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Abstract Cassava frogskin disease (CFSD) emerged in the Americas in the 1970s, but its causal agent has to date remained a mystery. The clonal propagation of cassava, high incidence of mixed infections, unknown alternative hosts, and root symptoms taking two or more crop cycles to develop, have made it difficult to identify the causal agent. Consequently, most studies on CFSD have produced a catalogue of pathogens occurring in affected plants. Using a sentinel approach, we captured single-pathogen infections in fields with high incidence of root symptoms. Eight months after being exposed to CFSD, we detected

Ticks are blood‐feeding parasites which act as major vectors for various pathogenic microorganisms affecting both animal and human health. Hard ticks are known to move passively (i.e. ‘hitchhike') on migratory birds as they transit between breeding and non‐breeding grounds. This potentially leads to exchange and establishment of non‐endemic tick species in novel environments. However, it is not yet clear if all migratory bird taxa play an equal role in movement of specific tick species, especially outside of medically important tick taxa. To clarify these interactions, we performed a systematic literature review regarding primary data of ticks moving on migratory birds within the African–Western Palearctic flyways. In total, 35 studies were found which showed 123 bird species from 37 families and 12 orders connected to potential movement of 30 tick species representing six genera (Amblyomma, Dermacentor, Haemaphysalis, Hyalomma, Ixodes, Rhipicephalus). Most tick species did not show high abundance for any bird species, or, if they did, only on very few. Only Ixodes ricinus and Hyalomma marginatum were estimated to be carried at above average burdens by multiple bird species. This could indicate an increased likelihood of these species to be moved during migration. Specific tick species or whole genera were only found in certain migratory seasons as expected based on their geographic distributions. Even so, species found in both migratory seasons did not differ in their estimated abundances on birds between seasons. This result could suggest that tick abundance on migrating birds is not always a direct result of geographic distribution and may suggest an understudied importance of stopover sites towards potential tick introduction or turnover. Taken together, the results presented here provide guiding information for future analyses integrating individual level variation into the current understanding of tick movement with migratory birds. [ABSTRACT FROM AUTHOR]

Understanding the role of variation in host resistance and the multitude of transmission modes of parasites infecting hosts with complex behavioral interactions is essential for the control of emerging diseases. We used a discrete stage model to study the invasion dynamics of crayfish plague—an example of a detrimental disease—into a naïve host population that displays within‐population variation in resistance of environmental infections and juvenile classes that are safe from contacts with adults. In the model, infection sources include four age classes of crayfish, contaminated carcasses, and free‐dwelling zoospores. Disease transmission occurs via environment with a threshold infection density and through contacts, cannibalism, and scavenging of disease‐killed conspecifics. Even if the infection is fatal, coexistence of the host and the parasite can be facilitated by variance of resistance and survival of the hiding juveniles. The model can be applied in the control of emerging diseases especially in crayfish‐like organisms. [ABSTRACT FROM AUTHOR]

The article reports the first occurrence of cassava witches' broom disease (CWBD) and Ceratobasidium theobromae in the Americas, specifically in French Guiana. The disease poses a threat to cassava, a vital food source with cultural and economic significance for indigenous communities in the region. The study conducted in 2024 identified symptoms of CWBD in multiple communes, highlighting the urgent need for regional action to address this emerging disease. [Extracted from the article]

This article provides genomic information on the causal agent of Cypress Canker Disease, Seiridium cupressi. The study focuses on two isolates of S. cupressi, BM-138-000515 and BM-138-000234, which were retrieved from the Italian National Research Council. The DNA of these isolates was sequenced using Illumina MiSeq, and the resulting genome assemblies were assessed for quality and completeness. The study also predicted protein coding genes and identified potential effectors. A phylogenomic analysis was conducted to compare S. cupressi with related species. The genome sequences have been deposited in GenBank for public access. [Extracted from the article]

Crimean Congo Hemorrhagic Fever Virus (CCHFV) is the etiological agent of a severe hemorrhagic fever affecting Africa, Asia and southern Europe. In recent decades, climate change has led to an increase in the distribution range of this virus. Little scientific data is yet available on the interactions with its vector, the tick, or on its biology. However, the confirmed presence of human infections in Spain and positive serologies in Corsican livestock could well focus attention on this pathogen. This review takes stock of developments in eco-epidemiological knowledge of this virus, particularly in Europe and especially in France. What about Romania. [ABSTRACT FROM AUTHOR]

To assess the DNA virome associated with air yam (Dioscorea bulbifera L.), leaf samples were collected from plants displaying virus-like symptoms in northeastern Brazil in 2021. Total DNA preparations from PCR positive samples (n = 3) were used as template for viral genome amplification via rolling circle amplification and subjected to high-throughput sequencing. Three Illumina-based full-length badnaviral genomes were recovered from 980 to 30,668 reads and a coverage depth of 33 to 963x. The new genomes ranged from 7,208 to 7,420 bp in size and showed typical badnaviral genomic organization with three main open reading frames (ORFs 1–3). Based on pairwise nucleotide identity using the reverse transcriptase (RT) and ribonuclease H (RNase H) sequences, the newly discovered isolates were identified as dioscorea bacilliform AL virus (DBALV; n = 1) and dioscorea bacilliform SN virus (DBSNV; n = 2), at 85.1–86.6 and 82.2–83.9%, respectively. At least two recombination events were predicted in the DBSNV-DBH isolate, with DBALV- and DBSNV-like sequences identified as putative parents. To our knowledge, these are the first complete genome sequences of yam-infecting badnaviruses described in Brazil. [ABSTRACT FROM AUTHOR]

Oropouche fever is a zoonotic dengue-like syndrome caused by Oropouche virus. In August–September 2020, dengue-like syndrome developed in 41 patients in a remote rainforest village in French Guiana. By PCR or microneutralization, 23 (82.1%) of 28 tested patients were positive for Oropouche virus, documenting its emergence in French Guiana.

Cacao swollen shoot disease (CSSD) is a damaging disease of Theobroma cacao L. associated with infection by a group of poorly characterized badnaviral species. To establish causality and characterize the symptomatology associated with infection by the badnavirus cacao swollen shoot Ghana M virus (CSSGMV), an infectious clone (1.3-mer) was constructed and used to inoculated cacao “Amelonado” seedlings by biolistic inoculation (BI; n = 18) and agroinoculation (AI; n = 15). Newly expanded leaves of BI (10/18) and AI (12/15) plants developed foliar mosaic and curling symptoms 30-days post inoculation (dpi), with chlorotic mottling and necrotic crinkling being evident by 90 dpi. By 120 dpi, three of 15 AI plants exhibited characteristic stem-swelling. Viral infection was verified by PCR-amplification and sequencing of a 1068 bp fragment of the CSSGMV ORF3 from newly expanding leaves 60 dpi. The PCR results indicated that 14 of 18 and 15 of 15 BI and AI plants, respectively, were systemically infected. The complete CSSGMV genome sequence was determined, by Illumina sequencing, from representative AI and BI plants and shared >99.5% pairwise nucleotide identity with CSSGMV-Nig9 (GenBank Accession No. MH785299). Based on the development of characteristic CSSD symptoms and recovery of partial and complete genome sequences of CSSGMV-Nig9 from systemically infected cacao plants, Koch's postulates have been fulfilled.

Oropouche fever is a zoonotic dengue-like syndrome caused by Oropouche virus. In August-September 2020, dengue-like syndrome developed in 41 patients in a remote rainforest village in French Guiana. By PCR or microneutralization, 23 (82.1%) of 28 tested patients were positive for Oropouche virus, documenting its emergence in French Guiana. [ABSTRACT FROM AUTHOR]

[Display omitted] • A LC-MS/MS method with microscale palytoxin oxidation was successfully validated. • High instrumental sensitivity and extract stability was achieved. • The quantitative method includes six palitoxin-like molecules in its scope. • In silico prediction provided solubility information about the main analytes. • Palytoxin ions were detected and confirmed in Haff disease-related samples. Haff disease typically develops after eating contaminated marine or freshwater species, especially fish. Despite still having an unknown etiology, recent reports have suggested its possible correlation with palytoxins. Therefore, the present work aimed to optimize and perform a validation of a sensitive method using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) for the analysis of palytoxin and some of its analogs, with the main purpose of investigating their presence in marine and freshwater food samples associated with Haff disease in Brazil. The method optimization was performed using a central composite rotatable design and fish samples fortified with the palytoxin standard. Then, the optimized method was validated for different food matrices, including freshwater and marine fish, mollusks, and crustaceans. The sample preparation involved a solid–liquid extraction using methanol and water, solid-phase extraction using Strata-X cartridges, and on-column palytoxin oxidation. The detection of the main oxidized fragments (amino and amide aldehydes) was achieved by LC-MS/MS with electrospray ionization in positive mode, using a C18 column, as well as acetonitrile and water as mobile phases, both acidified with 0.1 % of formic acid. After optimization and validation, the etiological investigation involved the analysis of 16 Brazilian Haff disease-related food samples (in natura and leftover meals) from 2022. The method was demonstrated to be appropriate for quantitative analysis of freshwater and marine species. So far, it has proven to be one of the most sensitive methods related to palytoxin detection (LOD 10 μg/kg), being able to work in a range that includes the provisional ingestion limit (30 μg/kg). Regarding the Haff disease-related samples analysis, there is a strong indication of palytoxin contamination since the amino aldehyde (common fragment for all palytoxins) was detected in 15 of the 16 samples. Selected results were confirmed using liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS). [ABSTRACT FROM AUTHOR]

Disease can be a powerful driver of population and community dynamics, as well as evolutionary processes. Disease is also emerging at increasing rates, resulting in massive impacts on populations, communities, and ecosystems. However, assessing these impacts requires foundational knowledge of disease agents and hosts, which is often lacking, particularly in aquatic insects.We describe a recent disease outbreak in caddisflies, suggesting potential consequences for population and community dynamics of the host. We use a series of complementary studies to develop a cohesive foundation of information about this disease, including identification using genomic methods, observational prevalence studies, laboratory experiments to establish transmissibility and fitness consequences, and laboratory and field investigations to infer transmission mechanisms.We identified the infection as being caused by the oomycete Saprolegnia—the first time this parasite has been noted in insect eggs. Prevalence surveys found high prevalence (up to 36%) with variation across space, time, and host species. We demonstrated increasing egg mortality with increasing infection within an egg mass (every 10% increase in infection rate doubles odds of mortality), thereby confirming disease. We established transmissibility and show that transmission occurs through both direct contact with infected egg masses and from background sources, which probably interact to create complex patterns of disease.Taken together, our findings show that conditions necessary for population and community consequences are present. Specifically, increased mortality rates almost certainly occurred during the outbreak, yielding lower larval numbers and potentially altering community interactions. Transmission by contact between egg masses combined with observed species‐specific prevalence suggest shifts in the relative performance of different species because of interactions between host and parasite life histories.Outside extreme examples such as chytrid fungus, disease has traditionally received less interest than resource competition or predation in community ecology, although disease ecology is advancing rapidly. One major hurdle is a lack of foundational knowledge characterising disease processes in natural communities, particularly in aquatic insects. Our findings highlight the importance of investigating diseases in insect eggs and provide the foundation for further investigations of how these processes play out at the population and community scale. [ABSTRACT FROM AUTHOR]

Badnaviruses are plant pararetroviruses that infect economically important crops worldwide, and several badnaviral species have been reported causing significant economic losses in cacao plantations in West Africa. Based on the available full-length genome sequences of cacao swollen shoot disease (CSSD)-associated badnaviruses (n = 66), four primer pairs (CSSD1-CSSD4) were designed to amplify a fragment of the 5′ region of open reading frame (ORF) 3, which comprises the movement protein, by polymerase chain reaction (PCR). Primers were evaluated for their ability to amplify a badnaviral fragment(s) from symptomatic and asymptomatic cacao leaf samples collected in Côte d'Ivoire during 2017–2019. The PCR products obtained by amplification with the CSSD1 primers showed high sequence variability and were phylogenetically related to one of three different badnaviral species, Cacao swollen shoot Togo B virus, Cacao swollen shoot CD virus, and Cacao swollen shoot CE virus, while the CSSD2 and CSSD4 amplicon sequences grouped exclusively with either cacao swollen shoot Togo B virus (CSSTBV) and Cacao swollen shoot Ghana M virus isolates, respectively. The majority of the isolates obtained here were most closely phylogenetically related to CSSTBV, with which they shared 81.0–98.0% nucleotide identity, making the CSSTBV-like isolates the predominant species associated with badnavirus-infected cacao trees tested in Côte d'Ivoire. [ABSTRACT FROM AUTHOR]

An alarming number of global warnings concerning amphibian mortality outbreaks have been released in recent years. Emerging diseases stand out as the main potential causes. Ranavirus is a worldwide-spread highly infectious disease capable of affecting even other ectothermic animals such as fish and reptiles. One major issue regarding this pathology is the lack of clinical signs before it leads up to death. Aiming at having a better understanding of anurans susceptibility, this study analyzed bullfrog (Lithobates catesbeianus) survival rate, when challenged with three doses of a Brazilian strain of Frog Virus 3 (FV3). The qPCR analysis indicated a low infectivity rate in these animals both as larvae and as adults. To elucidate the results, the following hypothesis was performed: 1) The amount of inoculum used on the frogs was insufficient to trigger an infection; 2) For the FV3 to produce clinical signs in this species, there is the need for a cofactor; 3) The animals did undergo FV3 infection but recovered in the course of the experiment, and 4) The inoculum utilized might have been low-virulence. Finally, the presence of actual clinical signs of ranavirus is discussed, with the more likely hypothesis.

The genetic structure of a sample of isolates of the oomycete plant pathogen Phytophthora cinnamomi from natural and agricultural outbreaks and the long-distance movement of individual genotypes were studied using four microsatellite markers to genotype 159 isolates of Californian, Mexican, and worldwide origins. Allelic profiles identified 75 multilocus genotypes. A STRUCTURE analysis placed them in three groups characterized by different geographic and host ranges, different genic and genotypic diversity, and different reproductive modes. When relationships among genotypes were visualized on a minimum spanning network (MSN), genotypes belonging to the same STRUCTURE group were contiguous, with rare exceptions. A putatively ancestral group 1 had high genic diversity, included all A1 mating type isolates and all Papuan isolates in the sample, was rarely isolated from natural settings in California and Mexico, and was positioned at the center of the MSN. Putatively younger groups 2 and 3 had lower genic diversity, were both neighbors to group 1 but formed two distinct peripherical sectors of the MSN, and were equally present in agricultural commodities and natural settings in Mexico and California. A few genotypes, especially in groups 2 and 3, were isolated multiple times in different locations and settings. The presence of identical genotypes from the same hosts in different continents indicated that long-distance human-mediated movement of P. cinnamomi had occurred. The presence of identical genotypes at high frequencies in neighboring wildlands and agricultural settings suggest that specific commodities may have been the source of recent wild infestations caused by novel invasive genotypes. [ABSTRACT FROM AUTHOR]

Natural history museums and the specimen collections they curate are vital scientific infrastructure, a fact as true today as it was when biologists began collecting and preserving specimens over 200 years ago. The importance of museum specimens in studies of taxonomy, systematics, ecology and evolutionary biology is evidenced by a rich and abundant literature, yet creative and novel uses of specimens are constantly broadening the impact of natural history collections on biodiversity science and global sustainability. Excellent examples of the critical importance of specimens come from their use in documenting the consequences of environmental change, which is particularly relevant considering the alarming rate at which we now modify our planet in the Anthropocene. In this review, we highlight the important role of bird, mammal and amphibian specimens in documenting the Anthropocene and provide examples that underscore the need for continued collection of museum specimens. [ABSTRACT FROM AUTHOR]

Natural history museums and the specimen collections they curate are vital scientific infrastructure, a fact as true today as it was when biologists began collecting and preserving specimens over 200 years ago. The importance of museum specimens in studies of taxonomy, systematics, ecology and evolutionary biology is evidenced by a rich and abundant literature, yet creative and novel uses of specimens are constantly broadening the impact of natural history collections on biodiversity science and global sustainability. Excellent examples of the critical importance of specimens come from their use in documenting the consequences of environmental change, which is particularly relevant considering the alarming rate at which we now modify our planet in the Anthropocene. In this review, we highlight the important role of bird, mammal and amphibian specimens in documenting the Anthropocene and provide examples that underscore the need for continued collection of museum specimens. [ABSTRACT FROM AUTHOR]

Oropouche virus is the aetiological agent of Oropouche fever, a zoonotic disease mainly transmitted by midges of the species Culicoides paraensis . Although the virus was discovered in 1955, more attention has been given recently to both the virus and the disease due to outbreaks of Oropouche fever in different areas of Brazil and Peru. Serological studies in human and wild mammals have also found Oropouche virus in Argentina, Bolivia, Colombia, and Ecuador. Several mammals act as reservoirs of the disease, although the sylvatic cycle of Oropouche virus remains to be assessed properly. Oropouche fever lacks key symptoms to be differentiated from other arboviral febrile illnesses from the Americas. Sporadic cases of aseptic meningitis have also been described with good prognosis. Habitat loss can increase the likelihood of Oropouche virus emergence in the short-term in South America. [ABSTRACT FROM AUTHOR]

Senecavirus A (SVA) is a positive-sense single-stranded RNA virus that belongs to the Senecavirus genus within the Picornaviridae family. The virus has been silently circulating in pig herds of the USA since 1988. However, cases of senecavirus-associated vesicular disease were reported in Canada in 2007 and in the USA in 2012. Since late 2014 and early 2015, an increasing number of senecavirus outbreaks have been reported in pigs in different producing categories, with this virus being detected in Brazil, China, and Thailand. Considering the novel available data on senecavirus infection and disease, 2015 may be a divisor in the epidemiology of the virus. Among the aspects that reinforce this hypothesis are the geographical distribution of the virus, the affected pig-producing categories, clinical signs associated with the infection, and disease severity. This review presents the current knowledge regarding the senecavirus infection and disease, especially in the last two years. Senecavirus epidemiology, pathogenic potential, host immunological response, diagnosis, and prophylaxis and control measures are addressed. Perspectives are focused on the need for complete evolutionary, epidemiological and pathogenic data and the capability for an immediate diagnosis of senecavirus infection. The health risks inherent in the swine industry cannot be neglected. [ABSTRACT FROM AUTHOR]

The aquatic gastropod mollusc, Pyrgophorus coronatus, may perform an important role in the transmission of an emergent ocular pathology among fishes in Lake Apoyo, Nicaragua. This disease emerged after an introduction of tilapia (Oreochromis niloticus) and the subsequent loss of Chara sp. beds in the lake. We compared the mollusc population densities in three habitats (sandy/muddy substrates, rocks, and Chara vegetation) at varying depths (1.5, 10, 20, and 30 m) in two volcanic crater lakes in Nicaragua: Lake Apoyo and Lake Xiloa, where lower numbers of affected fishes were found and tilapia has not been introduced. Duplicate samples at 1.5 m depth were taken in each habitat monthly for a year, and triplicate samples for bathymetric analysis of snail populations were performed during August, 2005. Samples of fixed surface area were filtered in a 0.4 cm size screen and live snails were counted from each sample. The preferred snail habitat in both lakes, Chara beds, was vastly reduced in Lake Apoyo via consumption by introduced Nile tilapia (Oreochromis niloticus). Structureless sandy substrates (mean ± standard error 3.1±1.3 ind/m²) had lower population densities than other habitats in Lake Xiloá (rocks 590.9±185.3 ind/m²; vegetation 3 686.5±698.2 ind/m2; ANOVA I, pEl gasterópodo acuático, Pyrgophorus coronatus, podría jugar un papel importante en la transmisión de una patología ocular emergente entre los peces de la laguna de Apoyo, Nicaragua. Esta enfermedad surgió después de una introducción de tilapia (Oreochromis niloticus) y la subsecuente pérdida de lechos de Chara sp. en la laguna. Comparamos las densidades poblacionales del caracol en tres hábitats (substratos arenosos/lodosos, rocas y vegetación de Chara) en dos lagunas cratéricas volcánicas en Nicaragua: La laguna de Apoyo y la laguna de Xiloá, donde no se encuentraron grandes cantidades de peces afectados y donde no se han introducido tilapias. Mensualmente, por un año tomamos muestras duplicadas a 1.5 m profundidad mensualmente por un año, y durante agosto de 2005, muestreos triplicados de las poblaciones del molusco, para análisis batimétrico (1.5, 10, 20 y 30 m). Para determinar el número de individuos por unidad de área superficial, las muestras fueron filtradas en un colador de 0.4 cm de apertura de malla y contamos los moluscos vivos en cada muestra. El hábitat preferido de los caracoles en ambas lagunas fue la vegetación de Chara, que en la laguna de Apoyo fue vastamente reducida al ser consumida por las tilapias nilóticas introducidas (Oreochromis niloticus). Los substratos arenosos, menos estructurados que los otros sustratos estudiados, tuvieron densidades poblacionales más bajas (media ± error estándar 3.1±1.3 ind/m²) que en los otros hábitats en la laguna de Xiloá (vegetation 590.9±185.3 ind/m²; rocas 3 686.5±698.2 ind/m²; ANOVA I, p

Invasive pathogens can cause considerable damage to forest ecosystems. Lack of coevolution is generally thought to enable invasive pathogens to bypass the defence and/or recognition systems in the host. Although mostly true, this argument fails to predict intermittent outcomes in space and time, underlining the need to include the roles of the environment and the phenotype in host-pathogen interactions when predicting disease impacts. We emphasize the need to consider host-tree imbalances from a phenotypic perspective, considering the lack of coevolutionary and evolutionary history with the pathogen and the environment, respectively. We describe how phenotypic plasticity and plastic responses to environmental shifts may become maladaptive when hosts are faced with novel pathogens. The lack of host-pathogen and environmental coevolution are aligned with two global processes currently driving forest damage: globalization and climate change, respectively. We suggest that globalization and climate change act synergistically, increasing the chances of both genotypic and phenotypic imbalances. Short moves on the same continent are more likely to be in balance than if the move is from another part of the world. We use Gremmeniella abietina outbreaks in Sweden to exemplify how host-pathogen phenotypic interactions can help to predict the impacts of specific invasive and emergent diseases. [ABSTRACT FROM AUTHOR]

Abstract: In order to put a halt to the Bluetongue virus serotype 8 (BTV-8) epidemic in 2008, the European Commission promoted vaccination at a transnational level as a new measure to combat BTV-8. Most European member states opted for a mandatory vaccination campaign, whereas the Netherlands, amongst others, opted for a voluntary campaign. For the latter to be effective, the farmer's willingness to vaccinate should be high enough to reach satisfactory vaccination coverage to stop the spread of the disease. This study looked at a farmer's expected utility of vaccination, which is expected to have a positive impact on the willingness to vaccinate. Decision analysis was used to structure the vaccination decision problem into decisions, events and payoffs, and to define the relationships among these elements. Two scenarios were formulated to distinguish farmers’ mindsets, based on differences in dairy heifer management. For each of the scenarios, a decision tree was run for two years to study vaccination behaviour over time. The analysis was done based on the expected utility criterion. This allows to account for the effect of a farmer's risk preference on the vaccination decision. Probabilities were estimated by experts, payoffs were based on an earlier published study. According to the results of the simulation, the farmer decided initially to vaccinate against BTV-8 as the net expected utility of vaccination was positive. Re-vaccination was uncertain due to less expected costs of a continued outbreak. A risk averse farmer in this respect is more likely to re-vaccinate. When heifers were retained for export on the farm, the net expected utility of vaccination was found to be generally larger and thus was re-vaccination more likely to happen. For future animal health programmes that rely on a voluntary approach, results show that the provision of financial incentives can be adjusted to the farmers’ willingness to vaccinate over time. Important in this respect are the decision moment and the characteristics of the disease. Farmers’ perceptions of the disease risk and about the efficacy of available control options cannot be neglected. [Copyright &y& Elsevier]

Culicoides vectors can transmit a diverse array of parasites and are globally distributed. We studied feeding preferences and seasonal variation of Culicoides (Diptera: Ceratopogonidae) vectors in an urban forest of Germany to determine whether humans living nearby are readily exposed to vector-borne parasites from wild animals. We used a fragment of the mtDNA COI gene to identify hosts from blood meals. We amplified a fragment of the mtDNA cyt b to detect haemosporidian infections in Culicoides abdomens and thoraxes. We detected a total of 22 Culicoides species. Fifty-eight blood meals (84%) were from humans, 10 from birds, and one from livestock. We found Culicoides kibunensis (considered ornithophilic) with 29 human blood meals. Host generalist Culicoides festivipennis and Culicoides obsoletus had 14 human blood meals. Culicoides clastrieri and Culicoides semimaculatus fed on birds; previously humans were their only known host. Six thoraxes and three abdomens were infected with either Haemoproteus pallidulus or Haemoproteus parabelopolskyi. There were changes in Culicoides community structure across months. Culicoides pictipennis was the dominant species during spring, C. kibunensis and C. clastrieri were dominant during summer, and C. obsoletus was dominant by early autumn. All dominant species were generalists feeding on birds, livestock and humans. Our results indicate that humans can serve as a blood source for dominant Culicoides species instead of the normal wild animal hosts in urban areas. [ABSTRACT FROM AUTHOR]

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Dispersal is a key parameter of adaptation, invasion and persistence. Yet standard population genetics inference methods hardly distinguish it from drift and many species cannot be studied by direct mark-recapture methods. Here, we introduce a method using rates of change in cline shapes for neutral markers to estimate contemporary dispersal. We apply it to the devastating banana pest Mycosphaerella fijiensis, a wind-dispersed fungus for which a secondary contact zone had previously been detected using landscape genetics tools. By tracking the spatio-temporal frequency change of 15 microsatellite markers, we find that σ, the standard deviation of parent-offspring dispersal distances, is 1.2 km/generation1/2. The analysis is further shown robust to a large range of dispersal kernels. We conclude that combining landscape genetics approaches to detect breaks in allelic frequencies with analyses of changes in neutral genetic clines offers a powerful way to obtain ecologically relevant estimates of dispersal in many species. [ABSTRACT FROM AUTHOR]

For thousands of years, humans have recognized connections between the environment and outbreaks of disease. In recent years, anthropogenic changes to ecosystems have also been linked to changes in wildlife diseases, some of which are zoonotic. Wildlife rehabilitators are frequently the first to observe emergent diseases or changes in the routine presentation of known disease. As a result, it is important for wildlife rehabilitators to stay current on disease trends. This paper reviews available literature to provide an overview of the impact of anthropogenic changes on wildlife disease as well as the need for information sharing among wildlife professionals. [ABSTRACT FROM AUTHOR]

Landscape genetics, which combines population genetics, landscape ecology and spatial statistics, has emerged recently as a new discipline that can be used to assess how landscape features or environmental variables can influence gene flow and spatial genetic variation. We applied this approach to the invasive plant pathogenic fungus Mycosphaerella fijiensis, which causes black leaf streak disease of banana. Around 880 isolates were sampled within a 50 × 50 km area located in a fragmented banana production zone in Cameroon that includes several potential physical barriers to gene flow. Two clustering algorithms and a new F-based procedure were applied to define the number of genetic entities and their spatial domain without a priori assumptions. Two populations were clearly delineated, and the genetic discontinuity appeared sharp but asymmetric. Interestingly, no landscape features matched this genetic discontinuity, and no isolation by distance (IBD) was found within populations. Our results suggest that the genetic structure observed in this production area reflects the recent history of M. fijiensis expansion in Cameroon rather than resulting from contemporary gene flow. Finally, we discuss the influence of the suspected high effective population size for such an organism on (i) the absence of an IBD signal, (ii) the characterization of contemporary gene-flow events through assignation methods of analysis and (iii) the evolution of the genetic discontinuity detected in this study. [ABSTRACT FROM AUTHOR]

Dispersal processes of fungal plant pathogens can be inferred from analysis of spatial genetic structures resulting from recent range expansion. The relative importance of long-distance dispersal (LDD) events vs. gradual dispersal in shaping population structures depends on the geographical scale considered. The fungus Mycosphaerella fijiensis, pathogenic on banana, is an example of a recent worldwide epidemic. Founder effects in this species were detected at both global and continental scale, suggesting stochastic spread of the disease through LDD events. In this study, we analysed the structure of M. fijiensis populations in two recently (∼1979–1980) colonized areas in Costa Rica and Cameroon. Isolates collected in 10–15 sites distributed along a ∼250- to 300- km-long transect in each country were analysed using 19 microsatellite markers. We detected low-to-moderate genetic differentiation among populations in both countries and isolation by distance in Cameroon. Combined with historical data, these observations suggest continuous range expansion at the scale of banana-production area through gradual dispersal of spores. However, both countries displayed specific additional signatures of colonization: a sharp discontinuity in gene frequencies was observed along the Cameroon transect, while the Costa Rican populations seemed not yet to have reached genetic equilibrium. These differences in the genetic characteristics of M. fijiensis populations in two recently colonized areas are discussed in the light of historical data on disease spread and ecological data on landscape features. [ABSTRACT FROM AUTHOR]

Abstract: Hendra virus (HeV) and Nipah virus (NiV) are recently-emerged, closely related and highly pathogenic paramyxoviruses. We have analysed here the pathogenesis of the acute HeV infection using the new animal model, golden hamster (Mesocricetus auratus), which is highly susceptible to HeV infection. HeV-specific RNA and viral antigens were found in multiple organs and virus was isolated from different tissues. Dual pathogenic mechanism was observed: parenchymal infection in various organs, including the brain, with vasculitis and multinucleated syncytia in many blood vessels. Furthermore, monoclonal antibodies specific for the NiV fusion protein neutralized HeV in vitro and efficiently protected hamsters from HeV if given before infection. These results reveal the similarities between HeV and NiV pathogenesis, particularly in affecting both respiratory and neuronal system. They demonstrate that hamster presents a convenient novel animal model to study HeV infection, opening new perspectives to evaluate vaccine and therapeutic approaches against this emergent infectious disease. [Copyright &y& Elsevier]