Experimental Evidence for Reduced Rodent Diversity Causing Increased Hantavirus Prevalence

Emerging and re-emerging infectious diseases have become a major global environmental problem with important public health, economic, and political consequences. The etiologic agents of most emerging infectious diseases are zoonotic, and anthropogenic environmental changes that affect wildlife communities are increasingly implicated in disease emergence and spread. Although increased disease incidence has been correlated with biodiversity loss for several zoonoses, experimental tests in these systems are lacking. We manipulated small-mammal biodiversity by removing non-reservoir species in replicated field plots in Panama, where zoonotic hantaviruses are endemic. Both infection prevalence of hantaviruses in wild reservoir (rodent) populations and reservoir population density increased where small-mammal species diversity was reduced. Regardless of other variables that affect the prevalence of directly transmitted infections in natural communities, high biodiversity is important in reducing transmission of zoonotic pathogens among wildlife hosts. Our results have wide applications in both conservation biology and infectious disease management

Defining new pathways to manage the ongoing emergence of bat rabies in Latin America

Rabies transmitted by common vampire bats (Desmodus rotundus) has been known since the early 1900s but continues to expand geographically and in the range of species and environments affected. In this review, we present current knowledge of the epidemiology and management of rabies in D. rotundus and argue that it can be reasonably considered an emerging public health threat. We identify knowledge gaps related to the landscape determinants of the bat reservoir, reduction in bites on humans and livestock, and social barriers to prevention. We discuss how new technologies including autonomously-spreading vaccines and reproductive suppressants targeting bats might manage both rabies and undesirable growth of D. rotundus populations. Finally, we highlight widespread under-reporting of human and animal mortality and the scarcity of studies that quantify the efficacy of control measures such as bat culling. Collaborations between researchers and managers will be crucial to implement the next generation of rabies management in Latin America

Diversidad, historia natural y conservación de los mamíferos de San Vito de Coto Brus, Costa Rica

Aunque Costa Rica ha sido biológicamente bien estudiada, pocas áreas tiene inventarios de mamíferos completos y actualizados, lo que es para llevar a cabo estudios ecológicos y de conservación. La región de San Vito es considerada entre las mas importantes para la investigación científica en el país, debido a la presencia del Jardín Botánico Wilson y la Estación Biológica Las Cruces. Sin embargo, el conocimiento de la mastofauna es incompleto. Por lo tanto se evaluó intensamente los mamíferos de San Vito, y se compiló una lista de especies, con una evaluación de su composición, abundancia relativa, distribución en los habitats, y su estado de conservación. Se registraron 105 especies, que representaron a 85 géneros, 29 familias y 10 órdenes. Los mamíferos no voladores representaron 62 especies, 59 géneros, 23 familias y 9 órdenes. Los murciélagos pertenecieron a 6 familias, 26 géneros y 43 especies. La extensa deforestación y cacería son factores que han causado la extinción local de 7especies, pero la región todavía mantiene un número relativamente alto de su diversidad original, incluyendo a especie raras. Pocas especies fueron comunes o abundantes. La riqueza de especies fue alta en el bosque y los fragmentos de bosque, y más baja en las plantaciones de café, pastizales inducidos y vegetación secundaria. Alrededor del 21% (13) de las espcies estan incluidad en el libro rojo de la UICN. Tres especies (Saimiri oerstedii, Tapirus bairdii y Sylvilagus dicei) son consideradas en peligro y dos (Myrmecophaga trydactila y Caluromys derbianus) como amenazadas: de estas, dos especies (T. bairdii and M. trydactila) se encuentran localmente extintas. Las otras especies son consideradas de bajo riesgo (i.e. Chironectes minimus) o con poca información (i.e. Lontra longicaudis). Adicionalmente, 24 especies (39%) están incluidas en CITES

Avaliação de zonas húmidas superficiais, tropicais e semiáridas associadas ao botulismo aviar

[Introduction]: Shallow wetlands are important for waterfowl; they are currently affected by climatic changes and nutrients derived from agriculture. This situation has been associated with outbreaks of avian botulism. [Objective]: Identify changes in wetlands that can lead to botulism outbreaks, and identify the source of nutrients that may contribute to a eutrophic state. [Methodology]: Evaluation of biotic characteristics (diversity of zooplankton and macroinvertebrates) and physicochemical characteristics (dissolved oxygen, temperature, total dissolved solids, and transparency) in three shallow wetlands (Silva, Coyote, and Trancas) in central Mexico, as well as evaluation of values of stable isotopes of carbon (δ13C) and nitrogen (δ15N) from organisms to detect the input of nutrients to the aquatic ecosystem. [Results]: There was a decrease in transparency, water levels, and zooplankton and invertebrate diversity at all three sites. The values of dissolved oxygen, temperature, and total dissolved solids were different in the three sites. Values of stable carbon (δ13C) and nitrogen (δ15N) isotopes from Silva and Coyote organisms coincide with values of stable isotopes found in sewage, fertilizers, and grains such as corn and wheat. [Conclusion]: Wetlands in the study site registered biotic and physicochemical changes along the year. In Silva and Coyote, water fluctuations, human activities, and, finally, the arrival of thousands of migratory birds produce an accumulation of dead organic matter and nutrients that made the system eutrophic and therefore more prone to present recurrent avian botulism outbreaks.[Introducción]: Los humedales someros son relevantes para las aves acuáticas, actualmente son afectados por el cambio climático y las actividades humanas, esto se ha relacionado con brotes de botulismo aviar. [Objetivo]: Identificar cambios bióticos y fisicoquímicos en los humedales que podrían propiciar brotes de botulismo. Identificar fuentes de nutrientes que contribuyen a un estado eutrófico. [Metodología]: Evaluación de características bioticas (diversidad de zooplancton y macroinvertebrados) y fisicoquímicas (oxígeno disuelto, temperatura, solidos disueltos totales y transparencia) en 3 humedales (Trancas, Coyote y Silva) del centro de México. Identificación de la fuente de nutrientes mediante un análisis isotópico (δ13C y δ15N) de los organismos acuáticos. [Resultados]: Después de la época de lluvias hubo una disminución en la diversidad de zooplancton e invertebrados, así como disminución del nivel y transparencia del agua en los sitios estudiados. Los valores de oxígeno disuelto, temperatura y sólidos disueltos totales fueron diferentes en los 3 sitios. Los valores de los isótopos estables de carbono (δ13C) y nitrógeno (δ15N) de los organismos de Silva y Coyote, coinciden con valores de aguas negras, fertilizantes, maíz y trigo. [Conclusión]: Los humedales estudiados registraron cambios bióticos y fisicoquímicos a lo largo del periodo de estudio. En Silva y Coyote las fluctuaciones en el nivel del agua, las actividades humanas y la llegada de miles de aves acuáticas migratorias provocan una acumulación de materia orgánica en descomposición y nutrientes que vuelven a estos sitios eutróficos y propensos a tener brotes recurrentes de botulismo aviar.[Introdução]: As zonas húmidas superficiais são muito importantes para as aves aquáticas, são atualmente afetadas pelas alterações climáticas e as atividades humanas, o que tem sido associado a surtos de botulismo aviar.  [Objetivo]: Identificar alterações bióticas e físico-químicas nas zonas húmidas que possam provocar surtos de botulismo. Identificar fontes de nutrientes que contribuem para um bom estado. [Metodologia]: Avaliação das características bioquímicas (diversidade de zooplâncton e macro invertebrados) e físico-químicas (oxigênio dissolvido, temperatura, soldos dissolvidos totais e transparência) em três zonas úmidas (Trancas, Coyote e Silva) do centro do México. Identificação da fonte de nutrientes através de uma análise isotópica (δ13C e δ15N) dos organismos aquáticos.  [Resultados]: Após a época das chuvas, houve diminuição da diversidade de zooplâncton e invertebrados, bem como diminuição do nível e transparência da água nos três locais. Os valores de oxigênio dissolvido, temperatura e sólidos dissolvidos totais foram diferentes nos três locais. Os valores dos isótopos estáveis de carbono (δ13C) e de N (δ15N) dos organismos de Silva e Coyote correspondem aos valores de águas negras, fertilizantes, milho e trigo. [Conclusão] As três zonas húmidas registraram alterações bióticas e físico-químicas ao longo do período de estudo. Em Silva e Coyote as flutuações no nível da água, as atividades humanas e a chegada de milhares de aves aquáticas migratórias provocam acúmulo de matéria orgânica em decomposição e nutrientes que retornam a esses locais eutróficos e propensos a surtos recorrentes de botulismo aviar

Data from: Macroecology of birds potentially susceptible to the West Nile Virus

Zoonotic diseases transmitted by wildlife affect biological conservation, public and animal health, and the economy. Current research efforts are aimed at finding wildlife pathogens at a given location. However, a meta-analytical approach may reveal emerging macroecological patterns in the host-pathogen relationship at different temporal and spatial scales. West Nile Virus (WNV) is a pathogen with worldwide detrimental impacts on bird populations. To understand macroecological patterns driving WNV infection, we aimed to recognise unknown competent reservoirs using three disease metrics serological prevalence (SP), molecular prevalence (MP) and mortality (M) and test if these metrics are correlated with the evolutionary history, geographical origin of bird species, viral strain, time-space, and methodology. We performed a quantitative review of field studies on birds sampled for WNV. We obtained 4945 observations of 949 species from 39 countries. Our analysis supported the idea that MP and M are good predictors of reservoir competence and allowed us to identify potential competent reservoirs. Furthermore, results indicated that the variability of these metrics was attributable to phylogenetic, time-space, and sample size. A macroecological approach is needed to recognise susceptible species and competent reservoirs and to identify other factors driving zoonotic diseases originating from wildlife

Appendix 1. Database of birds tested to WNV

The database is a compilation of worldwide studies of birds sampled for West Nile Virus through diagnostic techniques of serology and molecular biology. Each observation includes an ID that is associated with the information of the original study. The database consists of 147 published studies including 4995 records which ranged from the years 1959 to 2017 and represented 39 countrie

Assessing Sustainability in Cattle Silvopastoral Systems in the Mexican Tropics Using the SAFA Framework

The sub-humid native rainforest in Yucatan is one of the most endangered in Mexico. Cattle production is one of the main causes of land use change and silvopastoral systems are a feasible alternative. This work compares the sustainable performance of silvopastoral (native and intensive) and monoculture cattle farms in the state of Yucatan using the Sustainability Assessment for Food and Agriculture (SAFA) framework. Questionnaires and semi-structured interviews were applied in 9 farms. Responses were fed to the SAFA Tool to obtain sustainability polygons. Percentages of SAFA themes positively and negatively valuated were calculated. Native farms had positive ratings for Participation, Land, Biodiversity and Cultural Diversity, whereas intensive excelled on Holistic Management. Native farms had limited ratings for Decent Livelihood. Native farms (and one intensive silvopastoral farm) had the highest percentages of themes positively valuated compared to monocultures (and one intensive silvopastoral farm), which scored the lowest. Positive evaluations identified native systems as an option for sustainable production; however, areas of opportunity in all farms were discovered. This is the first comparative study using SAFA to evaluate differences in farming systems in the Mexican tropics, providing valuable information to generate policies and incentives on sustainable livestock production, as well as for improving evaluation tools for local application