Public Health Resilience Checklist for High-Consequence Infectious Diseases-Informed by the Domestic Ebola Response in the United States.

CONTEXT: The experiences of communities that responded to confirmed cases of Ebola virus disease in the United States provide a rare opportunity for collective learning to improve resilience to future high-consequence infectious disease events. DESIGN: Key informant interviews (n = 73) were conducted between February and November 2016 with individuals who participated in Ebola virus disease planning or response in Atlanta, Georgia; Dallas, Texas; New York, New York; or Omaha, Nebraska; or had direct knowledge of response activities. Participants represented health care; local, state, and federal public health; law; local and state emergency management; academia; local and national media; individuals affected by the response; and local and state governments. Two focus groups were then conducted in New York and Dallas, and study results were vetted with an expert advisory group. RESULTS: Participants focused on a number of important areas to improve public health resilience to high-consequence infectious disease events, including governance and leadership, communication and public trust, quarantine and the law, monitoring programs, environmental decontamination, and waste management. CONCLUSIONS: Findings provided the basis for an evidence-informed checklist outlining specific actions for public health authorities to take to strengthen public health resilience to future high-consequence infectious disease events.

Proof-of-concept recall-by-genotype study of extremely low and high Alzheimer's polygenic risk reveals autobiographical deficits and cingulate cortex correlates.

BACKGROUND: Genome-wide association studies demonstrate that Alzheimer's disease (AD) has a highly polygenic architecture, where thousands of independent genetic variants explain risk with high classification accuracy. This AD polygenic risk score (AD-PRS) has been previously linked to preclinical cognitive and neuroimaging features observed in asymptomatic individuals. However, shared variance between AD-PRS and neurocognitive features are small, suggesting limited preclinical utility. METHODS: Here, we recruited sixteen clinically asymptomatic individuals (mean age 67; range 58-76) with either extremely low / high AD-PRS (defined as at least 2 standard deviations from the wider sample mean (N = 4504; N EFFECTIVE = 90)) with comparable age sex and education level. We assessed group differences in autobiographical memory and T1-weighted structural neuroimaging features. RESULTS: We observed marked reductions in autobiographical recollection (Cohen's d = - 1.66; P FDR = 0.014) and midline structure (cingulate) thickness (Cohen's d = - 1.55, P FDR = 0.05), with no difference in hippocampal volume (P > 0.3). We further confirm the negative association between AD-PRS and cingulate thickness in a larger study with a comparable age (N = 31,966, ß = - 0.002, P = 0.011), supporting the validity of our approach. CONCLUSIONS: These observations conform with multiple streams of prior evidence suggesting alterations in cingulate structures may occur in individuals with higher AD genetic risk. We were able to use a genetically informed research design strategy that significantly improved the efficiency and power of the study. Thus, we further demonstrate that the recall-by-genotype of AD-PRS from wider samples is a promising approach for the detection, assessment, and intervention in specific individuals with increased AD genetic risk.

Reduced brain oxygen metabolism in patients with multiple sclerosis: Evidence from dual-calibrated functional MRI.

Cerebral energy deficiency is increasingly recognised as an important feature of multiple sclerosis (MS). Until now, we have lacked non-invasive imaging methods to quantify energy utilisation and mitochondrial function in the human brain. Here, we used novel dual-calibrated functional magnetic resonance imaging (dc-fMRI) to map grey-matter (GM) deoxy-haemoglobin sensitive cerebral blood volume (CBVdHb), cerebral blood flow (CBF), oxygen extraction fraction (OEF), and cerebral metabolic rate of oxygen consumption (CMRO2) in patients with MS (PwMS) and age/sex matched controls. By integrating a flow-diffusion model of oxygen transport, we evaluated the effective oxygen diffusivity of the capillary network (DC) and the partial pressure of oxygen at the mitochondria (PmO2). Significant between-group differences were observed as decreased CBF (p = 0.010), CMRO2 (p < 0.001) and DC (p = 0.002), and increased PmO2 (p = 0.043) in patients compared to controls. No significant differences were observed for CBVdHb (p = 0.389), OEF (p = 0.358), or GM volume (p = 0.302). Regional analysis showed widespread reductions in CMRO2 and DC for PwMS. Our findings may be indicative of reduced oxygen demand or utilisation in the MS brain and mitochondrial dysfunction. Our results suggest changes in brain physiology may precede MRI-detectable GM loss and may contribute to disease progression and neurodegeneration.

Parent/Caregiver Views of the Effectiveness of Speech-Language Pathology for Children Born With Cleft Palate Delivered via Telemedicine During COVID-19.

PURPOSE: The purpose of this study was to describe and examine parent views of speech-language pathology (SLP) for children born with cleft palate delivered via telemedicine during the COVID-19 pandemic in the United Kingdom (UK). METHOD: Parents were asked whether they found this method of delivery "very effective," "somewhat effective," or "not at all effective." Free text was then invited. There were 212 responses. Ordinal chi-square, Kruskal-Wallis, or Fisher's exact tests examined associations between parent views of effectiveness and biological variables and socioeconomic status. Free text responses were analyzed using qualitative content analysis. RESULTS: One hundred and forty (66.0%) respondents reported that SLP delivered via telemedicine was "somewhat effective," 56 (26.4%) "very effective," and 16 (7.6%) "not at all effective." There was no evidence of an association between parent reported effectiveness and any of the explanatory variables. Parent-reported challenges impacting on effectiveness included technology issues and keeping their children engaged with sessions. Importantly, telemedicine was viewed as "better than nothing." CONCLUSIONS: Most parents reported that they felt SLP delivered via telemedicine during the first few months of the COVID-19 pandemic in the UK was at least "somewhat effective." It is important to interpret this in the context of there being no other method of service delivery during this time and that this study only represents families who were able to access SLP delivered via telemedicine. Further work is needed to identify which children with cleft palate might benefit from SLP delivered via telemedicine to inform postpandemic service provision.

Alzheimer's genetic risk effects on cerebral blood flow across the lifespan are proximal to gene expression.

Cerebrovascular dysregulation such as altered cerebral blood flow (CBF) can be observed in Alzheimer's disease (AD) and may precede symptom onset. Genome wide association studies show that AD has a polygenic aetiology, providing a tool for studying AD susceptibility across the lifespan. Here, we ascertain whether the AD genetic risk effects on CBF previously observed (Chandler et al., 2019) are also present in later life. Consistent with our prior observations, AD genetic risk score (AD-GRS) was associated with reduced CBF in the ADNI sample. The regional association between AD-GRS and CBF were also spatially similar. Furthermore, CBF was related to the regional mRNA transcript expression of AD risk genes proximal to AD-GRS risk loci. These observations suggest that AD risk alleles may reduce neurovascular process such as CBF, potentially via mechanisms such as regional expression of proximal AD risk genes as an antecedent AD pathophysiology. Our observations help establish processes that underpin AD genetic risk-related reductions in CBF as a therapeutic target prior to the onset of neurodegeneration.

A flow-diffusion model of oxygen transport for quantitative mapping of cerebral metabolic rate of oxygen (CMRO2) with single gas calibrated fMRI.

One promising approach for mapping CMRO2 is dual-calibrated functional MRI (dc-fMRI). This method exploits the Fick Principle to combine estimates of CBF from ASL, and OEF derived from BOLD-ASL measurements during arterial O2 and CO2 modulations. Multiple gas modulations are required to decouple OEF and deoxyhemoglobin-sensitive blood volume. We propose an alternative single gas calibrated fMRI framework, integrating a model of oxygen transport, that links blood volume and CBF to OEF and creates a mapping between the maximum BOLD signal, CBF and OEF (and CMRO2). Simulations demonstrated the method's viability within physiological ranges of mitochondrial oxygen pressure, PmO2, and mean capillary transit time. A dc-fMRI experiment, performed on 20 healthy subjects using O2 and CO2 challenges, was used to validate the approach. The validation conveyed expected estimates of model parameters (e.g., low PmO2), with spatially uniform OEF maps (grey matter, GM, OEF spatial standard deviation ≈ 0.13). GM OEF estimates obtained with hypercapnia calibrated fMRI correlated with dc-fMRI (r = 0.65, p = 2·10-3). For 12 subjects, OEF measured with dc-fMRI and the single gas calibration method were correlated with whole-brain OEF derived from phase measures in the superior sagittal sinus (r = 0.58, p = 0.048; r = 0.64, p = 0.025 respectively). Simplified calibrated fMRI using hypercapnia holds promise for clinical application.

Multimodal hippocampal and amygdala subfield volumetry in polygenic risk for Alzheimer's disease.

Preclinical models of Alzheimer's disease (AD) suggest that volumetric reductions in medial temporal lobe (MTL) structures manifest before clinical onset. AD polygenic risk scores (PRSs) are further linked to reduced MTL volumes (the hippocampus/amygdala); however, the relationship between the PRS and specific subregions remains unclear. We determine the relationship between the AD-PRSs and MTL subregions in a large sample of young participants (N = 730, aged 22-35 years) using a multimodal (T1w/T2w) approach. We first demonstrate that the PRSs for the hippocampus/amygdala predict their respective volumes and specific hippocampal subregions (pFDR < 0.05). We further observe negative relationships between the AD-PRSs and whole hippocampal/amygdala volumes. Critically, we demonstrate novel associations between the AD-PRSs and specific hippocampal subfields such as CA1 (ß = -0.096, pFDR = 0.045) and the fissure (ß = -0.101, pFDR = 0.041). We provide evidence that the AD-PRS is linked to specific MTL subfields decades before AD onset. This may help inform preclinical models of AD risk, providing additional specificity for intervention and further insight into mechanisms by which common AD variants confer susceptibility.

Corrigendum: A Frequency-Domain Machine Learning Method for Dual-Calibrated fMRI Mapping of Oxygen Extraction Fraction (OEF) and Cerebral Metabolic Rate of Oxygen Consumption (CMRO2).

[This corrects the article DOI: 10.3389/frai.2020.00012.].

Tiagabine induced modulation of oscillatory connectivity and activity match PET-derived, canonical GABA-A receptor distributions.

As the most abundant inhibitory neurotransmitter in the mammalian brain, γ-aminobutyric acid (GABA) plays a crucial role in shaping the frequency and amplitude of oscillations, which suggests a role for GABA in shaping the topography of functional connectivity and activity. This study explored the effects of pharmacologically blocking the reuptake of GABA (increasing local concentrations) using the GABA transporter 1 (GAT1) blocker, tiagabine (15 mg). In a placebo-controlled crossover design, we collected resting magnetoencephalography (MEG) recordings from 15 healthy individuals prior to, and at 1-, 3- and 5- hours post, administration of tiagabine and placebo. We quantified whole brain activity and functional connectivity in discrete frequency bands. Drug-by-session (2 × 4) analysis of variance in connectivity revealed interaction and main effects. Post-hoc permutation testing of each post-drug recording vs. respective pre-drug baseline revealed consistent reductions of a bilateral occipital network spanning theta, alpha and beta frequencies, across 1- 3- and 5- hour recordings following tiagabine only. The same analysis applied to activity revealed significant increases across frontal regions, coupled with reductions in posterior regions, across delta, theta, alpha and beta frequencies. Crucially, the spatial distribution of tiagabine-induced changes overlap with group-averaged maps of the distribution of GABAA receptors, from flumazenil (FMZ-VT) PET, demonstrating a link between GABA availability, GABAA receptor distribution, and low-frequency network oscillations. Our results indicate that the relationship between PET receptor distributions and MEG effects warrants further exploration, since elucidating the nature of this relationship may uncover electrophysiologically-derived maps of oscillatory activity as sensitive, time-resolved, and targeted receptor-mapping tools for pharmacological imaging.

A frequency-domain machine learning method for dual-calibrated fMRI mapping of oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen consumption (CMRO2).

Magnetic resonance imaging (MRI) offers the possibility to non-invasively map the brain's metabolic oxygen consumption (CMRO2), which is essential for understanding and monitoring neural function in both health and disease. However, in depth study of oxygen metabolism with MRI has so far been hindered by the lack of robust methods. One MRI method of mapping CMRO2 is based on the simultaneous acquisition of cerebral blood flow (CBF) and blood oxygen level dependent (BOLD) weighted images during respiratory modulation of both oxygen and carbon dioxide. Although this dual-calibrated methodology has shown promise in the research setting, current analysis methods are unstable in the presence of noise and/or are computationally demanding. In this paper, we present a machine learning implementation for the multi-parametric assessment of dual-calibrated fMRI data. The proposed method aims to address the issues of stability, accuracy, and computational overhead, removing significant barriers to the investigation of oxygen metabolism with MRI. The method utilizes a time-frequency transformation of the acquired perfusion and BOLD-weighted data, from which appropriate feature vectors are selected for training of machine learning regressors. The implemented machine learning methods are chosen for their robustness to noise and their ability to map complex non-linear relationships (such as those that exist between BOLD signal weighting and blood oxygenation). An extremely randomized trees (ET) regressor is used to estimate resting blood flow and a multi-layer perceptron (MLP) is used to estimate CMRO2 and the oxygen extraction fraction (OEF). Synthetic data with additive noise are used to train the regressors, with data simulated to cover a wide range of physiologically plausible parameters. The performance of the implemented analysis method is compared to published methods both in simulation and with in-vivo data (n=30). The proposed method is demonstrated to significantly reduce computation time, error, and proportional bias in both CMRO2 and OEF estimates. The introduction of the proposed analysis pipeline has the potential to not only increase the detectability of metabolic difference between groups of subjects, but may also allow for single subject examinations within a clinical context.

Polygenic risk for Alzheimer's disease shapes hippocampal scene-selectivity.

Preclinical models of Alzheimer's disease (AD) suggest APOE modulates brain function in structures vulnerable to AD pathophysiology. However, genome-wide association studies now demonstrate that AD risk is shaped by a broader polygenic architecture, estimated via polygenic risk scoring (AD-PRS). Despite this breakthrough, the effect of AD-PRS on brain function in young individuals remains unknown. In a large sample (N = 608) of young, asymptomatic individuals, we measure the impact of both (i) APOE and (ii) AD-PRS on a vulnerable cortico-limbic scene-processing network heavily implicated in AD pathophysiology. Integrity of this network, which includes the hippocampus (HC), is fundamental for maintaining cognitive function during ageing. We show that AD-PRS, not APOE, selectively influences activity within the HC in response to scenes, while other perceptual nodes remained intact. This work highlights the impact of polygenic contributions to brain function beyond APOE, which could aid potential therapeutic/interventional strategies in the detection and prevention of AD.

Polygenic impact of common genetic risk loci for Alzheimer's disease on cerebral blood flow in young individuals.

Genome-wide association studies (GWAS) show that many common alleles confer risk for developing Alzheimer's disease (AD). These risk loci may contribute to MRI alterations in young individuals, preceding the clinical manifestations of AD. Prior evidence identifies vascular dysregulation as the earliest marker of disease progression. However, it remains unclear whether cerebrovascular function (measured via grey-matter cerebral blood flow (gmCBF)) is altered in young individuals with increased AD genetic risk. We establish relationships between gmCBF with APOE and AD polygenic risk score in a young cohort (N = 75; aged: 19-32). Genetic risk was assessed via a) possessing at least one copy of the APOE ɛ4 allele and b) a polygenic risk score (AD-PRS) estimated from AD-GWAS. We observed a reduction in gmCBF in APOE ɛ4 carriers and a negative relationship between AD-PRS and gmCBF. We further found regional reductions in gmCBF in individuals with higher AD-PRS across the frontal cortex (PFWE < 0.05). Our findings suggest that a larger burden of AD common genetic risk alleles is associated with attenuated cerebrovascular function, during young adulthood. These results suggest that cerebral vasculature is a mechanism by which AD risk alleles confer susceptibility.

"What's happening in Syria even affects the rocks": a qualitative study of the Syrian refugee experience accessing noncommunicable disease services in Jordan.

BACKGROUND: Humanitarian actors and host-countries in the Middle East and North Africa region are challenged with meeting the health needs of Syrian refugees and adjusting the response to contemporary humanitarian conditions - urban-based refugees, stressed host-country health systems and high NCD prevalence. Although several studies have explored NCD prevalence, utilization of services and barriers to access, these analyses took place prior to dramatic shifts in Jordanian health policy and did not account for nuances in health seeking and utilization behaviors or operational barriers. Accordingly, we aimed to understand the depth and nuances of Syrian refugees' experiences accessing NCD services in urban and semi-urban settings in Jordan. METHODS: A qualitative study was conducted to explore the healthcare experiences of Syrian refugees in Jordan. The study team conducted 68 in-depth interviews with Syrian refugees in urban and semi-urban locations in central and northern Jordan. RESULTS: The findings indicated four themes key to understanding the healthcare experience: (1) emotional distress is a central concern and is frequently highlighted as the trigger for a non-communicable disease or its exacerbation; (2) service provision across all sectors - government, NGO, private - is complex, inadequate, expensive and fragmented, making engagement with the health sector physically and financially burdensome; (3) given financial constraints, participants make harmful decisions that further damage their health in order to reduce financial burdens, and (4) host-community members actively exhibit solidarity with their refugee neighbors and specifically do so during emergency health episodes. The findings from this study can be used to inform program design for forcibly displaced persons with NCDs and identify points of entry for effective interventions. CONCLUSIONS: Opportunities exist for humanitarian and host-country actors to provide more comprehensive NCD services and to improve the relevance and the quality of care provided to Syrian refugees in Jordan. Global and national funding will need to align with front-line realities and foster better coordination of services between host-country health systems, private actors and non-governmental organizations.

Recommendations on How to Manage Anticipated Communication Dilemmas Involving Medical Countermeasures in an Emergency.

National investments to facilitate prompt access to safe and effective medical countermeasures (MCMs) (ie, products used to diagnose, prevent, protect from, or treat conditions associated with chemical, biological, radiological, or nuclear threats, or emerging infectious diseases) have little merit if people are not willing to take a recommended MCM during an emergency or inadvertently misuse or miss out on a recommended MCM during an emergency. Informed by the Expert Working Group on MCM Emergency Communication, the Johns Hopkins Center for Health Security developed recommendations for achieving desired public health outcomes through improved MCM communication based on a review of model practices in risk communication, crisis communication, and public warnings; detailed analysis of recent health crises involving MCMs; and development of a scenario depicting future MCM communication dilemmas. The public's topics of concern, emotional requirements, capacity for processing information, and health needs will evolve as an emergency unfolds, from a pre-event period of routine conditions, to a crisis state, to a post-event period of reflection. Thus, MCM communication by public health authorities requires a phased approach that spans from building up a reputation as a trusted steward of MCMs between crises to developing recovery-focused messages about applying newly acquired data about MCM safety, efficacy, and accessibility to improve future situations.

Lessons from the domestic Ebola response: Improving health care system resilience to high consequence infectious diseases.

BACKGROUND: The domestic response to the West Africa Ebola virus disease (EVD) epidemic from 2014-2016 provides a unique opportunity to distill lessons learned about health sector planning and operations from those individuals directly involved. This research project aimed to identify and integrate these lessons into an actionable checklist that can improve health sector resilience to future high-consequence infectious disease (HCID) events. METHODS: Interviews (N = 73) were completed with individuals involved in the domestic EVD response in 4 cities (Atlanta, Dallas, New York, and Omaha), and included individuals who worked in academia, emergency management, government, health care, law, media, and public health during the response. Interviews were transcribed and analyzed qualitatively. Two focus groups were then conducted to expand on themes identified in the interviews. Using these themes, an evidence-informed checklist was developed and vetted for completeness and feasibility by an expert advisory group. RESULTS: Salient themes identified included health care facility issues-specifically identifying assessment and treatment hospitals, isolation and treatment unit layout, waste management, community relations, patient identification, patient isolation, limitations on treatment, laboratories, and research considerations-and health care workforce issues-specifically psychosocial impact, unit staffing, staff training, and proper personal protective equipment. CONCLUSIONS: The experiences of those involved in the domestic Ebola response provide critical lessons that can help strengthen resilience of health care systems and improve future responses to HCID events.

Being prepared: emergency treatment following a nerve agent release.

Nerve agents are extremely toxic and are some of the most lethal substances on earth. This group of chemicals consists of sarin, cyclosarin, soman, tabun, VX, and VR. It is currently unknown how many countries possess these chemicals and in what quantities. These agents work through altering the transmission and breakdown of acetylcholine by binding to, and inactivating, acetylcholinesterase. This results in an uncontrolled and overwhelming stimulation of both muscarinic and nicotinic receptors. Receptor activation at these sites can lead to a wide variety of clinical symptoms, with death frequently resulting from pulmonary edema. Antidotal therapy in this setting largely consists of atropine, pralidoxime, and benzodiazepines, all of which must be administered emergently to limit the progression of symptoms and prevent the enzyme inactivation from becoming permanent. This article reviews the mechanism of action of the nerve agents and their effects on the human body, the currently available therapies to mitigate their impact, and important therapeutic considerations for health care practitioners in the emergency department.