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Anthropogenic contamination has been detected in glacial and proglacial environments around the globe. Through mechanisms of secondary release, these contaminants are finding their way into glacial hydrological systems and downstream environments, with potential to impact hundreds of millions of people who rely on glacial meltwater for water, food and energy security worldwide. The first part of our progress report outlined the sources and accumulation mechanisms of contaminants in glacial environments (Part I: Inputs and accumulation). Here we assess processes of contaminant release, pathways to downstream environments, and socio-environmental consequences. We reflect on the potential impacts these contaminants could have for human, ecosystem, and environmental health, as well as framing glacial contaminants within the context of the water-food-energy nexus. Improved understanding of these processes and impacts, while crucially embedding local knowledge, will help to develop key policy and mitigation strategies to address future risk of contaminant release from glaciers.

Historically, glaciers have been seen as pristine environments. However, recent research has shown that glaciers can accumulate and store contaminants over long timescales, through processes such as atmospheric deposition, sedimentation, glacial hydrology and mass movements. Studies have identified numerous anthropogenically derived contaminants within the global cryosphere, including the six we focus on here: fallout radionuclides; microplastics; persistent organic pollutants; potentially toxic elements; black carbon and nitrate-based contaminants. These contaminants are relatively well-studied in other environments; however, their dynamics and role in glaciated systems is still poorly understood. Therefore, it is important to assess and quantify contaminant levels within the cryosphere, so that current and future threats can be fully understood and mitigated. In this first progress report ( Part I: Inputs and accumulation), we review the current state of knowledge of six of the most common anthropogenic contaminants found in the cryosphere, and consider their sources, transportation, accumulation and concentration within glacial systems. A second progress report ( Part II: Release and downstream consequences) will outline how these contaminants leave glacial systems and the consequences that this release can have for communities and ecosystems reliant on glacial meltwater.

Background West Nile virus (WNV) is the leading cause of mosquito-borne illness in the continental USA. WNV occurrence has high spatiotemporal variation, and current approaches to targeted control of the virus are limited, making forecasting a public health priority. However, little research has been done to compare strengths and weaknesses of WNV disease forecasting approaches on the national scale. We used forecasts submitted to the 2020 WNV Forecasting Challenge, an open challenge organized by the Centers for Disease Control and Prevention, to assess the status of WNV neuroinvasive disease (WNND) prediction and identify avenues for improvement. Methods We performed a multi-model comparative assessment of probabilistic forecasts submitted by 15 teams for annual WNND cases in US counties for 2020 and assessed forecast accuracy, calibration, and discriminatory power. In the evaluation, we included forecasts produced by comparison models of varying complexity as benchmarks of forecast performance. We also used regression analysis to identify modeling approaches and contextual factors that were associated with forecast skill. Results Simple models based on historical WNND cases generally scored better than more complex models and combined higher discriminatory power with better calibration of uncertainty. Forecast skill improved across updated forecast submissions submitted during the 2020 season. Among models using additional data, inclusion of climate or human demographic data was associated with higher skill, while inclusion of mosquito or land use data was associated with lower skill. We also identified population size, extreme minimum winter temperature, and interannual variation in WNND cases as county-level characteristics associated with variation in forecast skill. Conclusions Historical WNND cases were strong predictors of future cases with minimal increase in skill achieved by models that included other factors. Although opportunities might exist to specifically improve predictions for areas with large populations and low or high winter temperatures, areas with high case-count variability are intrinsically more difficult to predict. Also, the prediction of outbreaks, which are outliers relative to typical case numbers, remains difficult. Further improvements to prediction could be obtained with improved calibration of forecast uncertainty and access to real-time data streams (e.g. current weather and preliminary human cases). Graphical Abstract

It has been shown that the presence of a hand holding a wireless handset (cell phone) can influence antenna efficiency and the measurement of specific absorption rate (SAR) and electromagnetic compatibility. Head phantoms, used in handset compliance testing to estimate SAR in the head, have achieved low cost and multi-frequency use. Head phantoms typically consist of a thin plastic shell, open on the top, holding a tissue simulating fluid. The specific simulant fluid used is determined by the radio frequency of the test. IEC 62209–1 has recipes, using safe nontoxic materials, for all the required frequency bands. Thus, head phantoms can be reused at different frequencies simply by changing the tissue simulating fluid. However, standards have not adopted the use of hand phantoms because SAR limits in limbs are less restrictive than the head, the tissue depth in a hand is insufficient to make accurate measurements with current electric field probes, and the cost of a solid hand phantom is limited to a single frequency band. Our goal was to determine whether 3D printing techniques would allow the construction of a hand phantom with the same utility as existing head phantoms. We developed this phantom based on computer simulations to determine how much human anatomy needed to be included in the phantom to obtain results consistent with actual use. Electric field scans of a handset alone, and held by the hand phantom, were performed. Comparison of handset scans using the phantom and human subjects was planned, but not performed due to Covid-19 restrictions and subsequent changes in priorities. We feel a fluid-filled 3D printed hand phantom is viable and practical. The 3D print files are available on GitHub.

The disaccharide galactose-α-1,3-galactose (alpha-gal) is expressed in mammals other than humans, apes, and old-world monkeys. In humans, elevated immunoglobulin-E (IgE) antibodies specific for alpha-gal can result in allergic hypersensitivity known as alpha-gal syndrome (AGS). Case reports and series suggest that tick bites can induce alpha-gal specific IgE antibodies.Evaluate tick exposure as a risk factor for AGS and elevated alpha-gal specific IgE (sIgE).We conducted a case-control study comparing AGS patients from a North Carolina allergy clinic with controls who were patients at a nearby internal medicine clinic. Cases and controls were administered a questionnaire to obtain information about demographics, home environment, outdoor activities, and recollection of tick bite. Serum samples taken at the time of enrollment were tested for total IgE, alpha-gal sIgE, and antibodies to other tickborne pathogens.AGS patients were more likely to recall finding a tick on themselves (OR=11.20, 95% CI 4.97-25.15), live near wooded forest (OR=2.27, 95% CI 0.92-5.55), and spend 17 or more hours per week outdoors in wooded areas (OR=5.58, 95% CI 2.56-12.19). AGS patients were also more likely to report 4 or more tick bites (OR=33.05, 95% CI 9.92-155.12) and reactions at the site of tick bites (OR=7.93, 95% CI 3.74-16.80). Elevated alpha-gal sIgE was also observed in 33% of controls and was also associated with tick exposure in the controls (OR=4.25, 95% CI 2.21-8.18).The results define tick bite as a risk factor for AGS and elevated alpha-gal sIgE.

Alpha-gal syndrome (AGS) is an IgE-mediated allergy to galactose-alpha-1,3-galactose. Clinical presentation ranges from hives to anaphylaxis; episodes typically occur 2-6 h after exposure to alpha-gal-containing products. In the United States, lone star tick bites are associated with the development of AGS. To characterize features of AGS, we evaluated a cohort of patients presenting for care at the University of North Carolina, focusing on symptoms, severity, and identifying features unique to specific alpha-gal-containing product exposures.We performed a chart review and descriptive analysis of 100 randomly selected patients with AGS during 2010-2019.Median age at onset was 53 years, 56% were female, 95% reported White race, 86% reported a history of tick bite, and 75% met the criteria for anaphylaxis based on the involvement of ≥2 organ systems. Those reporting dairy reactions were significantly less likely to report isolated mucocutaneous symptoms (3% vs. 24%; ratio [95% CI]: 0.1 [0.1, 0.3]) than those who tolerated dairy, and were more likely to report gastrointestinal symptoms (79% vs. 59%; ratio [95% CI]: 1.3 [0.7, 2.6]), although this difference was not statistically significant. Dairy-tolerant patients demonstrated higher alpha-gal sIgE titers (as a percentage of total IgE) than dairy-reactive patients (GM 4.1 [95% CI: 2.7, 6.1] vs. GM 2.5 [95% CI: 1.3, 4.8], respectively; ratio -1.6 [95% CI: -1.0, 3.9]).While tick exposure is common in the southern United States, nearly all AGS patients reported a tick bite. Gastrointestinal symptoms were prominent among those reporting reactions to dairy. Anaphylaxis was common, underscoring the severity and need to raise awareness of AGS among patients and providers.

Background Implantable pacemakers and implantable cardioverter-defibrillators (ICDs) are designed to include a "magnet mode" feature that can be activated from magnets stronger than 10 G. This feature is designed to be used when a patient is undergoing a procedure where electromagnetic interference is possible, or anytime suspension of tachycardia detection and therapy is needed. A publication in Heart Rhythm demonstrates an iPhone 12 triggering the magnet mode of a Medtronic ICD. Objective The purpose of this study is to determine the separation distance between consumer electronic devices that may create magnetic interference, including cell phones and smart watches, and implantable pacemakers and ICDs where magnet mode can be triggered. Methods The static magnetic fields of the iPhone 12 models and Apple Watch were measured at several planes in 1 cm resolution using an FW Bell 5180 Gauss Meter with STD18-0404 Transverse probe (unidirectional probe). Results All iPhone 12 and Apple Watch 6 models tested have static magnetic fields significantly greater than 10 G in close proximity (1–11 mm), which attenuates to below 10 G between 11 and 20 mm. Conclusion The findings of this study support the US Food and Drug Administration recommendation that patients keep any consumer electronic devices that may create magnetic interference, including cell phones and smart watches, at least 6 inches away from implanted medical devices, in particular pacemakers and cardiac defibrillators.

An amendment to this paper has been published and can be accessed via the original article.

BackgroundTriatomine bugs, the vectors of Chagas disease, associate with vertebrate hosts in highly diverse ecotopes. When these blood-sucking bugs adapt to new microhabitats, their phenotypes may change. Although understanding phenotypic variation is key to the study of adaptive evolution and central to phenotype-based taxonomy, the drivers of phenotypic change and diversity in triatomines remain poorly understood.Methods/FindingsWe combined a detailed phenotypic appraisal (including morphology and morphometrics) with mitochondrialcytband nuclear ITS2 DNA-sequence analyses to studyRhodnius ecuadoriensispopulations from across the species’ range. We found three major, naked-eye phenotypic variants. Southern-Andean bugs (SW Ecuador/NW Peru) from house and vertebrate-nest microhabitats are typical, light-colored, small bugs with short heads/wings. Northern-Andean bugs (W Ecuador wet-forest palms) are dark, large bugs with long heads/wings. Finally, northern-lowland bugs (coastal Ecuador dry-forest palms) are light-colored and medium-sized. Wing and (size-free) head shapes are similar across Ecuadorian populations, regardless of habitat or naked-eye phenotype, but distinct in Peruvian bugs. Bayesian phylogenetic and multispecies-coalescent DNA-sequence analyses strongly suggest that Ecuadorian and Peruvian populations are two independently-evolving lineages, with little within-lineage structuring/differentiation.ConclusionsWe report sharp naked-eye phenotypic divergence of genetically similar EcuadorianR. ecuadoriensis(house/nest southern-Andeanvs. palm-dwelling northern bugs; and palm-dwelling Andeanvs. lowland); and sharp naked-eye phenotypic similarity of typical, yet genetically distinct, southern-Andean bugs from house and nest (but not palm) microhabitats (SW Ecuadorvs. NW Peru). This remarkable phenotypic diversity within a single nominal species likely stems from microhabitat adaptations possibly involving predator-driven selective pressure (yielding substrate-matching camouflage coloration) and a shift from palm-crown to vertebrate-nest microhabitats (yielding smaller bodies and shorter heads and wings). These findings shed new light on the origins of phenotypic diversity in triatomines, warn against excess reliance on phenotype-based triatomine-bug taxonomy, and confirm the Triatominae as an informative model-system for the study of phenotypic change under ecological pressure.Author summaryTriatomine bugs feed on the blood of vertebrates including humans and transmit the parasite that causes Chagas disease. The bugs, of which 150+ species are known, are highly diverse in size, shape, and color. Some species look so similar that they are commonly confused, whereas a few same-species populations look so different that they were thought to be separate species. Despite the crucial role of naked-eye phenotypes in triatomine-bug identification and classification (which are essential for vector control-surveillance), the origins of this variation remain unclear. Here, we describe a striking case of phenotypic divergence, with genetically similar bugs looking very different from one another, and phenotypic convergence, with bugs from two genetically distinct populations (likely on their way to speciation) looking very similar – and all within a single nominal species,Rhodnius ecuadoriensis. Phenotypically divergent populations occupy different ecological regions (wetvs. dry) and microhabitats (palm-crownsvs. vertebrate nests), whereas convergent populations occupy man-made and nest (but not palm) microhabitats. These findings suggest that triatomines can ‘respond’ to ecological novelty by changing their external, naked-eye phenotypes as they adapt to new microhabitats. We therefore warn that phenotypic traits such as overall size or color may confound triatomine-bug species identification and classification.

Reported cases of vector-borne diseases in the United States have more than tripled since 2004, characterized by steadily increasing incidence of tick-borne diseases and sporadic outbreaks of domestic and invasive mosquito-borne diseases. An effective public health response to these trends relies on public health surveillance and laboratory systems, proven prevention and mitigation measures, scalable capacity to implement these measures, sensitive and specific diagnostics, and effective therapeutics. However, significant obstacles hinder successful implementation of these public health strategies. The recent emergence of Haemaphysalis longicornis, the first invasive tick to emerge in the United States in approximately 80 years, serves as the most recent example of the need for a coordinated public health response. Addressing the dual needs for innovation and discovery and for building state and local capacities may overcome current challenges in vector-borne disease prevention and control, but will require coordination across a national network of collaborators operating under a national strategy. Such an effort should reduce the impact of emerging vectors and could reverse the increasing trend of vector-borne disease incidence and associated morbidity and mortality.

Plague, a fleaborne rodent-associated zoonosis, is a neglected disease with most recent cases reported from east and central Africa and Madagascar. Because of its low incidence and sporadic occurrence, most of our knowledge of plague ecology, prevention, and control derives from investigations conducted in response to human cases. Long-term studies (which are uncommon) are required to generate data to support plague surveillance, prevention, and control recommendations. Here we describe a 15-year, multidisciplinary commitment to plague in the West Nile region of Uganda that led to significant advances in our understanding of where and when persons are at risk for plague infection and how to reduce morbidity and mortality. These findings provide data-driven support for several existing recommendations on plague surveillance and prevention and may be generalizable to other plague foci.

Introduction Vectorborne diseases are major causes of death and illness worldwide. In the United States, the most common vectorborne pathogens are transmitted by ticks or mosquitoes, including those causing Lyme disease; Rocky Mountain spotted fever; and West Nile, dengue, and Zika virus diseases. This report examines trends in occurrence of nationally reportable vectorborne diseases during 2004-2016. Methods Data reported to the National Notifiable Diseases Surveillance System for 16 notifiable vectorborne diseases during 2004-2016 were analyzed; findings were tabulated by disease, vector type, location, and year. Results A total 642,602 cases were reported. The number of annual reports of tickborne bacterial and protozoan diseases more than doubled during this period, from >22,000 in 2004 to >48,000 in 2016. Lyme disease accounted for 82% of all tickborne disease reports during 2004-2016. The occurrence of mosquitoborne diseases was marked by virus epidemics. Transmission in Puerto Rico, the U.S. Virgin Islands, and American Samoa accounted for most reports of dengue, chikungunya, and Zika virus diseases; West Nile virus was endemic, and periodically epidemic, in the continental United States. Conclusions and implications for public health practice Vectorborne diseases are a large and growing public health problem in the United States, characterized by geographic specificity and frequent pathogen emergence and introduction. Differences in distribution and transmission dynamics of tickborne and mosquitoborne diseases are often rooted in biologic differences of the vectors. To effectively reduce transmission and respond to outbreaks will require major national improvement of surveillance, diagnostics, reporting, and vector control, as well as new tools, including vaccines.

Background Alpha-gal syndrome (AGS) is an emerging immunoglobulin E (IgE)–mediated allergy to galactose-alpha-1,3-galactose (alpha-gal). The geographic distribution and burden of AGS in the United States are unknown. Objective To characterize alpha-gal IgE testing patterns and describe the trends and distribution from 2010 to 2018 in the United States. Methods This retrospective analysis included all persons tested for alpha-gal IgE antibodies by Viracor-IBT Laboratories (Lee’s Summit, Missouri), the primary site of testing in the United States. Data included age and sex of person tested, specimen state of origin, collection date, and result value; persons with at least 1 positive test result (≥0.1 kU/L) were compared with negatives. Proportions tested and with positive test results were calculated using the US Census population estimates. Results Overall, 122,068 specimens from 105,674 persons were tested for alpha-gal IgE during July 1, 2010, to December 31, 2018. Nearly one-third (34,256, 32.4%) had at least 1 positive result. The number of persons receiving positive test results increased 6-fold from 1110 in 2011 to 7798 in 2018. Of those receiving positive test results, mean [SD] age was 46.9 (19.8) years; men were more likely to test positive than women (43.3% vs 26.0%). Arkansas, Virginia, Kentucky, Oklahoma, and Missouri had the highest number of persons who were tested and had a positive result per 100,000 population. Conclusion More than 34,000 persons, most presumably symptomatic, have received positive test results for IgE antibodies to alpha-gal, suggesting AGS is an increasingly recognized public health problem. The geographic distribution of persons who tested positive is consistent with exposure to Amblyomma americanum ticks.

Introduction Research suggests modifiable lifestyle behaviors are associated with delayed cognitive decline. Identifying modifiable lifestyle behaviors in African Americans is critical because they are more likely to be diagnosed with Alzheimer’s disease and other related dementias. Evidence shows the positive effects of physical activity (PA) on cognitive functioning. Sleep quality also impacts cognitive functioning. Therefore, the purpose of this study examined how sleep quality and sex moderated the relationship between PA and cognitive functioning in African Americans. Methods A sample of 147 African Americans (mean age 59) completed the Pittsburgh Sleep Quality Inventory (PSQI) and a battery of cognitive tests (The Delis-Kaplan Executive Function System (DKEFS) Verbal Fluency Test, The Stroop Color Word Test and Trail Making Test). Participants completed a participant screener to determine PA frequency and intensity. Anthropomorphic measures were also obtained. A moderated moderation analysis was conducted. Results Poor sleep quality was associated with poorer performance on a verbal fluency task after controlling for age, BMI and years of education (B=-1.37, p=.012). There was a significant interaction between PA frequency and sleep quality on verbal fluency performance (B=0.42, p=.047). Additionally, there was a significant interaction between sleep quality and sex on verbal fluency performance (B=0.80, p=.016). Further adjustments revealed significant conditional effects such that more frequent PA per week improved verbal fluency performance among women, who reported better sleep quality (B=0.20, p=0.03). Conclusion The current study suggests sleep quality strengthens the relationship between PA and cognitive performance, specifically in African-American women. Consistent with previous studies, our findings support the need to target sleep quality and PA in women as modifiable lifestyle factors that may delay cognitive decline. Support This research was funded by the Office of the Provost at Howard University.

Vector-borne diseases (VBDs) cause significant morbidity and mortality each year in the United States. Over the last 14 yr, over 700,000 cases of diseases carried by ticks, mosquitoes, and fleas have been reported from U.S. states and territories to the Centers for Disease Control and Prevention. The number of reported cases has been increasing annually with two major trends: a steady increase in tick-borne diseases and increasing intermittent outbreaks of mosquito-borne arboviruses. The factors that are driving VBD introduction and emergence vary among diseases but are not likely to disappear, indicating that current trends will continue and probably worsen in the absence of effective prevention and control tools and implementation capacity. There are a number of challenges to preventing VBDs, including the lack of vaccines and effective vector control tools, insecticide resistance, and eroding technical capacities in public health entomology at federal, state, and local levels. For these reasons, a national strategy is needed to address VBD threats and to reverse the alarming trend in morbidity and mortality associated with these diseases.

Background Vector-borne diseases are an important cause of morbidity and mortality in the USA. Effective, convenient prevention methods are needed. Long-lasting permethrin-impregnated (LLPI) clothing can prevent tick bites, however, additional information is needed on the real-world effectiveness and safety of this preventative measure. Methods In this pilot study, we recruited state and county park employees from North Carolina to wear LLPI uniforms for three months during the summer of 2016. We collected spot urine samples for biomonitoring of permethrin metabolites at one week, one month and three months after first use of the LLPI uniform. Following three months of wear, we collected pants and socks and analyzed them for permethrin content and mortality to ticks and mosquitoes. Results Thirteen park employees were included in the analysis. Bioactive amounts of permethrin remained in all clothing swatches tested, although there was great variability. Tick mortality was high, with 78% of pant and 88% of sock swatches having mean knockdown percentages ≥ 85%. In contrast, mosquito mortality was low. Over the study period, the absorbed dosage of permethrin averaged < 4 μg/kg/d of body weight based on measurements of three metabolites. Conclusions LLPI clothing retained permethrin and bioactivity against ticks after three months of use in real-world conditions. The estimated absorbed dosage of permethrin was well below the U.S. EPA level of concern, suggesting that LLPI clothing can be used safely by outdoor workers for tick bite prevention. Electronic supplementary material The online version of this article (10.1186/s13071-019-3314-1) contains supplementary material, which is available to authorized users.