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We introduce a discrete mathematical model for the mechanical behaviour of a planar slice of human corneal tissue, in equilibrium under the action of physiological intraocular pressure (IOP). The model considers a regular (two-dimensional) network of structural elements mimicking a discrete number of parallel collagen lamellae connected by proteoglycan-based chemical bonds (crosslinks). Since the thickness of each collagen lamella is small compared to the overall corneal thickness, we upscale the discrete force balance into a continuum system of partial differential equations and deduce the corresponding macroscopic stress tensor and strain energy function for the micro-structured corneal tissue. We demonstrate that, for physiological values of the IOP, the predictions of the discrete model converge to those of the continuum model. We use the continuum model to simulate the progression of the degenerative disease known as keratoconus, characterized by a localized bulging of the corneal shell. We assign a spatial distribution of damage (i.e. reduction of the stiffness) to the mechanical properties of the structural elements and predict the resulting macroscopic shape of the cornea, showing that a large reduction in the element stiffness results in substantial corneal thinning and a significant increase in the curvature of both the anterior and posterior surfaces.
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PURPOSE: Accurate prediction of hernia occurrence is vital for surgical decision-making and patient management, particularly in colorectal surgery patients. While a hernia prediction model has been developed, its performance in external populations remain to be investigated. This study aims to validate the existing model on an external dataset of patients who underwent colorectal surgery. METHODS: The "Penn Hernia Calculator" model was externally validated using the Hughes Abdominal Repair Trial (HART) data, a randomized trial comparing colorectal cancer surgery closure techniques. The data encompassed demographics, comorbidities, and surgical specifics. Patients without complete follow-up were omitted. Model performance was assessed using key metrics, including area under the curve (AUC-ROC and AUC-PR) and Brier score. Reporting followed the TRIPOD consensus. RESULTS: An external international dataset consisting of 802 colorectal surgery patients were identified, of which 674 patients with up to 2 years follow-up were included. Average patient age was 68 years, with 63.8% male. The average BMI was 28.1. Prevalence of diabetes, hypertension, and smoking were 15.7%, 16.3%, and 36.5%, respectively. Additionally, 7.9% of patients had a previous hernia. The most common operation types were low anterior resection (35.3%) and right hemicolectomy (34.4%). Hernia were observed in 24% of cases by 2-year follow-up. The external validation model revealed an AUC-ROC of 0.66, AUC-PR of 0.72, and a Brier score of 0.2. CONCLUSION: The hernia prediction model demonstrated moderate performance in the external validation. Its potential generalizability, specifically in those undergoing colorectal surgery, may suggest utility in identifying and managing high-risk hernia candidates.
Subject(s)
Colorectal Neoplasms , Incisional Hernia , Aged , Female , Humans , Male , Abdomen/surgery , Colorectal Neoplasms/surgery , Herniorrhaphy/methods , Incisional Hernia/etiology , Incisional Hernia/surgery , Prognosis , Retrospective Studies , Randomized Controlled Trials as TopicABSTRACT
BACKGROUND: We developed a gap analysis that examines the role of brain-computer interfaces (BCI) in patients with disorders of consciousness (DoC), focusing on their assessment, establishment of communication, and engagement with their environment. METHODS: The Curing Coma Campaign convened a Coma Science work group that included 16 clinicians and neuroscientists with expertise in DoC. The work group met online biweekly and performed a gap analysis of the primary question. RESULTS: We outline a roadmap for assessing BCI readiness in patients with DoC and for advancing the use of BCI devices in patients with DoC. Additionally, we discuss preliminary studies that inform development of BCI solutions for communication and assessment of readiness for use of BCIs in DoC study participants. Special emphasis is placed on the challenges posed by the complex pathophysiologies caused by heterogeneous brain injuries and their impact on neuronal signaling. The differences between one-way and two-way communication are specifically considered. Possible implanted and noninvasive BCI solutions for acute and chronic DoC in adult and pediatric populations are also addressed. CONCLUSIONS: We identify clinical and technical gaps hindering the use of BCI in patients with DoC in each of these contexts and provide a roadmap for research aimed at improving communication for adults and children with DoC, spanning the clinical spectrum from intensive care unit to chronic care.
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Fescue toxicosis (FT) is produced by an ergot alkaloid (i.e., ergovaline [EV])-producing fungus residing in toxic fescue plants. Associations between EV, decreased weight gain and ruminal volatile fatty acids are unclear. Feces, rumen fluid, and blood were collected from 12 steers that grazed non-toxic (NT) or toxic (E +) fescue for 28 days. The E + group exhibited decreased propionate (P), increased acetate (A), and increased ruminal A:P ratio, with similar trends in feces. Plasma GASP-1 (G-Protein-Coupled-Receptor-Associated-Sorting-Protein), a myostatin inhibitor, decreased (day 14) only in E + steers. Ergovaline was present only in E + ruminal fluid and peaked on day 14. The lower ruminal propionate and higher A:P ratio might contribute to FT while reduced GASP-1 might be a new mechanism linked to E + -related weight gain reduction. Day 14 ergovaline zenith likely reflects ruminal adaptations favoring EV breakdown and its presence only in rumen points to local, rather than systemic effects.
Subject(s)
Festuca , Propionates , Animals , Propionates/toxicity , Ergotamines , Festuca/microbiology , Fatty Acids, Volatile , Weight Gain , Animal Feed/analysisABSTRACT
Objective.Surface electromyography measurements of the Hoffmann (H-) reflex are essential in a wide range of neuroscientific and clinical applications. One promising emerging therapeutic application is H-reflex operant conditioning, whereby a person is trained to modulate the H-reflex, with generalized beneficial effects on sensorimotor function in chronic neuromuscular disorders. Both traditional diagnostic and novel realtime therapeutic applications rely on accurate definitions of the H-reflex and M-wave temporal bounds, which currently depend on expert case-by-case judgment. The current study automates such judgments.Approach.Our novel wavelet-based algorithm automatically determines temporal extent and amplitude of the human soleus H-reflex and M-wave. In each of 20 participants, the algorithm was trained on data from a preliminary 3 or 4 min recruitment-curve measurement. Output was evaluated on parametric fits to subsequent sessions' recruitment curves (92 curves across all participants) and on the conditioning protocol's subsequent baseline trials (â¼1200 per participant) performed nearHmax. Results were compared against the original temporal bounds estimated at the time, and against retrospective estimates made by an expert 6 years later.Main results.Automatic bounds agreed well with manual estimates: 95% lay within ±2.5 ms. The resulting H-reflex magnitude estimates showed excellent agreement (97.5% average across participants) between automatic and retrospective bounds regarding which trials would be considered successful for operant conditioning. Recruitment-curve parameters also agreed well between automatic and manual methods: 95% of the automatic estimates of the current required to elicitHmaxfell within±1.4%of the retrospective estimate; for the 'threshold' current that produced an M-wave 10% of maximum, this value was±3.5%.Significance.Such dependable automation of M-wave and H-reflex definition should make both established and emerging H-reflex protocols considerably less vulnerable to inter-personnel variability and human error, increasing translational potential.
Subject(s)
H-Reflex , Muscle, Skeletal , Humans , Retrospective Studies , Electromyography , Muscle, Skeletal/physiology , H-Reflex/physiology , Peripheral Nerves , Electric StimulationABSTRACT
Executive attention impairments are a persistent and debilitating consequence of traumatic brain injury (TBI). To make headway towards treating and predicting outcomes following heterogeneous TBI, cognitive impairment specific pathophysiology first needs to be characterized. In a prospective observational study, we measured EEG during the attention network test aimed at detecting alerting, orienting, executive attention and processing speed. The sample (N = 110) of subjects aged 18-86 included those with and without traumatic brain injury: n = 27, complicated mild TBI; n = 5, moderate TBI; n = 10, severe TBI; n = 63, non-brain-injured controls. Subjects with TBI had impairments in processing speed and executive attention. Electrophysiological markers of executive attention processing in the midline frontal regions reveal that, as a group, those with TBI and elderly non-brain-injured controls have reduced responses. We also note that those with TBI and elderly controls have responses that are similar for both low and high-demand trials. In subjects with moderate-severe TBI, reductions in frontal cortical activation and performance profiles are both similar to that of controls who are â¼4 to 7 years older. Our specific observations of frontal response reductions in subjects with TBI and in older adults is consistent with the suggested role of the anterior forebrain mesocircuit as underlying cognitive impairments. Our results provide novel correlative data linking specific pathophysiological mechanisms underlying domain-specific cognitive deficits following TBI and with normal aging. Collectively, our findings provide biomarkers that may serve to track therapeutic interventions and guide development of targeted therapeutics following brain injuries.
Subject(s)
Brain Injuries, Traumatic , Executive Function , Healthy Aging , Aged , Humans , Aging , Biomarkers , Brain Injuries , Executive Function/physiology , Neuropsychological TestsABSTRACT
Background and Objectives: Following brain injury, clinical assessments of residual and emerging cognitive function are difficult and fraught with errors. In adults, recent American Academy of Neurology (AAN) practice guidelines recommend objective neuroimaging and neurophysiologic measures to support diagnosis. Equivalent measures are lacking in pediatrics-an especially great challenge due to the combined heterogeneity of both brain injury and pediatric development. Therefore, we aim to establish quantitative, clinically practicable measures of cognitive function following pediatric brain injury. Methods: Participants with and without brain injury were aged 8-18 years, clinically classified according to cognitive recovery state: N = 8 in disorders of consciousness (DoC), N = 7 in confusional state, N = 19 cognitively impaired, and N = 13 typically developing uninjured controls. We prospectively measured electroencephalographic markers of sensory processing and attention in an auditory oddball paradigm, and of covert movement attempts in a command-following paradigm. Results: In 3 participants with DoC, EEG markers of active attempted command following revealed cognitive function that clinical assessment had failed to detect. These same 3 individuals could also be distinguished from the rest of their group by 2 event-related potentials that correlate with sensory processing and orienting attention in the oddball paradigm. Considered across the whole participant group, magnitudes of these 2 ERP markers significantly increased as cognitive recovery progressed (ANOVA: each p < 0.001); viewed jointly, the 2 ERP markers cleanly delineated the 4 cognitive states. Discussion: Despite heterogeneity of brain injuries and brain development, our objective EEG markers reflected cognitive recovery independent of motor function. Two of these markers required no active participation. Together, they allowed us to identify 3 individuals who meet the criteria for cognitive-motor dissociation. To diagnose, prognose, and track cognitive recovery accurately, such markers should be used in pediatrics.
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The Evoked Potential Operant Conditioning System (EPOCS) is a software tool that implements protocols for operantly conditioning stimulus-triggered muscle responses in people with neuromuscular disorders, which in turn can improve sensorimotor function when applied appropriately. EPOCS monitors the state of specific target muscles-e.g., from surface electromyography (EMG) while standing, or from gait cycle measurements while walking on a treadmill-and automatically triggers calibrated stimulation when pre-defined conditions are met. It provides two forms of feedback that enable a person to learn to modulate the targeted pathway's excitability. First, it continuously monitors ongoing EMG activity in the target muscle, guiding the person to produce a consistent level of activity suitable for conditioning. Second, it provides immediate feedback of the response size following each stimulation and indicates whether it has reached the target value. To illustrate its use, this article describes a protocol through which a person can learn to decrease the size of the Hoffmann reflex-the electrically-elicited analog of the spinal stretch reflex-in the soleus muscle. Down-conditioning this pathway's excitability can improve walking in people with spastic gait due to incomplete spinal cord injury. The article demonstrates how to set up the equipment; how to place stimulating and recording electrodes; and how to use the free software to optimize electrode placement, measure the recruitment curve of direct motor and reflex responses, measure the response without operant conditioning, condition the reflex, and analyze the resulting data. It illustrates how the reflex changes over multiple sessions and how walking improves. It also discusses how the system can be applied to other kinds of evoked responses and to other kinds of stimulation, e.g., motor evoked potentials to transcranial magnetic stimulation; how it can address various clinical problems; and how it can support research studies of sensorimotor function in health and disease.
Subject(s)
Neuromuscular Diseases , Spinal Cord Injuries , Chronic Disease , Conditioning, Operant/physiology , Electromyography , Evoked Potentials , H-Reflex/physiology , HumansABSTRACT
Background and Objectives: Following severe brain injury, up to 16% of adults showing no clinical signs of cognitive function nonetheless have preserved cognitive capacities detectable via neuroimaging and neurophysiology; this has been designated cognitive-motor dissociation (CMD). Pediatric medicine lacks both practice guidelines for identifying covert cognition and epidemiologic data regarding CMD prevalence. Methods: We applied a diverse battery of neuroimaging and neurophysiologic tests to evaluate 2 adolescents (aged 15 and 18 years) who had shown no clinical evidence of preserved cognitive function following brain injury at age 9 and 13 years, respectively. Clinical evaluations were consistent with minimally conscious state (minus) and vegetative state, respectively. Results: Both participants' EEG, and 1 participant's fMRI, provided evidence that they could understand commands and make consistent voluntary decisions to follow them. Both participants' EEG demonstrated larger-than-expected responses to auditory stimuli and intact semantic processing of words in context. Discussion: These converging lines of evidence lead us to conclude that both participants had preserved cognitive function dissociated from their motor output. Throughout the 5+ years since injury, communication attempts and therapy had remained uninformed by such objective evidence of their cognitive abilities. Proper diagnosis of CMD is an ethical imperative. Children with covert cognition reflect a vulnerable and isolated population; the methods outlined here provide a first step in identifying such persons to advance efforts to alleviate their condition.
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Extreme environments present medical and occupational challenges that extend beyond generic resuscitation, to formulating bespoke diagnoses and prognoses and embarking on management pathways rarely encountered in civilian practice. Pathophysiological complexity and clinical uncertainty call for military physicians of all kinds to balance intuition with pragmatism, adapting according to the predominant patterns of care required. In an era of smaller operational footprints and less concentrated clinical experience, proposals aimed at improving the systematic care of Service Personnel incapacitated at environmental extremes must not be lost to corporate memory. These general issues are explored in the particular context of thermal stress and metabolic disruption. Specific focus is given to the accounts of military physicians who served on large-scale deployments into the heat of Iraq and Kuwait (Operation TELIC) and Oman (Exercise SAIF SAREEA). Generalisable insights into the enduring character of military medicine and future clinical requirements result.
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PURPOSE: Heat stress exacerbates post-exercise hypotension (PEH) and cardiovascular disturbances from elevated body temperature may contribute to exertion-related incapacity. Mast cell degranulation and muscle mass are possible modifiers, though these hypotheses lack practical evidence. This study had three aims: (1) to characterise pre-post-responses in histamine and mast cell tryptase (MCT), (2) to investigate relationships between whole body muscle mass (WBMM) and changes in blood pressure post-marathon, (3) to identify any differences in incapacitated runners. METHODS: 24 recreational runners were recruited and successfully completed the 2019 Brighton Marathon (COMPLETION). WBMM was measured at baseline. A further eight participants were recruited from incapacitated runners (COLLAPSE). Histamine, MCT, blood pressure, heart rate, body temperature and echocardiographic measures were taken before and after exercise (COMPLETION) and upon incapacitation (COLLAPSE). RESULTS: In completion, MCT increased by nearly 50% from baseline (p = 0.0049), whereas histamine and body temperature did not vary (p > 0.946). Systolic (SBP), diastolic (DBP) and mean (MAP) arterial blood pressures and systemic vascular resistance (SVR) declined (p < 0.019). WBMM negatively correlated with Δ SBP (r = - 0.43, p = 0.046). For collapse versus completion, there were significant elevations in MCT (1.77 ± 0.25 µg/L vs 1.18 ± 0.43 µg/L, p = 0.001) and body temperature (39.8 ± 1.3 °C vs 36.2 ± 0.8 °C, p < 0.0001) with a non-significant rise in histamine (9.6 ± 17.9 µg/L vs 13.7 ± 33.9 µg/L, p = 0.107) and significantly lower MAP, DBP and SVR (p < 0.033). CONCLUSION: These data support the hypothesis that mast cell degranulation is a vasodilatory mechanism underlying PEH and exercise associated collapse. The magnitude of PEH is inversely proportional to the muscle mass and enhanced by concomitant body heating.
Subject(s)
Histamine/metabolism , Marathon Running , Mast Cells/enzymology , Post-Exercise Hypotension/diagnostic imaging , Post-Exercise Hypotension/metabolism , Tryptases/metabolism , Adult , Biomarkers , Blood Pressure Determination , Body Composition , Body Temperature , Case-Control Studies , Echocardiography , Female , Heart Rate/physiology , Humans , Male , Prospective StudiesABSTRACT
In neuroscientific experiments and applications, working with auditory stimuli demands software tools for generation and acquisition of raw audio, for composition and tailoring of that material into finished stimuli, for precisely timed presentation of the stimuli, and for experimental session recording. Numerous programming tools exist to approach these tasks, but their differing specializations and conventions demand extra time and effort for integration. In particular, verifying stimulus timing requires extensive engineering effort when developing new applications. This paper has two purposes. The first is to present audiomath (https://pypi.org/project/audiomath), a sound software library for Python that prioritizes the needs of neuroscientists. It minimizes programming effort by providing a simple object-oriented interface that unifies functionality for audio generation, manipulation, visualization, decoding, encoding, recording, and playback. It also incorporates specialized tools for measuring and optimizing stimulus timing. The second purpose is to relay what we have learned, during development and application of the software, about the twin challenges of delivering stimuli precisely at a certain time, and of precisely measuring the time at which stimuli were delivered. We provide a primer on these problems and the possible approaches to them. We then report audio latency measurements across a range of hardware, operating systems and settings, to illustrate the ways in which hardware and software factors interact to affect stimulus presentation performance, and the resulting pitfalls for the programmer and experimenter. In particular, we highlight the potential conflict between demands for low latency, low variability in latency ("jitter"), cooperativeness, and robustness. We report the ways in which audiomath can help to map this territory and provide a simplified path toward each application's particular priority. By unifying audio-related functionality and providing specialized diagnostic tools, audiomath both simplifies and potentiates the development of neuroscientific applications in Python.
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INTRODUCTION: Diseases and non-battle injuries (DNBIs) are common on UK military deployments, but the collection and analysis of clinically useful data on these remain a challenge. Standard medical returns do not provide adequate clinical information, and clinician-led approaches have been laudable, but not integrated nor standardised nor used long-term. Op TRENTON is a novel UK military humanitarian operation in support of the United Nations Mission in South Sudan, which included the deployment of UK military level 1 and level 2 medical treatment facilities at Bentiu to provide healthcare for UK and United Nations (UN) personnel. METHODS: A service evaluation of patient consultations and admissions at the UK military level 2 hospital was performed using two data sets collected by the emergency department (ED) and medicine (MED) teams. RESULTS: Over a three-month (13-week) period, 286 cases were seen, of which 51% were UK troops, 29% were UN civilians and 20% were UN troops. The ED team saw 175 cases (61%) and provided definitive care for 113 (40%), whereas the MED team saw and provided definitive care for 128 cases (45%). Overall, there were 75% with diseases and 25% with non-battle injuries. The most common diagnoses seen by the ED team were musculoskeletal injuries (17%), unidentified non-malarial undifferentiated febrile illness (UNMUFI) (17%), malaria (13%), chemical pneumonitis (13%) and wounds (8%). The most common diagnoses seen by the MED team were acute gastroenteritis (AGE) (56%), UNMUFI (12%) and malaria (9%). AGE was due to viruses (31%), diarrhoeagenic Escherichia coli (32%), other bacteria (6%) and protozoa (12%). CONCLUSION: Data collection on DNBIs during the initial phase of this deployment was clinically useful and integrated between different departments. However, a standardised, long-term solution that is embedded into deployed healthcare is required. The clinical activity recorded here should be used for planning, training, service development and targeted research.
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Military Personnel , Emergency Service, Hospital , Hospitals, Military , Humans , South Sudan/epidemiology , United Kingdom/epidemiology , United StatesABSTRACT
Undifferentiated febrile illnesses present diagnostic and treatment challenges in the Firm Base, let alone in the deployed austere environment. We report a series of 14 cases from Operation TRENTON in South Sudan in 2017 that coincided with the rainy season, increased insect numbers and a Relief in Place. The majority of patients had headaches, myalgia, arthralgia and back pain, as well as leucopenia and thrombocytopenia. No diagnoses could be made in theatre, despite a sophisticated deployed laboratory being available, and further testing in the UK, including next-generation sequencing, was unable to establish an aetiology. Such illnesses are very likely to present in tropical environments, where increasing numbers of military personnel are being deployed, and clinicians must be aware of the non-specific presentation and treatment, as well as the availability of Military Infection Reachback services to assist in the management of these cases.
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Fever , Military Personnel , Fever/diagnosis , Headache/diagnosis , Humans , South Sudan/epidemiologyABSTRACT
The contrast sensitivity function (CSF) is an informative measure of visual health, but the practical difficulty of measuring it has impeded detailed analyses of its relationship to different visual disorders. Furthermore, most existing tasks cannot be used in populations with cognitive impairment. We analyzed detailed CSFs measured with a nonverbal procedure called "Gradiate," which efficiently infers visibility from eye movements and manipulates stimulus appearance in real time. Sixty observers of varying age (38 with refractive error) were presented with moving stimuli. Stimulus spatial frequency and contrast advanced along 15 radial sweeps through CSF space in response to stimulus-congruent eye movements. A point on the CSF was recorded when tracking ceased. Gradiate CSFs were reliable and in high agreement with independent low-contrast acuity thresholds. Overall CSF variation was largely captured by two orthogonal factors ("radius" and "slope") or two orthogonal shape factors when size was normalized ("aspect ratio" and "curvature"). CSF radius was highly predictive of LogMAR acuity, as were aspect ratio and curvature together, but only radius was predictive of observer age. Our findings suggest that Gradiate holds promise for assessing spatial vision in both verbal and nonverbal populations and indicate that variation between detailed CSFs can reveal useful information about visual health.
Subject(s)
Contrast Sensitivity/physiology , Eye Movements/physiology , Adolescent , Adult , Aged , Child , Female , Humans , Male , Middle Aged , Motion Perception/physiology , Spatial Processing , Visual Acuity/physiology , Young AdultABSTRACT
AIMS: There is currently no gold-standard definition or method for identifying suicide clusters, resulting in considerable heterogeneity in the types of suicide clusters that are detected. This study sought to identify the characteristics, mechanisms and parameters of suicide clusters using three cluster detection methods. Specifically, the study aimed to: (1) determine the overlap in suicide clusters among each method, (2) compare the spatial and temporal parameters associated with different suicide clusters and (3) identify the demographic characteristics and rates of exposure to suicide among cluster and non-cluster members. METHODS: Suicide data were obtained from the National Coronial Information System. N = 3027 Australians, aged 10-24 who died by suicide in 2006-2015 were included. Suicide clusters were determined using: (1) poisson scan statistics, (2) a systematic search of coronial inquests and (3) descriptive network analysis. These methods were chosen to operationalise three different definitions of suicide clusters, namely clusters that are: (1) statistically significant, (2) perceived to be significant and (3) characterised by social links among three or more suicide descendants. For each method, the demographic characteristics and rates of exposure to suicide were identified, in addition to the maximum duration of suicide clusters, the geospatial overlap between suicide clusters, and the overlap of individual cluster members. RESULTS: Eight suicide clusters (69 suicides) were identified from the scan statistic, seven (40 suicides) from coronial inquests; and 11 (37 suicides) from the descriptive network analysis. Of the eight clusters detected using the scan statistic, two overlapped with clusters detected using the descriptive network analysis and one with clusters identified from coronial inquests. Of the seven clusters from coronial inquests, four overlapped with clusters from the descriptive network analysis and one with clusters from the scan statistic. Overall, 9.2% (12 suicides) of individuals were identified by more than one method. Prior exposure to suicide was 10.1% (N = 7) in clusters from the scan statistic, 32.5% (N = 13) in clusters from coronial inquest and 56.8% (N = 21) in clusters from the descriptive network analysis. CONCLUSION: Each method identified markedly different suicide clusters. Evidence of social links between cluster members typically involved clusters detected using the descriptive network analysis. However, these data were limited to the availability information collected as part of the police and coroner investigation. Communities tasked with detecting and responding to suicide clusters may benefit from using the spatial and temporal parameters revealed in descriptive studies to inform analyses of suicide clusters using inferential methods.
Subject(s)
Suicide/statistics & numerical data , Adolescent , Australia , Child , Cluster Analysis , Epidemiologic Studies , Female , Humans , Residence Characteristics , Risk Factors , Suicide/trends , Young AdultABSTRACT
[This corrects the article DOI: 10.1186/s41182-020-00203-0.].
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BACKGROUND: The novel coronavirus (COVID-19) is responsible for more fatalities than the SARS coronavirus, despite being in the initial stage of a global pandemic. The first suspected case in the Philippines was investigated on January 22, 2020, and 633 suspected cases were reported as of March 1. We describe the clinical and epidemiological aspects of the first two confirmed COVID-19 cases in the Philippines, both admitted to the national infectious disease referral hospital in Manila. CASE PRESENTATION: Both patients were previously healthy Chinese nationals on vacation in the Philippines travelling as a couple during January 2020. Patient 1, a 39-year-old female, had symptoms of cough and sore throat and was admitted to San Lazaro Hospital in Manila on January 25. Physical examination was unremarkable. Influenza B, human coronavirus 229E, Staphylococcus aureus and Klebsiella pneumoniae were detected by PCR on initial nasopharyngeal/oropharyngeal (NPS/OPS) swabs. On January 30, SARS-CoV-2 viral RNA was reported to be detected by PCR on the initial swabs and she was identified as the first confirmed COVID-19 case in the Philippines. Her symptoms resolved, and she was discharged. Patient 2, a 44-year-old male, had symptoms of fever, cough, and chills. Influenza B and Streptococcus pneumoniae were detected by PCR on initial NPS/OPS swabs. He was treated for community-acquired pneumonia with intravenous antibiotics, but his condition deteriorated and he required intubation. On January 31, SARS-CoV-2 viral RNA was reported to be detected by PCR on the initial swabs, and he was identified as the 2nd confirmed COVID-19 infection in the Philippines. On February 1, the patient's condition deteriorated, and following a cardiac arrest, it was not possible to revive him. He was thus confirmed as the first COVID-19 death outside of China. CONCLUSIONS: This case report highlights several important clinical and public health issues. Despite both patients being young adults with no significant past medical history, they had very different clinical courses, illustrating how COVID-19 can present with a wide spectrum of disease. As of March 1, there have been three confirmed COVID-19 cases in the Philippines. Continued vigilance is required to identify new cases.