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Immune responses to vaccination are heterogeneous between individuals; the same vaccine that provides protection in one circumstance may be ineffective in another. One factor that could influence the response to vaccination is concurrent or prior infection with unrelated parasites. Here, we review both the experimental and epidemiological literature on parasite-vaccine interactions, and present a meta-analysis of the published data. In total, our review returned 101 relevant articles, 50 of which met criteria for meta-analysis. Parasite factors potentially affecting vaccination include the type of parasite involved, the stage of infection, and the timing of infection relative to vaccination. Vaccine factors affecting likelihood of interference by parasites include vaccine formulation, route of administration, and the type of immune response required to provide protection against the target antigen. Our meta-analysis of these data show three key things: (1) parasite infections at the time of vaccination result in worse immunisation outcomes, (2) chronic helminth infections are more likely to negatively impact immunisation than acute helminth infections, and (3) thymus-dependent vaccines are more susceptible to parasite interference than thymus-independent vaccines. Our findings highlight the importance of considering and mitigating parasite infections: by taking parasites into account, it should be possible to more effectively immunise individuals and populations. [ABSTRACT FROM AUTHOR]

The ongoing West African Ebola epidemic highlights a recurring trend in the zoonotic emergence of virulent pathogens likely to come from bat reservoirs that has caused epidemiologists to ask ‘Are bats special reservoirs for emerging zoonotic pathogens?’ We collate evidence from the past decade to delineate mitochondrial mechanisms of bat physiology that have evolved to mitigate oxidative stress incurred during metabolically costly activities such as flight. We further describe how such mechanisms might have generated pleiotropic effects responsible for tumor mitigation and pathogen control in bat hosts. These synergisms may enable ‘special’ tolerance of intracellular pathogens in bat hosts; paradoxically, this may leave them more susceptible to immunopathological morbidity when attempting to clear extracellular infections such as ‘white-nose syndrome’ (WNS). [ABSTRACT FROM AUTHOR]

Do stress hormones, such as corticosterone, enhance bird susceptibility to mosquitoes in ways that enhance rates of co-infection? Does this then enhance pathogen emergence? [ABSTRACT FROM AUTHOR]

The notion that climate change will generally increase human and wildlife diseases has garnered considerable public attention, but remains controversial and seems inconsistent with the expectation that climate change will also cause parasite extinctions. In this review, we highlight the frontiers in climate change–infectious disease research by reviewing knowledge gaps that make this controversy difficult to resolve. We suggest that forecasts of climate-change impacts on disease can be improved by more interdisciplinary collaborations, better linking of data and models, addressing confounding variables and context dependencies, and applying metabolic theory to host–parasite systems with consideration of community-level interactions and functional traits. Finally, although we emphasize host–parasite interactions, we also highlight the applicability of these points to climate-change effects on species interactions in general. [ABSTRACT FROM AUTHOR]

Recent efforts to include parasites in food webs have drawn attention to a previously ignored facet of foraging ecology: parasites commonly function as prey within ecosystems. Because of the high productivity of parasites, their unique nutritional composition and their pathogenicity in hosts, their consumption affects both food-web topology and disease risk in humans and wildlife. Here, we evaluate the ecological, evolutionary and epidemiological significance of feeding on parasites, including concomitant predation, grooming, predation on free-living stages and intraguild predation. Combining empirical data and theoretical models, we show that consumption of parasites is neither rare nor accidental, and that it can sharply affect parasite transmission and food web properties. Broader consideration of predation on parasites will enhance our understanding of disease control, food web structure and energy transfer, and the evolution of complex life cycles. [Copyright &y& Elsevier]

Historically, the role of parasites in ecosystem functioning has been considered trivial because a cursory examination reveals that their relative biomass is low compared with that of other trophic groups. However there is increasing evidence that parasite-mediated effects could be significant: they shape host population dynamics, alter interspecific competition, influence energy flow and appear to be important drivers of biodiversity. Indeed they influence a range of ecosystem functions and have a major effect on the structure of some food webs. Here, we consider the bottom-up and top-down processes of how parasitism influences ecosystem functioning and show that there is evidence that parasites are important for biodiversity and production; thus, we consider a healthy system to be one that is rich in parasite species. [Copyright &y& Elsevier]

Concentrated monoclonal antibody (mAb) solutions can lead to high viscosity as a result of protein-protein interactions and pose challenges for manufacture. Dipicolinic acid (DPA, pyridine-2,6-dicarboxylic acid) is a potential excipient for reduction of protein solution viscosity and here we describe new DPA salts with improved aqueous solubility. Crystallinity and solubility screens identified ethanolamine and diethanolamine as two promising counterions which generated crystalline, high melting point, anhydrous salt forms of DPA at 2:1 M stoichiometry. These salts significantly reduced the solution viscosity of five mAbs, equal to or better than that for the addition of arginine hydrochloride at equivalent osmolality. The presence of the DPA salts in solution did not significantly perturb the melting point of the mAbs, as determined by calorimetry, indicating an absence of any destabilization of protein conformation. Addition of the DPA salts to the mAb solutions stored at 5 °C over 6 months did not cause additional loss of the monomer fraction, though evidence of increased aggregation and fragmentation for three of the five mAbs was observed during 40 °C (accelerated and stressed) storage. Overall, this study demonstrates that ethanolamine-DPA and diethanolamine-DPA can serve as two novel excipients for viscosity reduction and could be considered by formulation scientists when developing highly concentrated mAb formulations. [ABSTRACT FROM AUTHOR]

Abstract: Governments and NGOs worldwide aim to develop models of tourism that realize the economic, environmental, and cultural ideals of ecotourism. This is true in the national parks of the Northern Safari Circuit of Tanzania, which attract hundreds of thousands of tourists annually. To better understand what tourists to Tanzania were willing to pay for various attributes of their tour package, we used a linear mixed effects model to analyze what attributes of 72 tour packages from 32 tour operators contributed to the price of tour packages. We found that the number of days spent on tour, the number of days spent in the Serengeti, the type of accommodation (basic camping versus lodges or luxury tents), the mode of transport into the park (flying versus driving), and the inclusion of cultural tourism helped predict the price of a tour package. Our findings suggest that tour operators charge 92% more for a day in the Serengeti than other Northern Circuit attractions, but we do not examine what happens to the additional rent generated by the Serengeti. Additionally, the utility of cultural tourism in attracting foreign tourists presents both tremendous opportunities and potential challenges to efforts to realize culturally sensitive ecotourism. [ABSTRACT FROM AUTHOR]

Molecular-based approaches might be misleading for assessing the ‘potential importance’ of possible reservoirs for parasites unless used in conjunction with population dynamics and ecological studies that provide an understanding of the linkages between the enzootic transmission cycle (in wild animals) and that in domestic animals. Better understanding of ecological constraints on Leishmania transmission is needed to assess fully the passage of the parasite between its sandfly vector and different mammalian host species. We use a straightforward mathematical framework to illustrate that misuse of association patterns, as guidance for implementation of control measures, can in fact increase the endemism of leishmaniasis. [Copyright &y& Elsevier]

Cholera dynamics in endemic regions display regular seasonal cycles and pronounced interannual variability. We review here the current quantitative evidence for the influence of climate on cholera dynamics with reference to the early literature on the subject. We also briefly review the incipient status of mathematical models for cholera and argue that these models are important for understanding climatic influences in the context of the population dynamics of the disease. A better understanding of disease risk related to the environment should further underscore the need for changing the socioeconomic conditions conducive to cholera. [Copyright &y& Elsevier]

Madagascar is home to three endemic species of Old World Fruit Bat, which are important pollinators and seed dispersers. We aimed to quantitatively assess population trajectories for the two largest of these species, the IUCN-listed 'Vulnerable' Eidolon dupreanum and Pteropus rufus. To this end, we conducted a longitudinal field study, in which we live-captured E. dupreanum and P. rufus , estimated species-specific fecundity rates, and generated age-frequency data via histological analysis of cementum annuli layering in tooth samples extracted from a subset of individuals. We fit exponential models to resulting data to estimate annual survival probabilities for adult bats (s A =.794 for E. dupreanum ; s A =.511 for P. rufus), then applied Lefkovitch modeling techniques to infer the minimum required juvenile survival rate needed to permit longterm population persistence. Given estimated adult survival, population persistence was only possible for E. dupreanum when field-based fecundity estimates were replaced by higher values reported in the literature for related species. For P. rufus , tooth-derived estimates of adult survival were so low that even assumptions of perfect (100%) juvenile annual survival would not permit stable population trajectories. Age-based survival analyses were further supported by longitudinal exit counts carried out from 2013 to 2018 at three local P. rufus roost sites, which demonstrated a statistically significant, faintly negative time trend, indicative of subtle regional population declines. These results suggest that Malagasy fruit bat species face significant threats to population viability, with P. rufus particularly imperiled. Immediate conservation interventions, including habitat restoration and cessation of legally sanctioned bat hunting, are needed to protect Madagascar's fruit bats into the future. [ABSTRACT FROM AUTHOR]

Our aim in conducting annual horizon scans is to identify issues that, although currently receiving little attention, may be of increasing importance to the conservation of biological diversity in the future. The 15 issues presented here were identified by a diverse team of 22 experts in horizon scanning, and conservation science and its application. Methods for identifying and refining issues were the same as in two previous annual scans and are widely transferable to other disciplines. The issues highlight potential changes in climate, technology and human behaviour. Examples include warming of the deep sea, increased cultivation of perennial grains, burning of Arctic tundra, and the development of nuclear batteries and hydrokinetic in-stream turbines. [ABSTRACT FROM AUTHOR]

This review describes outcomes of a 2010 horizon-scanning exercise building upon the first exercise conducted in 2009. The aim of both horizon scans was to identify emerging issues that could have substantial impacts on the conservation of biological diversity, and to do so sufficiently early to encourage policy-relevant, practical research on those issues. Our group included professional horizon scanners and researchers affiliated with universities and non- and inter-governmental organizations, including specialists on topics such as invasive species, wildlife diseases and coral reefs. We identified 15 nascent issues, including new greenhouse gases, genetic techniques to eradicate mosquitoes, milk consumption in Asia and societal pessimism. [ABSTRACT FROM AUTHOR]

Abstract: In early 1994, a novel strain of Mycoplasma gallisepticum (MG)—a poultry pathogen with a world-wide distribution—emerged in wild house finches and within 3 years had reached epidemic proportions across their eastern North American range. The ensuing epizootic resulted in a rapid decline of the host population coupled with considerable seasonal fluctuations in prevalence. To understand the dynamics of this disease system, a multi-disciplinary team composed of biologists, veterinarians, microbiologists and mathematical modelers set forth to determine factors driving and influenced by this host–pathogen system. On a broad geographic scale, volunteer observers (“citizen scientists”) collected and reported data used for calculating both host abundance and disease prevalence. The scale at which this monitoring initiative was conducted is unprecedented and it has been an invaluable source of data for researchers at the Cornell Laboratory of Ornithology to track the spread and magnitude of disease both spatially and temporally. At a finer scale, localized and intensive field studies provided data used to quantify the effects of disease on host demographic parameters via capture–mark–recapture modeling, effects of host behavior on disease and vice-versa, and the biological and genetic profiles of birds with known phenotypic characteristics. To balance the field-based component of the study, experiments were conducted with finches held in captivity to describe and quantify the effects of experimental infections on hosts in both individual and social settings. The confluence of these various elements of the investigation provided the foundation for construction of a general compartmentalized epidemiological model of the dynamics of the house finch–MG system. This paper serves several purposes including (i) a basic review of the pathogen, host, and epidemic cycle; (ii) an explanation of our research strategy; (iii) a basic review of results from the diverse multi-disciplinary approaches employed; and (iv) pertinent questions relevant to this and other wildlife disease studies that require further investigation. [Copyright &y& Elsevier]

Reducing threats to biodiversity is the key objective of ranger patrols in protected areas. However, efforts can be hampered by rangers' inability to detect threats, and poor understanding of threat abundance and distribution in a landscape. Snares are particularly problematic due to their cryptic nature and limited selectivity with respect to captured animals' species, sex, or age. Using an experimental approach, we investigated the effect of search effort, habitat, season, and team on rangers' detection of snares in a tropical forest landscape. We provide an effort-detection curve, and use our findings to make preliminary predictions about snare detection under different scenarios of patrol effort. Results suggest that the overall probability of a searcher detecting any given snare in a 0.25/km2 area, assuming 60 min (or approximately 2 km) of search effort is 20% (95% CI ± 15–25%), with no significant effect of season, habitat or team. Our models suggested this would increase by approximately 10% with an additional 30mins/1 km of search effort. Our preliminary predictions of the effectiveness of different patrolling scenarios show that detection opportunities are maximised at low effort levels by deploying multiple teams to a single area, but at high effort levels deploying single teams becomes more efficient. Our results suggest that snare detectability in tropical forest landscapes is likely to be low, and may not improve dramatically with increased search effort. Given this, managers need to consider whether intensive snare-removal efforts are the best use of limited resources; the answer will depend on their underlying objectives. [ABSTRACT FROM AUTHOR]