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1.
Vet Q ; 43(1): 1-10, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36594266

RESUMO

BACKGROUND: The COVID-19 pandemic, caused by SARS-CoV-2 infection, has become the most devastating zoonotic event in recent times, with negative impacts on both human and animal welfare as well as on the global economy. Although SARS-CoV-2 is considered a human virus, it likely emerged from animals, and it can infect both domestic and wild animals. This constitutes a risk for human and animal health including wildlife with evidence of SARS-CoV-2 horizontal transmission back and forth between humans and wild animals. AIM: Molecular surveillance in different wildlife rehabilitation centers and wildlife associated institutions in Chile, which are critical points of animal-human interaction and wildlife conservation, especially since the aim of wildlife rehabilitation centers is to reintroduce animals to their original habitat. MATERIALS AND METHODS: The survey was conducted in six WRCs and three wildlife associated institutions. A total of 185 samples were obtained from 83 individuals belonging to 15 different species, including vulnerable and endangered species. Each specimen was sampled with two different swabs: one oropharyngeal or nasopharyngeal according to the nostril diameter, and/or a second rectal sample. RNA was extracted from the samples and two different molecular assays were performed: first, a conventional RT-PCR with pan-coronavirus primers and a second SARS-CoV-2 qPCR targeting the N and S genes. RESULTS: All 185 samples were negative for SARS-CoV-2. CLINICAL RELEVANCE: This study constitutes the first report on the surveillance of SARS-CoV-2 from wildlife treated in rehabilitation centers in Chile, and supports the biosafety procedures adopted in those centers.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Animais , SARS-CoV-2/genética , COVID-19/epidemiologia , COVID-19/veterinária , Animais Selvagens , Pandemias , Teste para COVID-19/veterinária
2.
Animals (Basel) ; 12(2)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35049765

RESUMO

Two main challenges when controlling alien American mink (Neovison vison) in Patagonia are to maximize campaign efficacy and cost-effectiveness and to avoid trapping native species. We designed and tested new variants of collapsible wire box traps, compared the efficacy of a food-based bait and a scent lure and compared catch rates in different seasons of the year. We used the data to model the efficiency rate of the trapping and to determine the trapping effort required to remove 70-90% of the estimated discrete mink population. Between January 2018 and March 2021, we operated 59 trapping transects over 103 three-day trapping periods in southern Chile. Traps were first baited with canned fish, and afterwards with mink anal gland lure. We compared the efficacy of mink capture with that of our previous study. We trapped 196 mink (125 males, 71 females), with most captures in summer. The medium-sized GMV-18 trap caught more male mink, but the more compact GMV-13 caught fewer non-target rodents and no native mammals. The scent lure was more successful than the canned fish when the previous campaign's data were included in the analysis. There was also a significant improvement in the proportion of female mink trapped and reduced labour compared with our previous campaign that used larger traps, fish bait and 400-500 m trap spacings. We caught relatively more females than males after the third night of trapping on a transect. Our data analysis supports the use of the GMV-13 variant of wire cage trap as the best trap size: it is effective on female mink, small, cheap and easy to transport. Combined with mink anal scent lure, it reduces the possibility of trapping native species compared with other traps tested in Chile. As the most efficient method for removing at least 70% of the estimated discrete mink population within the area covered by each trap transect in southern Chile tested to date, we recommend trapping campaigns using GMV-13 during summer, with a 200-m trap spacing, for up to 6 days before moving traps to a new site, with a combination of three days with a female scent gland lure, followed by three days with a male scent gland lure.

3.
J Appl Anim Welf Sci ; 25(4): 311-325, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32985259

RESUMO

Free-ranging dogs (FRDs), are a problem in several countries, with impacts on humans, domestic animals, and wildlife, although increasing evidence suggests that most FRDs are owned. Therefore, understanding dog ownership on a fine scale is critical. The main objectives of this study were to explore dog management in rural localities from central Chile focusing on modeling owner-related variables associated with dog confinement and characterize confined and FRDs populations. Interviews (170) were carried out in Paine municipality, reporting a human:dog ratio of 1.5:1, and dogs in most households (85.9%, 146/170). Thirty-seven percent (54/146) of those households did not confine their dog(s) to some degree, and 41% (196/472) of surveyed dogs were FRD. Based on multivariable logistic regression models, non-confinement was decreased by (i) negative opinion of owners toward roaming behavior of their dogs, (ii) negative opinion toward FRDs, among others. Dog confinement increased along with owners' concerns about the impacts of their dogs on others. Owned-FRDs tended to have poorer general care than confined dogs. Our findings represent a contribution to the understanding of the human dimensions behind FRDs and provide critical quantitative elements to consider when planning effective control strategies.


Assuntos
Bem-Estar do Animal , Cães , Propriedade , Animais , Animais Domésticos , Animais Selvagens , Chile , Humanos , População Rural
4.
Transbound Emerg Dis ; 68(4): 2094-2110, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32985137

RESUMO

The aim of this study was to perform a molecular survey and characterize Bartonella spp. and haemotropic Mycoplasma (haemoplasmas) in invasive American minks (Neovison vison) from Southern Chile. Additionally, we addressed risk factors for positivity in both groups of agents. Blood and/or tissue samples from 246 minks were analysed by qPCR targeting the nuoG gene for Bartonella spp. and conventional (c)PCR for 16S rRNA for haemotropic Mycoplasma spp. nuoG qPCR-positive Bartonella spp. samples were submitted to cPCR assays (ITS, ribC, gltA, rpoB, pap-31 and ftsZ genes) to perform phylogenetic inferences. Haemotropic Mycoplasma spp. 16S-positive samples were further amplified by cPCR targeting RNaseP gene (160-210 bp) and by two overlapping 16S rRNA cPCR assays to amplify a larger portion of the gene (1,200bp) for phylogenetics. Bartonella DNA was detected in 8.9% of minks (22/246). Out of 22 nuoG qPCR-positive samples, one and two showed positive results in cPCR assays based on ITS and ribC, respectively. Consistent sequencing results were obtained for only one ITS sample (464 bp sequence), which shared 99.6% identity with B. clarridgeiae. Two per cent of minks (5/246) were positive for 16S rRNA haemotropic Mycoplasma-cPCR assay. Two concatenated sequences of 16S rRNA (1,176 and 1,230 bp) were obtained: one sample shared 97.87% identity with haemotropic Mycoplasma sp. from a wild rodent, and the other 96.49% identity with 'Candidatus Mycoplasma haematoparvum' from a dog. All BLAST results were supported by phylogenetic analysis. One haemoplasma RNase P sequence shared 94.86% identity with Mycoplasma haemofelis from a cat. No risk factors for PCR positivity were identified. In a nutshell, Bartonella clarridgeiae and a potentially novel haemoplasma closely related to haemoplasmas previously reported in rodents, dogs, domestic and wild cats were described for the first time in American minks.


Assuntos
Bartonella , Vison , Infecções por Mycoplasma , Animais , Bartonella/genética , Doenças do Gato , Gatos , DNA Bacteriano/genética , Doenças do Cão , Cães , Mycoplasma , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/veterinária , Filogenia , RNA Ribossômico 16S/genética
5.
Trop Anim Health Prod ; 53(1): 2, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33196883

RESUMO

Leptospirosis is a zoonosis of global distribution, caused by the infection of pathogenic Leptospira, a group of bacteria capable of infecting both domestic and wild animals. Mink (Neovison vison) in southern Chile is recognized as a wild and synanthropic rodent predator (among various other prey), and Leptospira infection in them can be acquired through contact with the pathogen in the environment or by eating infected prey. Thus, the aim of this study was to provide more specifics regarding the source of the infection for the American mink under the conditions of Southern Chile. Minks were captured in the Los Ríos region, southern Chile, in an area with well-developed dairy farming. Two areas were selected for mink trapping, one with a high degree of dairy farming and a second with a low degree of dairy farming. Within them, 16 study sites were visited, and 45 American mink were trapped and euthanized to obtain kidney tissue and blood serum samples for bacteria isolation and determination of antibodies titers, respectively. Molecular characterization of the isolated strains was performed. Three minks from sites of high-dairy farming industry and only one from sites with low-degree dairy farming were detected as infected through molecular confirmation. This study shows evidence that confirms previous findings made in southern Chile, regarding mink as host of Leptospira interrogans serovar Hardjo-prajitno associated to cattle-farming areas. However, typing information ( Leptospira interrogans Copenhageni and Icterohaemorrhagiae ) suggests that the consumption of rodents may also be a potential source of infection.


Assuntos
Leptospira interrogans/isolamento & purificação , Leptospirose/veterinária , Vison , Animais , Bovinos , Chile , Indústria de Laticínios , Feminino , Leptospirose/microbiologia , Masculino , Zoonoses/microbiologia
6.
J Wildl Dis ; 56(4): 962-964, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32609602

RESUMO

Toxoplasma gondii is a worldwide-distributed protozoon that infects warm-blooded animals. We determined T. gondii exposure in one marine otter (Lontra felina) and four domestic cats (Felis catus) along the northern and central coast of Chile, indicating a low seroprevalence of 5% (1/19) and 8% (4/50) respectively, likely related to arid environment.


Assuntos
Doenças do Gato/parasitologia , Lontras/parasitologia , Toxoplasma/imunologia , Toxoplasmose Animal/parasitologia , Animais , Gatos , Chile/epidemiologia , Toxoplasmose Animal/epidemiologia
7.
PLoS One ; 13(11): e0206502, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30412585

RESUMO

A lack of knowledge of naturally occurring pathogens is limiting our ability to use the Antarctic to study the impact human-mediated introduction of infectious microorganisms have on this relatively uncontaminated environment. As no large-scale coordinated effort to remedy this lack of knowledge has taken place, we rely on smaller targeted efforts to both study present microorganisms and monitor the environment for introductions. In one such effort, we isolated Campylobacter species from fecal samples collected from wild birds in the Antarctic Peninsula and the sub-Antarctic island of South Georgia. Indeed, in South Georgia, we found Campylobacter lari and the closely related Campylobacter peloridis, but also distantly related human-associated multilocus sequence types of Campylobacter jejuni. In contrast, in the Antarctic Peninsula, we found C. lari and two closely related species, Campylobacter subantarcticus and Campylobacter volucris, but no signs of human introduction. In fact, our finding of human-associated sequence types of C. jejuni in South Georgia, but not in the Antarctic Peninsula, suggests that efforts to limit the spread of infectious microorganisms to the Antarctic have so far been successful in preventing the introduction of C. jejuni. However, we do not know how it came to South Georgia and whether the same mode of introduction could spread it from there to the Antarctic Peninsula.


Assuntos
Aves/microbiologia , Campylobacter/isolamento & purificação , Animais , Regiões Antárticas , Campylobacter/classificação , Campylobacter/genética , Frequência do Gene
8.
PLoS One ; 13(6): e0199085, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29924844

RESUMO

The increase in human population and domestic pets, such as cats, are generating important consequences in terms of habitat loss and pathogen pollution of coastal ecosystems with potential to generate negative impacts in marine biodiversity. Toxoplasma gondii is the etiological agent of zoonotic disease toxoplasmosis, and is associated with cat abundance and anthropogenic disturbance. The presence of T. gondii oocysts in the ocean has negatively affected the health status of the threatened Southern sea otter (Enhydra lutris nereis) populations. The present study analyzed seroprevalence and presence of T. gondii DNA in American mink (Neovison vison), Southern river otters (Lontra provocax) and domestic cats (Felis silvestris catus) in four different areas in Southern Chile comprising studies in rivers and lakes in Andean foothills and mountains, marine habitat and island coastal ecosystems. Mean seroprevalence of T. gondii in the study was 64% of 151 total animals sampled: 59% of 73 American mink, 77% of 13 Southern river otters, 68% of 65 domestic cats and in two of two kodkods (Leopardus guigna). Toxoplasma gondii DNA was detected in tissues from one American mink and one Southern river otter. The present study confirms the widespread distribution of T. gondii in Southern Chile, and shows a high exposure of semiaquatic mustelids and domestic cats to the parasite. Cats and anthropogenic disturbance have a role in the maintenance of T. gondii infection in ecosystems of southern Chile.


Assuntos
Animais Selvagens/parasitologia , Doenças do Gato/epidemiologia , Gatos/parasitologia , Ecossistema , Vison/parasitologia , Lontras/parasitologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/epidemiologia , Animais , Animais Domésticos/parasitologia , Doenças do Gato/parasitologia , Chile/epidemiologia , Espécies em Perigo de Extinção , Felidae/parasitologia , Água Doce/parasitologia , Atividades Humanas , Saúde da População Rural , Estudos Soroepidemiológicos , Toxoplasmose Animal/transmissão , Saúde da População Urbana
9.
J Med Entomol ; 53(6): 1433-1443, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27539151

RESUMO

Fleas and ticks are parasites of wild and domestic mammals, and can be vectors of several pathogens. In rural areas, domestic carnivores such as the domestic dog (Canis lupus familiaris L.), may act as a "bridge" between natural areas and human settlements where ectoparasites can be used as a metric of such link. The aim of this study was to identify fleas, ticks, and Rickettsia spp., collected from domestic and wild carnivores in a natural reserve and surrounding human settlements in Central Chile, using morphological keys and molecular analysis. We surveyed 170 households from which 107 dogs and eight cats were sampled. From the natural reserve, we sampled two chilla foxes (Pseudalopex griseus Gray), two lesser grison (Galictis cuja Molina), three kodkods (Leopardus guigna Molina), and four dogs. From dogs, we collected Ctenocephalides felis Bouché, Ctenocephalides canis Curtis, Pulex irritans L., and Rhipicephalus sanguineus s.l. Latreille; C. felis was the most frequent ectoparasite. Cats were infested only by C. felis and Rh. sanguineus s.l. From wild carnivores, we obtained C. canis and P. irritans, the latter being most frequent. Molecular analysis of P. irritans detected 10 haplotypes and two main clades, which tended to separate fleas from wild and domestic hosts. Molecular analysis of ompA and ompB genes confirmed the presence of Rickettsia felis in fleas collected from owned dogs and cats, which could represent a potential risk factor of R. felis transmission in the area.


Assuntos
Carnívoros , Doenças do Gato/epidemiologia , Doenças do Cão/epidemiologia , Infestações por Pulgas/veterinária , Sifonápteros/fisiologia , Infestações por Carrapato/veterinária , Carrapatos/fisiologia , Animais , Proteínas de Bactérias/genética , Doenças do Gato/microbiologia , Doenças do Gato/parasitologia , Gatos , Chile/epidemiologia , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Infestações por Pulgas/epidemiologia , Infestações por Pulgas/parasitologia , Proteínas de Insetos/genética , Filogenia , Prevalência , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/microbiologia , Infecções por Rickettsia/veterinária , Rickettsia felis/classificação , Rickettsia felis/genética , Rickettsia felis/isolamento & purificação , Fatores de Risco , Análise de Sequência de DNA/veterinária , Sifonápteros/classificação , Sifonápteros/genética , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Carrapatos/classificação , Carrapatos/genética
10.
Vet Res ; 46: 92, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26338730

RESUMO

Rabies remains a disease of significant public health concern. In the Americas, bats are an important source of rabies for pets, livestock, and humans. For effective rabies control and prevention, identifying potential areas for disease occurrence is critical to guide future research, inform public health policies, and design interventions. To anticipate zoonotic infectious diseases distribution at coarse scale, veterinary epidemiology needs to advance via exploring current geographic ecology tools and data using a biological approach. We analyzed bat-borne rabies reports in Chile from 2002 to 2012 to establish associations between rabies occurrence and environmental factors to generate an ecological niche model (ENM). The main rabies reservoir in Chile is the bat species Tadarida brasiliensis; we mapped 726 occurrences of rabies virus variant AgV4 in this bat species and integrated them with contemporary Normalized Difference Vegetation Index (NDVI) data from the Moderate Resolution Imaging Spectroradiometer (MODIS). The correct prediction of areas with rabies in bats and the reliable anticipation of human rabies in our study illustrate the usefulness of ENM for mapping rabies and other zoonotic pathogens. Additionally, we highlight critical issues with selection of environmental variables, methods for model validation, and consideration of sampling bias. Indeed, models with weak or incorrect validation approaches should be interpreted with caution. In conclusion, ecological niche modeling applications for mapping disease risk at coarse geographic scales have a promising future, especially with refinement and enrichment of models with additional information, such as night-time light data, which increased substantially the model's ability to anticipate human rabies.


Assuntos
Quirópteros/virologia , Meio Ambiente , Saúde Pública/métodos , Raiva/epidemiologia , Imagens de Satélites , Animais , Chile/epidemiologia , Métodos Epidemiológicos/veterinária , Geografia , Modelos Teóricos , Raiva/virologia , Medição de Risco , Fatores de Tempo
11.
Rev Chilena Infectol ; 32(3): 289-93, 2015 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-26230435

RESUMO

INTRODUCTION: Rabies is a lethal but preventable disease. Knowing the extent of immunization coverage among at risk populations, may help to guide immunization efforts, as well as increase the effectiveness of rabies control and prevention programs. AIM: To determine the proportion of wildlife veterinarians in Chile, as part of a group at risk of rabies transmission. METHODS: An electronic survey was sent to wildlife veterinarians in Chile. RESULTS: We found that veterinarians in Chile work mainly with carnivores and deer compared to other mammals (p < 0.001), rarely works with bats (p = 0.6572). Most of the participants had been bitten by domestic animals, while a lesser proportion (29%) by wild animals. Most of the participants never received rabies vaccination (53%), while within the group that had started a rabies vaccination scheme, a substantial proportion (39%) did not complete it. DISCUSSION AND CONCLUSION: Identify the vaccination status of risk groups is important for infectious disease control and prevention programs, as this information helps to identify priority groups during outbreaks or vaccine scarcity. Wildlife veterinarians in Chile are at risk of rabies transmission and should be included in rabies prevention programs, especially considering their vulnerability and lack of biosafety practices. Increasing education in rabies epidemiology and prevention is urgently needed in veterinary faculties in Chile.


Assuntos
Doenças Profissionais/prevenção & controle , Vacina Antirrábica/administração & dosagem , Raiva/prevenção & controle , Vacinação/estatística & dados numéricos , Médicos Veterinários/estatística & dados numéricos , Adulto , Animais , Animais Selvagens , Chile , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População
12.
Rev. chil. infectol ; 32(3): 289-293, jun. 2015. graf, tab
Artigo em Espanhol | LILACS | ID: lil-753486

RESUMO

Introduction: Rabies is a lethal but preventable disease. Knowing the extent of immunization coverage among at risk populations, may help to guide immunization efforts, as well as increase the effectiveness of rabies control and prevention programs. Aim: To determine the proportion of wildlife veterinarians in Chile, as part of a group at risk of rabies transmission. Methods: An electronic survey was sent to wildlife veterinarians in Chile. Results: We found that veterinarians in Chile work mainly with carnivores and deer compared to other mammals (p < 0.001), rarely works with bats (p = 0.6572). Most of the participants had been bitten by domestic animals, while a lesser proportion (29%) by wild animals. Most of the participants never received rabies vaccination (53%), while within the group that had started a rabies vaccination scheme, a substantial proportion (39%) did not complete it. Discussion and conclusion: Identify the vaccination status of risk groups is important for infectious disease control and prevention programs, as this information helps to identify priority groups during outbreaks or vaccine scarcity. Wildlife veterinarians in Chile are at risk of rabies transmission and should be included in rabies prevention programs, especially considering their vulnerability and lack of biosafety practices. Increasing education in rabies epidemiology and prevention is urgently needed in veterinary faculties in Chile.


Introducción: La rabia es una enfermedad infecciosa mortal pero prevenible. Establecer si existe una adecuada inmunización pre-exposición contra la rabia en un grupo de riesgo, puede ayudar a enfocar los esfuerzos de inmunización para hacer efectivos los programas de control y prevención de la enfermedad. Objetivo: Determinar mediante una encuesta la proporción de veterinarios de fauna silvestre como grupo de riesgo que han recibido inmunización contra la rabia. Métodos: Se realizó una encuesta electrónica a veterinarios de fauna de vida silvestre de Chile. Resultados: Los veterinarios encuestados tienden a trabajar con carnívoros y ciervos en comparación con otros mamíferos (p < 0,001), rara vez con murciélagos (p = 0,6572). La mayoría de los encuestados había sido mordido por animales domésticos y una proporción menor (29%) por animales silvestres. La mayoría nunca había sido vacunado contra la rabia (53%), mientras que del grupo que sí había recibido vacunación anti-rábica, una importante proporción (39%) no completó el esquema de vacunación. Sorprendentemente, este grupo de profesionales rara vez trabaja con murciélagos (p = 0,6572), lo que puede reducir su exposición a linajes de rabia transmitida por murciélagos. Discusión y Conclusión: Identificar el estado de inmunización contra la rabia en grupos de riesgo es una información importante para evaluar los programas de prevención y control de enfermedades infecciosas y podría ayudar a identificar grupos prioritarios en situaciones de brote o escasez de vacuna. Los veterinarios de fauna de vida silvestre en Chile constituyen un grupo vulnerable: no mantienen prácticas de bioseguridad necesarias y tienen riesgo de adquirir la encefalitis rábica por lo que deberían ser considerados en los programas de prevención pre-exposición de la enfermedad. La educación sobre la epidemiología y prevención de la rabia es urgente en las facultades de medicina veterinaria en Chile.


Assuntos
Adulto , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/prevenção & controle , Vacina Antirrábica/administração & dosagem , Raiva/prevenção & controle , Vacinação/estatística & dados numéricos , Médicos Veterinários/estatística & dados numéricos , Animais Selvagens , Chile , Vigilância da População
14.
Rev Inst Med Trop Sao Paulo ; 57(1): 63-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25651328

RESUMO

The situation of rabies in America is complex: rabies in dogs has decreased dramatically, but bats are increasingly recognized as natural reservoirs of other rabies variants. Here, bat species known to be rabies-positive with different antigenic variants, are summarized in relation to bat conservation status across Latin America. Rabies virus is widespread in Latin American bat species, 22.5%75 of bat species have been confirmed as rabies-positive. Most bat species found rabies positive are classified by the International Union for Conservation of Nature as "Least Concern". According to diet type, insectivorous bats had the most species known as rabies reservoirs, while in proportion hematophagous bats were the most important. Research at coarse spatial scales must strive to understand rabies ecology; basic information on distribution and population dynamics of many Latin American and Caribbean bat species is needed; and detailed information on effects of landscape change in driving bat-borne rabies outbreaks remains unassessed. Finally, integrated approaches including public health, ecology, and conservation biology are needed to understand and prevent emergent diseases in bats.


Assuntos
Quirópteros/classificação , Quirópteros/virologia , Vírus da Raiva/isolamento & purificação , América , Animais , Biodiversidade
15.
Rev. Inst. Med. Trop. Säo Paulo ; 57(1): 63-72, Jan-Feb/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-736363

RESUMO

The situation of rabies in America is complex: rabies in dogs has decreased dramatically, but bats are increasingly recognized as natural reservoirs of other rabies variants. Here, bat species known to be rabies-positive with different antigenic variants, are summarized in relation to bat conservation status across Latin America. Rabies virus is widespread in Latin American bat species, 22.5%75 of bat species have been confirmed as rabies-positive. Most bat species found rabies positive are classified by the International Union for Conservation of Nature as “Least Concern”. According to diet type, insectivorous bats had the most species known as rabies reservoirs, while in proportion hematophagous bats were the most important. Research at coarse spatial scales must strive to understand rabies ecology; basic information on distribution and population dynamics of many Latin American and Caribbean bat species is needed; and detailed information on effects of landscape change in driving bat-borne rabies outbreaks remains unassessed. Finally, integrated approaches including public health, ecology, and conservation biology are needed to understand and prevent emergent diseases in bats.


La situación de rabia en América es compleja: la rabia en perros ha disminuido drásticamente pero los murciélagos están siendo reconocidos cada vez más como reservorios naturales de otras variantes de rabia. Aquí compilamos las especies de murciélagos reconocidas como positivas a rabia con diferentes variantes antigénicas, así como su relación con el estado de conservación de los murciélagos a lo largo de América Latina. El virus de rabia está ampliamente distribuido en las especies de murciélagos de América Latina, 22.5% (75) de las especies de murciélagos conocidas han sido confirmadas como especies positivas a rabia. La mayoría de las especies de murciélagos reportadas como positivas a rabia son clasificadas por la Unión Internacional para la Conservación de la Naturaleza como “Preocupación Menor”. De acuerdo al tipo de dieta, los murciélagos insectívoros tuvieron la mayor cantidad de especies reconocidas como reservorio del virus rabia, mientras en proporción los hematófagos fueron los más importantes. Investigaciones a escala gruesa deben buscar entender aspectos de ecología de la rabia; es necesaria la información básica sobre la distribución y dinámica poblacional para muchas especies de murciélagos de América Latina y el Caribe; y el efecto del cambio del paisaje en la generación de brotes de rabia transmitida por murciélagos permanece sin ser evaluado. Por último, para entender y prevenir enfermedades emergentes a partir de los murciélagos es necesario un enfoque integral incluyendo salud pública, ecología y biología de la conservación.


Assuntos
Animais , Quirópteros/classificação , Quirópteros/virologia , Vírus da Raiva/isolamento & purificação , América , Biodiversidade
16.
Geospat Health ; 9(1): 221-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25545939

RESUMO

Emerging infectious diseases can present serious threats to wildlife, even to the point of causing extinction. Whitenose fungus (Pseudogymnoascus destructans) is causing an epizootic in bats that is expanding rapidly, both geographically and taxonomically. Little is known of the ecology and distributional potential of this intercontinental pathogen. We address this gap via ecological niche models that characterise coarse resolution niche differences between fungus populations on different continents, identifying areas potentially vulnerable to infection in South America. Here we explore a novel approach to identifying areas of potential distribution across novel geographic regions that avoids perilious extrapolation into novel environments. European and North American fungus populations show differential use of environmental space, but rather than niche differentiation, we find that changes are best attributed to climatic differences between the two continents. Suitable areas for spread of the pathogen were identified across southern South America; however caution should be taken to avoid underestimating the potential for spread of this pathogen in South America.


Assuntos
Ascomicetos , Quirópteros/microbiologia , Micoses/veterinária , América/epidemiologia , Animais , Ascomicetos/fisiologia , Clima , Ecologia , Modelos Estatísticos , Micoses/epidemiologia , Micoses/transmissão , Análise Espacial
17.
mBio ; 5(3): e01098-14, 2014 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-24803521

RESUMO

ABSTRACT Distinct lineages of avian influenza viruses (AIVs) are harbored by spatially segregated birds, yet significant surveillance gaps exist around the globe. Virtually nothing is known from the Antarctic. Using virus culture, molecular analysis, full genome sequencing, and serology of samples from Adélie penguins in Antarctica, we confirmed infection by H11N2 subtype AIVs. Their genetic segments were distinct from all known contemporary influenza viruses, including South American AIVs, suggesting spatial separation from other lineages. Only in the matrix and polymerase acidic gene phylogenies did the Antarctic sequences form a sister relationship to South American AIVs, whereas distant phylogenetic relationships were evident in all other gene segments. Interestingly, their neuraminidase genes formed a distant relationship to all avian and human influenza lineages, and the polymerase basic 1 and polymerase acidic formed a sister relationship to the equine H3N8 influenza virus lineage that emerged during 1963 and whose avian origins were previously unknown. We also estimated that each gene segment had diverged for 49 to 80 years from its most closely related sequences, highlighting a significant gap in our AIV knowledge in the region. We also show that the receptor binding properties of the H11N2 viruses are predominantly avian and that they were unable to replicate efficiently in experimentally inoculated ferrets, suggesting their continuous evolution in avian hosts. These findings add substantially to our understanding of both the ecology and the intra- and intercontinental movement of Antarctic AIVs and highlight the potential risk of an incursion of highly pathogenic AIVs into this fragile environment. IMPORTANCE Avian influenza viruses (AIVs) are typically maintained and spread by migratory birds, resulting in the existence of distinctly different viruses around the world. However, AIVs have not previously been detected in Antarctica. In this study, we characterized H11N2 viruses sampled from Adélie penguins from two geographically different sites in Antarctica and show that the segmented AIV genome diverged between 49 and 80 years ago from other AIVs, with several genes showing similarity and shared ancestry with H3N8 equine influenza viruses. This study provides the first insight into the ecology of AIVs in Antarctica and highlights the potential risk of an introduction of highly pathogenic AIVs into the continent.


Assuntos
Evolução Molecular , Vírus da Influenza A/genética , Influenza Aviária/virologia , Animais , Regiões Antárticas , Anticorpos Antivirais/sangue , Genes Virais , Genótipo , Geografia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Especificidade de Hospedeiro , Vírus da Influenza A/classificação , Influenza Aviária/epidemiologia , Modelos Moleculares , Filogenia , Conformação Proteica , Estudos Soroepidemiológicos , Spheniscidae/virologia
18.
PLoS Negl Trop Dis ; 7(12): e2577, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24349592

RESUMO

Rabies was known to humans as a disease thousands of years ago. In America, insectivorous bats are natural reservoirs of rabies virus. The bat species Tadarida brasiliensis and Lasiurus cinereus, with their respective, host-specific rabies virus variants AgV4 and AgV6, are the principal rabies reservoirs in Chile. However, little is known about the roles of bat species in the ecology and geographic distribution of the virus. This contribution aims to address a series of questions regarding the ecology of rabies transmission in Chile. Analyzing records from 1985-2011 at the Instituto de Salud Pública de Chile (ISP) and using ecological niche modeling, we address these questions to help in understanding rabies-bat ecological dynamics in South America. We found ecological niche identity between both hosts and both viral variants, indicating that niches of all actors in the system are undifferentiated, although the viruses do not necessarily occupy the full geographic distributions of their hosts. Bat species and rabies viruses share similar niches, and our models had significant predictive power even across unsampled regions; results thus suggest that outbreaks may occur under consistent, stable, and predictable circumstances.


Assuntos
Quirópteros/virologia , Filogeografia , Vírus da Raiva/classificação , Vírus da Raiva/genética , Raiva/transmissão , Topografia Médica , Zoonoses/transmissão , Animais , Chile/epidemiologia , Ecologia , Humanos , Raiva/virologia , Vírus da Raiva/isolamento & purificação , América do Sul , Zoonoses/virologia
19.
BMC Evol Biol ; 11: 53, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21356052

RESUMO

BACKGROUND: A number of studies have described the extension of ice cover in western Patagonia during the Last Glacial Maximum, providing evidence of a complete cover of terrestrial habitat from 41°S to 56°S and two main refugia, one in south-eastern Tierra del Fuego and the other north of the Chiloé Island. However, recent evidence of high genetic diversity in Patagonian river species suggests the existence of aquatic refugia in this region. Here, we further test this hypothesis based on phylogeographic inferences from a semi-aquatic species that is a top predator of river and marine fauna, the huillín or Southern river otter (Lontra provocax). RESULTS: We examined mtDNA sequences of the control region, ND5 and Cytochrome-b (2151 bp in total) in 75 samples of L. provocax from 21 locations in river and marine habitats. Phylogenetic analysis illustrates two main divergent clades for L. provocax in continental freshwater habitat. A highly diverse clade was represented by haplotypes from the marine habitat of the Southern Fjords and Channels (SFC) region (43°38' to 53°08'S), whereas only one of these haplotypes was paraphyletic and associated with northern river haplotypes. CONCLUSIONS: Our data support the hypothesis of the persistence of L. provocax in western Patagonia, south of the ice sheet limit, during last glacial maximum (41°S latitude). This limit also corresponds to a strong environmental change, which might have spurred L. provocax differentiation between the two environments.


Assuntos
Ecossistema , Genética Populacional , Lontras/genética , Filogeografia , Adaptação Biológica/genética , Animais , Argentina , Chile , DNA Mitocondrial/genética , Haplótipos , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
20.
J Hered ; 101(6): 676-89, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20688888

RESUMO

The evolutionary history of a species can be revealed by phylogeographical analysis; nevertheless, not only historical but also contemporary processes can imprint on the distribution of genetic diversity. We report on the phylogeny of Lontra ssp. in South America, and the role of spatial heterogeneity in shaping the distribution and population structure of the endangered marine otter, Lontra felina. Analyzing a total of 2261 bp of mitochondrial DNA (mtDNA) revealed the recent divergence of L. felina from L. provocax. A strong population structure (Φ(st) = 0.83, P < 0.0001) and a significant pattern of isolation by distance were described for L. felina (n = 168) across a wide geographical distribution (13°53'S to 43°36'S). Lontra felina mtDNA phylogeny is composed of 2 main clades: a clade from Peru and another composed of Chilean haplotypes. Northern populations show different divergent lineages and higher genetic diversity when compared with more recently colonized southern populations. Furthermore, long sandy beaches seem to act as barriers to dispersal, creating 2 evolutionary significant units in agreement with subspecies previous description, and at least 5 different management units (MUs). At a fine spatial scale, the size of rocky seashore patches, the distance between patches and anthropogenic factors also play important roles in species gene flow.


Assuntos
Citocromos b/genética , DNA Mitocondrial/genética , Variação Genética , NADH Desidrogenase/genética , Lontras/genética , Animais , Sequência de Bases , Chile , Mudança Climática , Barreiras de Comunicação , Fluxo Gênico , Deriva Genética , Genética Populacional , Geografia , Haplótipos , Dados de Sequência Molecular , Peru , Filogenia , Filogeografia , Reação em Cadeia da Polimerase , Dinâmica Populacional , Análise de Sequência de DNA
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