that require substantial staff time and/or energy but offer minimal near-term patient benefit. These strategies-while potentially resulting in care that deviates from usual standards-support the goal of maximising the aggregate benefit of scarce resources in crisis capacity settings triggered by staffing shortages. This ethical framework offers a foundation to support institutional leaders in developing operationalisable crisis capacity policies that promote fairness and support healthcare workers.

Conflicts of interest in clinical ethics consults.

Although there is wide agreement that ethics consults are at risk for conflicts of interest (COIs), ethics consultants (ECs) have limited guidance with regard to how to identify and approach COIs. We aim to address these concerns and provide practical guidance. We will define and consider four categories of COIs: consult type, team composition, dual clinical roles and other concerns. We will define and consider six actions available for ECs to take in response to COIs: no action, disclosure only, obtaining a second opinion, referring to another EC, referring to an institutional ethics committee or seeking an outside consult. We will then propose a points-based algorithm for ECs to use to determine the appropriate response to COI. Finally, we will discuss the strengths and limitations of our proposed algorithm.

No Need to Object: Ethical Obligations for Interprofessional Collaboration in Emergency Department Discharge Planning.

Emergency departments (EDs) serve a wide range of patient needs. A crucial aspect of safe and effective care in the ED is to appropriately transition patients to the next level of care. In most EDs, this disposition planning is done exclusively by physicians, which has the potential to result in unacceptable harm. A virtue ethics approach demonstrates the need for explicit inclusion of nurses in disposition planning. In utilizing this approach, it is necessary to examine four focal virtues as they relate to the work of disposition planning and the moral character of the nurse. The virtues of prudence, trustworthiness, vigilance, and courage show that interprofessional collaboration is needed during disposition planning to promote patient safety, facilitate interprofessional relationships, and prevent moral distress. The majority of literature on disposition planning is empirical in nature; this chapter adds a normative argument and a motive for policy reform.

The risk of development and progression of diabetic retinopathy in a group of ethnically diverse pregnant women with diabetes attending three regional Diabetic Eye Screening Programs in the UK.

BACKGROUND/OBJECTIVES: Currently, all pregnant women with diabetes are asked to attend screening at least twice during pregnancy, even if no retinopathy is detected in early pregnancy. We hypothesise that for women with no diabetic retinopathy in early pregnancy, the frequency of retinal screening may be safely reduced. SUBJECTS/METHODS: In this retrospective cohort study, data for 4718 pregnant women attending one of three UK Diabetic Eye Screening (DES) Programmes between July 2011 and October 2019 was extracted. The women's UK DES grades at 13 weeks gestation (early pregnancy) and 28 weeks gestation (late pregnancy) were recorded. Descriptive statistics were used to report baseline data. Ordered logistic regression was used to control for covariates, such as age, ethnicity, diabetes duration, and diabetes type. RESULTS: Of the women with grades recorded for both early and late pregnancy, a total of 3085 (65.39%) women had no retinopathy in early pregnancy, and 2306 (74.7%) of these women did not develop any retinopathy by 28 weeks. The number of women without retinopathy in early pregnancy who developed referable retinopathy was 14 (0.45%), none of whom required treatment. Diabetic Retinopathy in early pregnancy remained a significant predictor of DES grade in late pregnancy when covariates of Age, Ethnicity, and Diabetes Type were controlled for (P < 0.001). CONCLUSIONS: In summary, this study has demonstrated that the burden of managing diabetes for pregnant mothers may be safely reduced by limiting the number of diabetic eye screening appointments in women who have no retinal changes in early pregnancy. Screening of women with retinopathy in early pregnancy should continue in line with current UK guidance.

Predicting 1, 2 and 3 year emergent referable diabetic retinopathy and maculopathy using deep learning.

BACKGROUND: Predicting diabetic retinopathy (DR) progression could enable individualised screening with prompt referral for high-risk individuals for sight-saving treatment, whilst reducing screening burden for low-risk individuals. We developed and validated deep learning systems (DLS) that predict 1, 2 and 3 year emergent referable DR and maculopathy using risk factor characteristics (tabular DLS), colour fundal photographs (image DLS) or both (multimodal DLS). METHODS: From 162,339 development-set eyes from south-east London (UK) diabetic eye screening programme (DESP), 110,837 had eligible longitudinal data, with the remaining 51,502 used for pretraining. Internal and external (Birmingham DESP, UK) test datasets included 27,996, and 6928 eyes respectively. RESULTS: Internal multimodal DLS emergent referable DR, maculopathy or either area-under-the receiver operating characteristic (AUROC) were 0.95 (95% CI: 0.92-0.98), 0.84 (0.82-0.86), 0.85 (0.83-0.87) for 1 year, 0.92 (0.87-0.96), 0.84 (0.82-0.87), 0.85 (0.82-0.87) for 2 years, and 0.85 (0.80-0.90), 0.79 (0.76-0.82), 0.79 (0.76-0.82) for 3 years. External multimodal DLS emergent referable DR, maculopathy or either AUROC were 0.93 (0.88-0.97), 0.85 (0.80-0.89), 0.85 (0.76-0.85) for 1 year, 0.93 (0.89-0.97), 0.79 (0.74-0.84), 0.80 (0.76-0.85) for 2 years, and 0.91 (0.84-0.98), 0.79 (0.74-0.83), 0.79 (0.74-0.84) for 3 years. CONCLUSIONS: Multimodal and image DLS performance is significantly better than tabular DLS at all intervals. DLS accurately predict 1, 2 and 3 year emergent referable DR and referable maculopathy using colour fundal photographs, with additional risk factor characteristics conferring improvements in prognostic performance. Proposed DLS are a step towards individualised risk-based screening, whereby AI-assistance allows high-risk individuals to be closely monitored while reducing screening burden for low-risk individuals.

Diabetic retinopathy (DR) is a disease where the light-sensing layer at the back of the eye (retina) becomes damaged by raised blood sugar levels. It affects around one in three of the 463 million people with diabetes worldwide and is a leading cause of acquired vision loss in working-age adults. In this study, we developed computer-based models to predict when DR would reach a stage where vision could be threatened up to 3-years in the future. Our study shows that this system can accurately predict sight-threatening DR in patients with diabetes. This could mean fewer unnecessary visits for individuals at low-risk of DR progression, but closer monitoring and potentially earlier treatment for individuals at high-risk of DR progression, which could reduce the risk of vision loss.

People With Type 1 Diabetes of African Caribbean Ethnicity Are at Increased Risk of Developing Sight-Threatening Diabetic Retinopathy.

OBJECTIVE: There is limited information on the effect of ethnicity on the development of referable sight-threatening diabetic retinopathy (STDR) in people with type 1 diabetes. This study describes the risk factors for STDR in a diverse cohort of people with type 1 diabetes attending a regional diabetes eye screening service. RESEARCH DESIGN AND METHODS: Clinical and digital retinal imaging data from 1,876 people with type 1 diabetes (50% women, 72.1% Caucasian, 17.3% African Caribbean, 2.9% Asian, and 7.6% other) with no retinopathy at baseline, attending surveillance eye screening were reviewed. Referable STDR was defined as the presence of any moderate to severe nonproliferative or preproliferative diabetic retinopathy or proliferative diabetic retinopathy or maculopathy in either eye as per U.K. National Diabetic Eye Screening criteria. Median follow-up was 6 years. RESULTS: The median (interquartile range) age of the cohort was 29 (21, 41) years. Of the cohort of 1,876 people, 359 (19%) developed STDR. People who developed STDR had higher baseline HbA1c, raised systolic blood pressure (SBP), longer diabetes duration, and were more often of African Caribbean origin (24% vs. 15.6%; P < 0.05 for all). In multivariable Cox regression analyses, African Caribbean ethnicity (hazard ratio [HR] 1.39, 95% CI 1.09-1.78, P = 0.009), baseline SBP (HR 1.01, 95% CI 1.00-1.01, P = 0.033), and baseline HbA1c (HR 1.01, 95% CI 1.00-1.01, P = 0.0001) emerged as independent risk factors for STDR. CONCLUSIONS: We observed that people with type 1 diabetes of African Caribbean ethnicity are at significantly greater risk of STDR. Further research is required to understand the mechanisms that explain this novel observation.

Effect of socioeconomic deprivation as determined by the English deprivation deciles on the progression of diabetic retinopathy and maculopathy: a multivariate case-control analysis of 88 910 patients attending a South-East London diabetic eye screening service.

PURPOSE: To determine associations between deprivation using the Index of Multiple Deprivation (IMD and individual IMD subdomains) with incident referable diabetic retinopathy/maculopathy (termed rDR). METHODS: Anonymised demographic and screening data collected by the South-East London Diabetic Eye Screening Programme were extracted from September 2013 to December 2019. Multivariable Cox proportional models were used to explore the association between the IMD, IMD subdomains and rDR. RESULTS: From 118 508 people with diabetes who attended during the study period, 88 910 (75%) were eligible. The mean (± SD) age was 59.6 (±14.7) years; 53.94% were male, 52.58% identified as white, 94.28% had type 2 diabetes and the average duration of diabetes was 5.81 (±6.9) years; rDR occurred in 7113 patients (8.00%). Known risk factors of younger age, Black ethnicity, type 2 diabetes, more severe baseline DR and diabetes duration conferred a higher risk of incident rDR. After adjusting for these known risk factors, the multivariable analysis did not show a significant association between IMD (decile 1 vs decile 10) and rDR (HR: 1.08, 95% CI: 0.87 to 1.34, p=0.511). However, high deprivation (decile 1) in three IMD subdomains was associated with rDR, namely living environment (HR: 1.64, 95% CI: 1.12 to 2.41, p=0.011), education skills (HR: 1.64, 95% CI: 1.12 to 2.41, p=0.011) and income (HR: 1.19, 95% CI: 1.02 to 1.38, p=0.024). CONCLUSION: IMD subdomains allow for the detection of associations between aspects of deprivation and rDR, which may be missed when using the aggregate IMD. The generalisation of these findings outside the UK population requires corroboration internationally.

Functionality of Scarce Healthcare Resource Triage Teams During the COVID-19 Pandemic: A Multi-Institutional Simulation Study.

Plans for allocating scarce healthcare resources during the COVID-19 pandemic commonly involve the activation of institutional triage teams. These teams would be responsible for selecting patients who are most likely to survive to be prioritized to receive scarce resources. However, there is little empirical support for this approach. DESIGN: High-fidelity triage-team simulation study. SETTING: Healthcare institutions in Washington state. SUBJECTS: Triage teams, consisting of at least two senior clinicians and a bioethicist. INTERVENTIONS: Participants reviewed a limited amount of deidentified information for a diverse sample of critically ill patients. Teams then assigned each patient to one of five prioritization categories defined by likelihood of survival to hospital discharge. The process was refined based on observation and participant feedback after which a second phase of simulations was conducted. MEASUREMENTS AND MAIN RESULTS: Feasibility was assessed by the time required for teams to perform their task. Prognostic accuracy was assessed by comparing teams' prediction about likelihood of survival to hospital discharge with real-world discharge outcomes. Agreement between the teams on prognostic categorization was evaluated using kappa statistics. Eleven triage team simulations (eight in phase 1 and three in phase 2) were conducted from December 2020 to February 2021. Overall, teams reviewed a median of 23 patient cases in each session (interquartile range [IQR], 17-29) and spent a median of 102 seconds (IQR, 50-268) per case. The concordance between expected survival and real-world survival to discharge was 71% (IQR, 64-76%). The overall agreement between teams for placement of patients into prognostic categories was moderate (weighted kappa = 0.53). CONCLUSIONS: These findings support the potential feasibility, accuracy, and effectiveness of institutional triage teams informed by a limited set of patient information items as part of a strategy for allocating scarce resources in healthcare emergencies. Additional work is needed to refine the process and adapt it to local contexts.

Perspectives of Triage Team Members Participating in Statewide Triage Simulations for Scarce Resource Allocation During the COVID-19 Pandemic in Washington State.

Importance: The COVID-19 pandemic prompted health care institutions worldwide to develop plans for allocation of scarce resources in crisis capacity settings. These plans frequently rely on rapid deployment of institutional triage teams that would be responsible for prioritizing patients to receive scarce resources; however, little is known about how these teams function or how to support team members participating in this unique task. Objective: To identify themes illuminating triage team members' perspectives and experiences pertaining to the triage process. Design, Setting, and Participants: This qualitative study was conducted using inductive thematic analysis of observations of Washington state triage team simulations and semistructured interviews with participants during the COVID-19 pandemic from December 2020 to February 2021. Participants included clinician and ethicist triage team members. Data were analyzed from December 2020 through November 2021. Main Outcomes and Measures: Emergent themes describing the triage process and experience of triage team members. Results: Among 41 triage team members (mean [SD] age, 50.3 [11.4] years; 21 [51.2%] women) who participated in 12 simulations and 21 follow-up interviews, there were 5 Asian individuals (12.2%) and 35 White individuals (85.4%); most participants worked in urban hospital settings (32 individuals [78.0%]). Three interrelated themes emerged from qualitative analysis: (1) understanding the broader approach to resource allocation: participants strove to understand operational and ethical foundations of the triage process, which was necessary to appreciate their team's specific role; (2) contending with uncertainty: team members could find it difficult or feel irresponsible making consequential decisions based on limited clinical and contextual patient information, and they grappled with ethically ambiguous features of individual cases and of the triage process as a whole; and (3) transforming mindset: participants struggled to disentangle narrow determinations about patients' likelihood of survival to discharge from implicit biases and other ethically relevant factors, such as quality of life. They cited the team's open deliberative process, as well as practice and personal experience with triage as important in helping to reshape their usual cognitive approach to align with this unique task. Conclusions and Relevance: This study found that there were challenges in adapting clinical intuition and training to a distinctive role in the process of scarce resource allocation. These findings suggest that clinical experience, education in ethical and operational foundations of triage, and experiential training, such as triage simulations, may help prepare clinicians for this difficult role.

Patient Information Items Needed to Guide the Allocation of Scarce Life-Sustaining Resources: A Delphi Study of Multidisciplinary Experts.

OBJECTIVE: Plans for allocation of scarce life-sustaining resources during the coronavirus disease 2019 (COVID-19) pandemic often include triage teams, but operational details are lacking, including what patient information is needed to make triage decisions. METHODS: A Delphi study among Washington state disaster preparedness experts was performed to develop a list of patient information items needed for triage team decision-making during the COVID-19 pandemic. Experts proposed and rated their agreement with candidate information items during asynchronous Delphi rounds. Consensus was defined as ≥80% agreement. Qualitative analysis was used to describe considerations arising in this deliberation. A timed simulation was performed to evaluate feasibility of data collection from the electronic health record. RESULTS: Over 3 asynchronous Delphi rounds, 50 experts reached consensus on 24 patient information items, including patients' age, severe or end-stage comorbidities, the reason for and timing of admission, measures of acute respiratory failure, and clinical trajectory. Experts weighed complex considerations around how information items could support effective prognostication, consistency, accuracy, minimizing bias, and operationalizability of the triage process. Data collection took a median of 227 seconds (interquartile range = 205, 298) per patient. CONCLUSIONS: Experts achieved consensus on patient information items that were necessary and appropriate for informing triage teams during the COVID-19 pandemic.

A Practical Approach to Hospital Visitation During a Pandemic: Responding With Compassion to Unjustified Restrictions.

During the COVID-19 pandemic, evidence-based resources have been sought to support decision-making and strategically inform hospitals' policies, procedures, and practices. While greatly emphasizing protection, most guiding documents have neglected to support and protect the psychosocial needs of frontline health care workers and patients and their families during provision of palliative and end-of-life care. Consequently, the stage has been set for increased anxiety, moral distress, and moral injury and extreme moral hazard. A family-centered approach to care has been unilaterally relinquished to a secondary and nonessential role during the current crisis. This phenomenon violates a foundational public health principle, namely, to apply the least restrictive means to achieve good for the many. Instead, there has been widespread adoption of utilitarian and paternalistic approaches. In many cases the foundational principles of palliative care have also been neglected. No circumstance, even a global public health emergency, should ever cause health care providers to deny their ethical obligations and human commitment to compassion. The lack of responsive protocols for family visitation, particularly at the end of life, is an important gap in the current recommendations for pandemic triage and contingency planning. A stepwise approach to hospital visitation using a tiered, standardized process for responding to emerging clinical circumstances and individual patients' needs should be considered, following the principle of proportionality. A contingency plan, based on epidemiological data, is the best strategy to refocus health care ethics in practice now and for the future.

Prospective evaluation of an artificial intelligence-enabled algorithm for automated diabetic retinopathy screening of 30 000 patients.

BACKGROUND/AIMS: Human grading of digital images from diabetic retinopathy (DR) screening programmes represents a significant challenge, due to the increasing prevalence of diabetes. We evaluate the performance of an automated artificial intelligence (AI) algorithm to triage retinal images from the English Diabetic Eye Screening Programme (DESP) into test-positive/technical failure versus test-negative, using human grading following a standard national protocol as the reference standard. METHODS: Retinal images from 30 405 consecutive screening episodes from three English DESPs were manually graded following a standard national protocol and by an automated process with machine learning enabled software, EyeArt v2.1. Screening performance (sensitivity, specificity) and diagnostic accuracy (95% CIs) were determined using human grades as the reference standard. RESULTS: Sensitivity (95% CIs) of EyeArt was 95.7% (94.8% to 96.5%) for referable retinopathy (human graded ungradable, referable maculopathy, moderate-to-severe non-proliferative or proliferative). This comprises sensitivities of 98.3% (97.3% to 98.9%) for mild-to-moderate non-proliferative retinopathy with referable maculopathy, 100% (98.7%,100%) for moderate-to-severe non-proliferative retinopathy and 100% (97.9%,100%) for proliferative disease. EyeArt agreed with the human grade of no retinopathy (specificity) in 68% (67% to 69%), with a specificity of 54.0% (53.4% to 54.5%) when combined with non-referable retinopathy. CONCLUSION: The algorithm demonstrated safe levels of sensitivity for high-risk retinopathy in a real-world screening service, with specificity that could halve the workload for human graders. AI machine learning and deep learning algorithms such as this can provide clinically equivalent, rapid detection of retinopathy, particularly in settings where a trained workforce is unavailable or where large-scale and rapid results are needed.

Effects on alcohol consumption of announcing and implementing revised UK low-risk drinking guidelines: findings from an interrupted time series analysis.

BACKGROUND: In January 2016, the UK announced and began implementing revised guidelines for low-risk drinking of 14 units (112 g) per week for men and women. This was a reduction from the previous guidelines for men of 3-4 units (24-32 g) per day. There was no large-scale promotion of the revised guidelines beyond the initial media announcement. This paper evaluates the effect of announcing the revised guidelines on alcohol consumption among adults in England. METHODS: Data come from a monthly repeat cross-sectional survey of approximately 1700 adults living in private households in England collected between March 2014 and October 2017. The primary outcomes are change in level and time trend of participants' Alcohol Use Disorders Identification Test-Consumption (AUDIT-C) scores. RESULTS: In December 2015, the modelled average AUDIT-C score was 2.719 out of 12 and was decreasing by 0.003 each month. After January 2016, AUDIT-C scores increased immediately but non-significantly to 2.720 (ß=0.001, CI -0.079 to 0.099) and the trend changed significantly such that scores subsequently increased by 0.005 each month (ß=0.008, CI 0.001 to 0.015), equivalent to 0.5% of the population increasing their AUDIT-C score by 1 point each month. Secondary analyses indicated the change in trend began 7 months before the guideline announcement and that AUDIT-C scores reduced significantly but temporarily for 4 months after the announcement (ß=-0.087, CI -0.167 to 0.007). CONCLUSIONS: Announcing new UK drinking guidelines did not lead to a substantial or sustained reduction in drinking or a downturn in the long-term trend in alcohol consumption, but there was evidence of a temporary reduction in consumption.

Effect of Louisiana sweet crude oil on a Pacific coral, Pocillopora damicornis.

Recent oil spill responses such as the Deepwater Horizon event have underscored the need for crude oil ecotoxicological threshold data for shallow water corals to assist in natural resource damage assessments. We determined the toxicity of a mechanically agitated oil-seawater mixture (high-energy water-accommodated fraction, HEWAF) of a sweet crude oil on a branched stony coral, Pocillopora damicornis. We report the results of two experiments: a 96 h static renewal exposure experiment and a "pulse-chase" experiment of three short-term exposure durations followed by a recovery period in artificial seawater. Five endpoints were used to determine ecotoxicological values: 1) algal symbiont chlorophyll fluorescence, 2) a tissue regeneration assay and a visual health metric with three endpoints: 3) tissue integrity, 4) tissue color, and 5) polyp behavior. The sum of 50 entrained polycyclic aromatic hydrocarbons (tPAH50) was used as a proxy for oil exposure. For the 96 h exposure dose response experiment, dark-adapted maximum quantum yield (Fv/Fm) of the dinoflagellate symbionts was least affected by crude oil (EC50 = 913 µg/L tPAH50); light-adapted effective quantum yield (EQY) was more sensitive (EC50 =  428 µg/L tPAH50). In the health assessment, polyp behavior (EC50 = 27 µg/L tPAH50) was more sensitive than tissue integrity (EC50 = 806 µg/L tPAH50) or tissue color (EC50 = 926 µg/L tPAH50). Tissue regeneration proved to be a particularly sensitive measurement for toxicity effects (EC50 = 10 µg/L tPAH50). Short duration (6-24 h) exposures using 503 µg/L tPAH50 (average concentration) resulted in negative impacts to P. damicornis and its symbionts. Recovery of chlorophyll a fluorescence levels for 6-24 h oil exposures was observed in a few hours (Fv/Fm) to several days (EQY) following recovery in fresh seawater. The coral health assessments for tissue integrity and tissue color were not affected following short-term oil exposure durations, but the 96 h treatment duration resulted in significant decreases for both. A reduction in polyp behavior (extension) was observed for all treatment durations, with recovery observed for the short-term (6-24 h) exposures within 1-2 days following placement in fresh seawater. Wounded and intact fragments exposed to oil treatments were particularly sensitive, with significant delays observed in tissue regeneration. Estimating ecotoxicological values for P. damicornis exposed to crude oil HEWAFs provides a basis for natural resource damage assessments for oil spills in reef ecosystems. These data, when combined with ecotoxicological values for other coral reef species, will contribute to the development of species sensitivity models.

Spatial and temporal variability of ribotyping results at a small watershed in South Carolina.

The utility of library-based ribotyping methods for a very small study area was evaluated through comparison of local results to libraries with differing spatial and temporal scales. Ribotyping of Escherichia coli isolates was used to evaluate sources of fecal pollution at a coastal golf course in Beaufort County, South Carolina. Thirty-five E. coli isolates were obtained from water samples from a detention pond for testing against several local and regional libraries of known-source isolate patterns. A library of 92 E. coli ribotype patterns was created from wildlife feces obtained on the site. Additional libraries were available for comparison, including a library from Morgan Island, a small, geographically isolated area (including a monkey colony), and a library from ongoing statewide assessments. Seventeen (49%) of the unknown E. coli isolates matched isolates from raccoon and deer scat from the local library. Two isolates (6%) were matched with monkey sources from Morgan Island, and 13 (37%) were matched to raccoon, deer, and cows from the statewide assessment. Evaluation of repeated ribotyping analyses at the study area revealed evidence of temporal variability of potential sources in the local library. Only one of the isolates from the second year of fecal samples successfully matched with a fecal isolate from the previous year. The results from this study suggest that source identification results were variable both spatially and temporally, and that local, temporally specific libraries are most appropriate for library-based MST studies in small watersheds. Results also suggest that it will be difficult to employ adequate sample sizes to satisfactorily address unknown pattern variability.

Comparison of methods for the detection of coliphages in recreational water at two California, United States beaches.

Methods for detection of two fecal indicator viruses, F+ and somatic coliphages, were evaluated for application to recreational marine water. Marine water samples were collected during the summer of 2007 in Southern California, United States from transects along Avalon Beach (n=186 samples) and Doheny Beach (n=101 samples). Coliphage detection methods included EPA method 1601 - two-step enrichment (ENR), EPA method 1602 - single agar layer (SAL), and variations of ENR. Variations included comparison of two incubation times (overnight and 5-h incubation) and two final detection steps (lysis zone assay and a rapid latex agglutination assay). A greater number of samples were positive for somatic and F+ coliphages by ENR than by SAL (p<0.01). The standard ENR with overnight incubation and detection by lysis zone assay was the most sensitive method for the detection of F+ and somatic coliphages from marine water, although the method takes up to three days to obtain results. A rapid 5-h enrichment version of ENR also performed well, with more positive samples than SAL, and could be performed in roughly 24h. Latex agglutination-based detection methods require the least amount of time to perform, although the sensitivity was less than lysis zone-based detection methods. Rapid culture-based enrichment of coliphages in marine water may be possible by further optimizing culture-based methods for saline water conditions to generate higher viral titers than currently available, as well as increasing the sensitivity of latex agglutination detection methods.

Assessment of automated disease detection in diabetic retinopathy screening using two-field photography.

AIM: To assess the performance of automated disease detection in diabetic retinopathy screening using two field mydriatic photography. METHODS: Images from 8,271 sequential patient screening episodes from a South London diabetic retinopathy screening service were processed by the Medalytix iGrading™ automated grading system. For each screening episode macular-centred and disc-centred images of both eyes were acquired and independently graded according to the English national grading scheme. Where discrepancies were found between the automated result and original manual grade, internal and external arbitration was used to determine the final study grades. Two versions of the software were used: one that detected microaneurysms alone, and one that detected blot haemorrhages and exudates in addition to microaneurysms. Results for each version were calculated once using both fields and once using the macula-centred field alone. RESULTS: Of the 8,271 episodes, 346 (4.2%) were considered unassessable. Referable disease was detected in 587 episodes (7.1%). The sensitivity of the automated system for detecting unassessable images ranged from 97.4% to 99.1% depending on configuration. The sensitivity of the automated system for referable episodes ranged from 98.3% to 99.3%. All the episodes that included proliferative or pre-proliferative retinopathy were detected by the automated system regardless of configuration (192/192, 95% confidence interval 98.0% to 100%). If implemented as the first step in grading, the automated system would have reduced the manual grading effort by between 2,183 and 3,147 patient episodes (26.4% to 38.1%). CONCLUSION: Automated grading can safely reduce the workload of manual grading using two field, mydriatic photography in a routine screening service.

Improved detection and quantitation of norovirus from water.

Norovirus is associated commonly with human sewage and is responsible for numerous cases of waterborne and foodborne gastroenteritis every year. Assays using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) have been developed for norovirus, however, accurate detection and quantitation remain problematic owing to a lack of suitable positive controls. To improve enumeration of norovirus genomes from water, a synthetic norovirus genogroup II quantitation standard and competitive internal positive control were developed. The quantitation standard demonstrates identical amplification efficiency as wildtype norovirus and can be used as a viral surrogate in labs with restricted access to norovirus. The internal control quantifies sample inhibition, allowing for accurate quantitation of norovirus from complex environmental samples. Seawater samples spiked with sewage or bird guano were evaluated using the norovirus assay as part of a methods comparison study. Inhibition was detected in nine of 36 (25%) samples, two of which proved to be positive upon re-analysis. Results support the specificity of this assay for human-source (sewage) fecal contamination. Overall, use of this quantitation standard and internal control signify a great advance over traditional positive controls and suggest that molecular techniques for viral analysis could become standardized for routine water quality monitoring.

Assessment of environmental impacts of a colony of free-ranging rhesus monkeys (Macca mulatta) on Morgan Island, South Carolina.

Morgan Island, located within the ACE Basin National Estuarine Research Reserve in South Carolina, is home to the only free-ranging colony of rhesus monkeys (Macca mulatta) in the continental United States. The purpose of this study was to assess environmental impacts of the monkey colony on water quality in adjacent tidal creeks and on island vegetation. Three tidal creeks were sampled: Morgan Creek, adjacent to the monkey colony; Back Creek, on Morgan Island not adjacent to the colony; and Rock Creek, on a nearby island unoccupied by monkeys. Temperature, salinity, pH, dissolved oxygen, nutrients and fecal coliform bacteria were measured six times at three sites in each of these creeks, and vegetation change analysis was conducted in a geographic information system using satellite imagery. Results showed elevated fecal coliform concentrations in the Morgan Creek site immediately adjacent to the colony, though no samples exceeded the standard set for recreational water use. Ribotyping reconnaissance matched four Escherichia coli isolates from Morgan and Back Creeks to the monkeys, identifying the colony as one source of fecal coliform bacteria, though relative source loadings could not be quantified. Significant differences were not observed between ammonia or orthophosphate levels in Morgan Creek relative to the other creeks tested; and vegetation change analysis showed a 35% increase in canopy cover between 1979 and 1999. Overall, these results suggest that the rhesus colony's environmental impacts are localized and minimal. Results from this study provide baseline data on Morgan Island and may be useful in management decisions regarding the future of the monkey colony.