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2.
J Biomed Semantics ; 15(1): 2, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38650032

ABSTRACT

The more science advances, the more questions are asked. This compounding growth can make it difficult to keep up with current research directions. Furthermore, this difficulty is exacerbated for junior researchers who enter fields with already large bases of potentially fruitful research avenues. In this paper, we propose a novel task and a recommender system for research directions, RecSOI, that draws from statements of ignorance (SOIs) found in the research literature. By building researchers' profiles based on textual elements, RecSOI generates personalized recommendations of potential research directions tailored to their interests. In addition, RecSOI provides context for the recommended SOIs, so that users can quickly evaluate how relevant the research direction is for them. In this paper, we provide an overview of RecSOI's functioning, implementation, and evaluation, demonstrating its effectiveness in guiding researchers through the vast landscape of potential research directions.


Subject(s)
Biomedical Research , Research , Humans
3.
Proc Natl Acad Sci U S A ; 121(14): e2317915121, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38536751

ABSTRACT

The flowing, jamming, and avalanche behavior of granular materials is satisfyingly universal and vexingly hard to tune: A granular flow is typically intermittent and will irremediably jam if too confined. Here, we show that granular metamaterials made from particles with a negative Poisson's ratio yield more easily and flow more smoothly than ordinary granular materials. We first create a collection of auxetic grains based on a re-entrant mechanism and show that each grain exhibits a negative Poisson's ratio regardless of the direction of compression. Interestingly, we find that the elastic and yielding properties are governed by the high compressibility of granular metamaterials: At a given confinement, they exhibit lower shear modulus, lower yield stress, and more frequent, smaller avalanches than materials made from ordinary grains. We further demonstrate that granular metamaterials promote flow in more complex confined geometries, such as intruder and hopper geometries, even when the packing contains only a fraction of auxetic grains. Moreover, auxetic granular metamaterials exhibit enhanced impact absorption. Our findings blur the boundary between complex fluids and metamaterials and could help in scenarios that involve process, transport, and reconfiguration of granular materials.

4.
Sci Total Environ ; 916: 170340, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38278249

ABSTRACT

Although considered one of the most pristine ecosystems, Antarctica has been largely influenced by human activities during the last 50 years, affecting its unique biodiversity. One of the major global threats to health is the emergence of antibiotic-resistant bacteria that may be actively transferred to wildlife. We cultured and tested for antibiotic resistance in 137 cloacal and fresh fecal samples of several avian and marine mammal species from the Antarctic Peninsula, the most impacted area in Antarctica. Alarmingly, 80 % of the isolates showed antibiotic resistance, either phenotypically or genotypically. Most of the resistant bacteria, such as Enterobacteriaceae and Enterococcus species, are part of local gastrointestinal microbiota. Penguins and pinnipeds harbored a great diversity of antibiotic resistance and must be eligible as sentinels for future studies. These results show that antibiotic resistance has rapidly transferred to bacteria in Antarctic wildlife, which is a global matter of concern.


Subject(s)
Caniformia , Spheniscidae , Animals , Humans , Animals, Wild , Ecosystem , Antarctic Regions , Drug Resistance, Microbial , Bacteria
5.
Rev Bras Parasitol Vet ; 32(4): e008223, 2023.
Article in English | MEDLINE | ID: mdl-37909605

ABSTRACT

The tick Amblyomma tigrinum inhabits areas with diverse climatic conditions, with adult stages parasitizing wild canids, such as chilla (Lycalopex griseus) and culpeo (Lycalopex culpaeus) foxes. We described the infestation loads in wild foxes captured at three sites (periurban, rural and wild) through an anthropization gradient in north-central Chile. We tested whether local-scale environmental and/or individual host factors can predict tick abundance by using negative binomial models. During 2018-2020 (spring and summer), we captured 116 foxes (44 chillas and 72 culpeos), and 102 of them were infested with ticks (87.9%, CI=80.6-93.2%). We collected 996 A. tigrinum adult ticks, estimating a total mean abundance of 8.6±0.8 ticks/host. Periurban and rural foxes harbored greater tick loads than foxes from the wild site (2.34 and 1.71 greater, respectively) while tick abundance in summer decreased by up to 57% compared to spring. Tempered, more humid climate conditions of the periurban site could favor the development and survival of adults A. tigrinum; and ticks may have adopted a quiescent stage or similar survival mechanisms to cope with summer temperature increases related to the ongoing megadrought. Further studies are warranted to understand the underlying factors determining the life cycle of A. tigrinum at larger spatiotemporal scales.


Subject(s)
Ixodidae , Tick Infestations , Ticks , Animals , Amblyomma , Foxes/parasitology , Chile , Tick Infestations/epidemiology , Tick Infestations/veterinary , Tick Infestations/parasitology
6.
Arch Public Health ; 81(1): 89, 2023 May 11.
Article in English | MEDLINE | ID: mdl-37170153

ABSTRACT

Health inequalities within and between Member States of the European Union are widely recognized as a public health problem as they determine a significant share of potentially avoidable mortality and morbidity. After years of growing awareness and increasing action taken, a large gap still exists across Europe in terms of policy responses and governance. With the aim to contribute to achieve greater equity in health outcomes, in 2018 a new Joint Action, JAHEE, (Joint Action Health Equity Europe) was funded by the third EU Health Programme, with the main goal of strengthening cooperation between participating countries and of implementing concrete actions to reduce health inequalities. The partnership led by Italy counted 24 countries, conducting actions in five policy domains: monitoring, governance, healthy living environments, health systems and migration, following a three-step implementation approach. Firstly, specific Policy Frameworks for Action (PFA) collecting the available evidence on what practice should be done in each domain were developed. Second, different Country Assessments (CAs) were completed to check the country's adherence to the recommended practice in each domain. The gap between the expected policy response (PFA) and the present policy response (CA) guided the choice of concrete actions to be implemented in JAHEE, many of which are continuing even after the end of JA. Final recommendations based on the best results achieved during JAHEE were elaborated and agreed jointly with the representatives of the involved Ministries of Health. The JAHEE initiative represented an important opportunity for the participating countries to work jointly, and the results show that almost all have increased their level of action and strengthened their capacities to address health inequalities.

7.
Vet Q ; 43(1): 1-10, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36594266

ABSTRACT

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.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Animals , SARS-CoV-2/genetics , COVID-19/epidemiology , COVID-19/veterinary , Animals, Wild , Pandemics , COVID-19 Testing/veterinary
8.
Rev. bras. parasitol. vet ; 32(4): e008223, 2023. tab, graf
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1521814

ABSTRACT

Abstract The tick Amblyomma tigrinum inhabits areas with diverse climatic conditions, with adult stages parasitizing wild canids, such as chilla (Lycalopex griseus) and culpeo (Lycalopex culpaeus) foxes. We described the infestation loads in wild foxes captured at three sites (periurban, rural and wild) through an anthropization gradient in north-central Chile. We tested whether local-scale environmental and/or individual host factors can predict tick abundance by using negative binomial models. During 2018-2020 (spring and summer), we captured 116 foxes (44 chillas and 72 culpeos), and 102 of them were infested with ticks (87.9%, CI=80.6-93.2%). We collected 996 A. tigrinum adult ticks, estimating a total mean abundance of 8.6±0.8 ticks/host. Periurban and rural foxes harbored greater tick loads than foxes from the wild site (2.34 and 1.71 greater, respectively) while tick abundance in summer decreased by up to 57% compared to spring. Tempered, more humid climate conditions of the periurban site could favor the development and survival of adults A. tigrinum; and ticks may have adopted a quiescent stage or similar survival mechanisms to cope with summer temperature increases related to the ongoing megadrought. Further studies are warranted to understand the underlying factors determining the life cycle of A. tigrinum at larger spatiotemporal scales.


Resumo Amblyomma tigrinum habita em áreas com diversas condições climáticas, com estágios adultos, geralmente, parasitando canídeos silvestres, como chilla (Lycalopex griseus) e culpeo (Lycalopex culpaeus). Neste trabalho, são descritas as cargas de infestação de A. tigrinum em raposas silvestres, capturadas em três locais (periurbano, rural e silvestre) no centro-norte do Chile. Foi testado se os fatores ambientais e/ou individuais do hospedeiro, em escala local, podem prever a abundância de carrapatos, usando-se modelos binomiais negativos. Durante 2018-2020 (primavera e verão), foram capturadas 116 raposas (44 chillas e 72 culpeos), e 102 delas estavam infestadas por carrapatos (87,9%, IC=80,6-93,2%). Foram coletados 996 carrapatos adultos de A. tigrinum, estimando-se uma abundância média total de 8,6±0,8 carrapatos/hospedeiro. As raposas periurbanas e rurais abrigaram cargas de carrapatos maiores do que as raposas do local silvestre (2,34 e 1,71 maior, respectivamente), enquanto a abundância de carrapatos, no verão, diminuiu até 57% em comparação com a primavera. As condições climáticas temperadas e mais úmidas do sítio periurbano podem favorecer o desenvolvimento e a sobrevivência dos adultos de A. tigrinum; e os carrapatos podem ter adotado um estágio quiescente ou mecanismos de sobrevivência semelhantes, para lidar com os aumentos de temperatura no verão, relacionados à mega seca em andamento.

9.
PLoS One ; 17(12): e0273994, 2022.
Article in English | MEDLINE | ID: mdl-36508452

ABSTRACT

Peer review is an important part of science, aimed at providing expert and objective assessment of a manuscript. Because of many factors, including time constraints, unique expertise needs, and deference, many journals ask authors to suggest peer reviewers for their own manuscript. Previous researchers have found differing effects about this practice that might be inconclusive due to sample sizes. In this article, we analyze the association between author-suggested reviewers and review invitation, review scores, acceptance rates, and subjective review quality using a large dataset of close to 8K manuscripts from 46K authors and 21K reviewers from the journal PLOS ONE's Neuroscience section. We found that all-author-suggested review panels increase the chances of acceptance by 20 percent points vs all-editor-suggested panels while agreeing to review less often. While PLOS ONE has since ended the practice of asking for suggested reviewers, many others still use them and perhaps should consider the results presented here.


Subject(s)
Neurosciences , Peer Review , Cross-Sectional Studies , Peer Review, Research
10.
Sci Data ; 9(1): 467, 2022 08 02.
Article in English | MEDLINE | ID: mdl-35918351

ABSTRACT

Mentorship in science is crucial for topic choice, career decisions, and the success of mentees and mentors. Typically, researchers who study mentorship use article co-authorship and doctoral dissertation datasets. However, available datasets of this type focus on narrow selections of fields and miss out on early career and non-publication-related interactions. Here, we describe Mentorship, a crowdsourced dataset of 743176 mentorship relationships among 738989 scientists primarily in biosciences that avoids these shortcomings. Our dataset enriches the Academic Family Tree project by adding publication data from the Microsoft Academic Graph and "semantic" representations of research using deep learning content analysis. Because gender and race have become critical dimensions when analyzing mentorship and disparities in science, we also provide estimations of these factors. We perform extensive validations of the profile-publication matching, semantic content, and demographic inferences, which mostly cover neuroscience and biomedical sciences. We anticipate this dataset will spur the study of mentorship in science and deepen our understanding of its role in scientists' career outcomes.


Subject(s)
Biological Science Disciplines , Mentors , Research Personnel , Demography , Humans
11.
Emerg Infect Dis ; 28(6): 1250-1253, 2022 06.
Article in English | MEDLINE | ID: mdl-35608824

ABSTRACT

We assessed 4 lizard species in Chile for Trypanosoma cruzi, the causative agent of Chagas disease, and 1 species for its ability to transmit the protozoan to uninfected kissing bugs. All lizard species were infected, and the tested species was capable of transmitting the protozoan, highlighting their role as T. cruzi reservoirs.


Subject(s)
Chagas Disease , Lizards , Triatoma , Trypanosoma cruzi , Animals , Chagas Disease/veterinary , Insect Vectors
12.
Eur J Public Health ; 32(4): 565-570, 2022 08 01.
Article in English | MEDLINE | ID: mdl-35373832

ABSTRACT

BACKGROUND: The Health in Prisons European Database (HIPED) aims to periodically collect data on prison health systems, services and health outcomes to inform equivalence of care for people living in prison. Recognized as the United Nations hub for health data in prisons, HIPED lacked an established framework to define its domains and indicators to measure progress. Therefore, the objectives of developing this framework were to inform surveillance systems at prison, local, regional, national and international level and to use it to guide improvement of prison health systems and cross-country comparison. METHODS: The framework was conceptualized through identification of policy priorities and existing frameworks, notably the WHO Health System Framework. A consultation with a range of WHO stakeholders was conducted evaluating the components of existing frameworks and their relevance to the prison health context, as well as identifying areas needing further emphasis. The final stage identified the structure of the framework. RESULTS: The framework consists of three main building blocks. The first captures the system-level aspects of prison health care (or inputs) whilst the second captures delivery aspects of prison health care (or outputs). These building blocks are in turn modified by two influencing factors. Ultimately, all these elements impact on the third building block, health outcomes. In addition, two cross-cutting principles associated with all these building blocks and influencing factors are included. CONCLUSIONS: A new framework for assessing prison health system performance is now available, crucial to support informed decision-making for policy design and implementation for prisons and other places of detention.


Subject(s)
Prisoners , Prisons , Delivery of Health Care , Humans , Policy , World Health Organization
13.
Rev Bras Parasitol Vet ; 31(1): e018521, 2022.
Article in English | MEDLINE | ID: mdl-35019028

ABSTRACT

Ectoparasites of 18 free-living Cuban Ground Doves, Columbina passerina insularis (Columbiformes: Columbidae), captured in the National Zoological Park, Havana, Cuba, were identified. The collected ectoparasites included two species of lice (Phthiraptera: Ischnocera): Columbicola passerinae (77.1%), and Physconelloides eurysema (50%), as well as four species of feather mites (Astigmata: Falculiferidae): Pterophagus lomatus (83.3%), Byersalges talpacoti (50%), Byersalges phyllophorus (72.2%), and Hyperaspidacarus tridentatus (27.7%). Pterophagus lomatus, B. phyllophorus, and H. tridentatus represent new records for Cuba.


Subject(s)
Bird Diseases , Phthiraptera , Animals , Bird Diseases/epidemiology , Columbidae , Columbiformes , Cuba
14.
Rev. bras. parasitol. vet ; 31(1): e018521, 2022. graf
Article in English | LILACS, VETINDEX | ID: biblio-1357152

ABSTRACT

Abstract Ectoparasites of 18 free-living Cuban Ground Doves, Columbina passerina insularis (Columbiformes: Columbidae), captured in the National Zoological Park, Havana, Cuba, were identified. The collected ectoparasites included two species of lice (Phthiraptera: Ischnocera): Columbicola passerinae (77.1%), and Physconelloides eurysema (50%), as well as four species of feather mites (Astigmata: Falculiferidae): Pterophagus lomatus (83.3%), Byersalges talpacoti (50%), Byersalges phyllophorus (72.2%), and Hyperaspidacarus tridentatus (27.7%). Pterophagus lomatus, B. phyllophorus, and H. tridentatus represent new records for Cuba.


Resumo Foram identificados os ectoparasitas de 18 rolinhas-cinzentas de vida livre, Columbina passerina insularis (Columbiformes: Columbidae), capturadas no Parque Zoológico Nacional de Havana, Cuba. Os ectoparasitas coletados pertencem à duas espécies de piolhos (Phthiraptera: Ischnocera): Columbicola passerinae (77,1%) e Physconelloides eurysema (50%), bem como à quatro espé cies de ácaros de pena (Astigmata: Falculiferidae): Pterophagus lomatus (83,3%), Byersalges talpacoti (50%), Byersalges phyllophorus (72,2%) e Hyperaspidacarus tridentatus (27,7%). Pterophagus lomatus, B. phyllophorus e H. tridentatus representam novos registros para Cuba.


Subject(s)
Animals , Bird Diseases/epidemiology , Phthiraptera , Columbidae , Cuba , Columbiformes
15.
PLoS Comput Biol ; 17(12): e1009650, 2021 12.
Article in English | MEDLINE | ID: mdl-34898598

ABSTRACT

Academic graphs are essential for communicating complex scientific ideas and results. To ensure that these graphs truthfully reflect underlying data and relationships, visualization researchers have proposed several principles to guide the graph creation process. However, the extent of violations of these principles in academic publications is unknown. In this work, we develop a deep learning-based method to accurately measure violations of the proportional ink principle (AUC = 0.917), which states that the size of shaded areas in graphs should be consistent with their corresponding quantities. We apply our method to analyze a large sample of bar charts contained in 300K figures from open access publications. Our results estimate that 5% of bar charts contain proportional ink violations. Further analysis reveals that these graphical integrity issues are significantly more prevalent in some research fields, such as psychology and computer science, and some regions of the globe. Additionally, we find no temporal and seniority trends in violations. Finally, apart from openly releasing our large annotated dataset and method, we discuss how computational research integrity could be part of peer-review and the publication processes.


Subject(s)
Audiovisual Aids/standards , Biomedical Research/standards , Image Processing, Computer-Assisted/methods , Open Access Publishing/standards , Computer Graphics/standards , Databases, Factual , Humans , Reproducibility of Results
16.
Prim Health Care Res Dev ; 22: e81, 2021 12 16.
Article in English | MEDLINE | ID: mdl-34911588

ABSTRACT

AIMS: The aim of this paper is to introduce an operational checklist to serve as a tool for policymakers in the WHO European Region to strengthen primary health care (PHC) services and address the COVID-19 pandemic more effectively and to present the results from piloting the tool in Armenia. BACKGROUNDS: PHC has the potential to play a fundamental role in countries' responses to COVID-19. However, this potential remains unrealized in many countries. To assist countries, the WHO Regional Office for Europe developed a guidance document - Strengthening the Health Systems Response to COVID-19: Adapting Primary Health Care Services to more Effectively Address COVID-19 - that identifies strategic actions countries can take to strengthen their PHC response to the pandemic. Based on this guidance document, an operational checklist was developed to serve as a tool for policymakers to operationalize the recommended actions. METHODS: The operational checklist was developed by transforming key points in the guidance document into questions in order to identify potentially modifiable factors to strengthen PHC in response to COVID-19. The operational checklist was then piloted in Armenia in June 2020 as part of a WHO mission to provide technical advice on strengthening Armenia's PHC response to COVID-19. Two WHO experts performed semi-structured, face-to-face interviews with nine key informants (both facility managers and clinical staff) in three PHC facilities (two in a rural and one in an urban area). The data collected were analyzed to identify underlying challenges limiting PHC providers' ability to effectively and efficiently respond to COVID-19 and maintain essential health services. FINDINGS: The paper finds that making adjustments only to health services delivery will be insufficient to address most of the challenges identified by PHC providers in the context of COVID-19 in Armenia. In particular, strategic responses to the pandemic were missed, due, in part, to the absence of COVID-19 management teams at the facility level. Furthermore, the absence of PHC experts in Armenia's national pandemic response team meant that health system issues identified at the facility level could not easily be communicated to or addressed by policymakers. The checklist therefore helps policymakers identify critical challenges - at both the facility and health system level - that need to be addressed to strengthen the PHC response to the COVID-19 pandemic.


Subject(s)
COVID-19 , Armenia , Humans , Pandemics , Primary Health Care , SARS-CoV-2
17.
Rev Chilena Infectol ; 38(4): 548-554, 2021 Aug.
Article in Spanish | MEDLINE | ID: mdl-34652401

ABSTRACT

BACKGROUND: Rickettsioses are vector-borne emerging diseases caused by pathogenic bacteria of the genera Rickettsia and Orientia . Bacteria of these genera have been described in northern and southern Chile, respectively. AIM: To determine the presence of Rickettsia spp. in ticks collected from domestic dog in Rapa Nui-Easter Island, Valparaíso Region. METHODS: 20 stray dogs were sampled during October 2018. Overall, eight adult ticks were collected from seven animals (prevalence: 35%); after morphological identification, were submitted to DNA extraction and amplification and sequencing of the tick mitochondrial 16S DNA gene. The screening for Rickettsia was performed targeting the gltA (citrate synthetase) gene. RESULTS: A phylogenetic analysis confirmed the identity of the ticks as Rhipicephalus sanguineus sensu stricto. In two ticks (25%), we retrieved identical sequences of gltA compatible with " Candidatus Rickettsia andeanae", which formed a monophyletic group with conspecific isolates obtained in Brazil, Chile and Peru. CONCLUSION: This study proves the presence of " Ca . R. andeanae" in R. sanguineus s. s. at Rapa Nui-Easter Island, which also corresponds to the first report of this Rickettsia spp. in R. sanguineus complex for Chile.


Subject(s)
Dog Diseases , Ixodidae , Rhipicephalus sanguineus , Rickettsia Infections , Rickettsia , Animals , Dogs , Phylogeny , Rickettsia/genetics , Rickettsia Infections/veterinary
18.
Rev Bras Parasitol Vet ; 30(3): e004221, 2021.
Article in English | MEDLINE | ID: mdl-34378768

ABSTRACT

Invasive species impact native wildlife in several ways, as they compete for resources and may transmit their specific pathogens. However, the potential consequences of co-introduced parasites are not fully understood. While the house sparrow (Passer domesticus) was introduced in Chile about a century ago, no data are available regarding its parasites. Thus, the aim of the present study was to determine the parasitic fauna of this avian invader and to determine whether there are co-introduced/co-invasive parasites shared with native birds. One hundred and eight birds were collected from three different localities in the Ñuble region of Chile, and a complete parasitic necropsy was performed in the laboratory. Twenty-three (21.3%) were parasitized by six arthropod species and four (3.7%) were parasitized by two helminth species. Four out of eight taxa are reported for the first time in Chile; among them, three arthropod parasites and the tapeworm, Anonchotaenia globate, are considered as co-introduced parasites. Only A. globata is a potential co-invasive parasite given its low degree specificity in terms of its definitive hosts. Future research should examine whether additional co-introduced/co-invasive parasites have been brought by the house sparrow, and what their potential consequences might be on the health of native birds in Chile.


Subject(s)
Parasites , Sparrows , Animals , Animals, Wild , Chile , Introduced Species
19.
Rev. chil. infectol ; 38(4): 548-554, ago. 2021. ilus
Article in Spanish | LILACS | ID: biblio-1388270

ABSTRACT

INTRODUCCIÓN: Las rickettsiosis son enfermedades emergentes transmitidas por vectores artrópodos cuyos agentes etiológicos corresponden a bacterias patógenas del género Rickettsia y Orientia . Bacterias de este género han sido descritas en el norte y sur de Chile. OBJETIVO: Determinar presencia de Rickettsia spp. en garrapatas colectadas a partir de perros domésticos en Rapa Nui-Isla de Pascua, Región de Valparaíso. MÉTODOS: Fueron muestreados 20 perros callejeros durante octubre del año 2018. Se colectaron ocho garrapatas adultas desde siete animales (prevalencia: 35%); luego de su identificación taxonómica fueron sometidas a amplificación y secuenciación del gen ADNm 16S para garrapata y gltA (citrato sintetasa) para Rickettsia . RESULTADOS: Todos los ejemplares de garrapatas adultas correspondieron genéticamente a Rhipicephalus sanguineus sensu stricto lo cual fue confirmado mediante un análisis filogenético. En dos garrapatas (25%) se encontraron secuencias idénticas de gltA compatibles con " Candidatus Rickettsia andeanae", que formaron un clado monofilético con aislados obtenidos en Brasil, Chile y Perú. CONCLUSIÓN: Se documenta la presencia de " Ca. R. andeanae" s. s. en Rapa Nui-Isla de Pascua, asociado por primera vez a garrapatas del complejo R. sanguineus en Chile.


BACKGROUND: Rickettsioses are vector-borne emerging diseases caused by pathogenic bacteria of the genera Rickettsia and Orientia . Bacteria of these genera have been described in northern and southern Chile, respectively. AIM: To determine the presence of Rickettsia spp. in ticks collected from domestic dog in Rapa Nui-Easter Island, Valparaíso Region. METHODS: 20 stray dogs were sampled during October 2018. Overall, eight adult ticks were collected from seven animals (prevalence: 35%); after morphological identification, were submitted to DNA extraction and amplification and sequencing of the tick mitochondrial 16S DNA gene. The screening for Rickettsia was performed targeting the gltA (citrate synthetase) gene. RESULTS: A phylogenetic analysis confirmed the identity of the ticks as Rhipicephalus sanguineus sensu stricto. In two ticks (25%), we retrieved identical sequences of gltA compatible with " Candidatus Rickettsia andeanae", which formed a monophyletic group with conspecific isolates obtained in Brazil, Chile and Peru. CONCLUSION: This study proves the presence of " Ca . R. andeanae" in R. sanguineus s. s. at Rapa Nui-Easter Island, which also corresponds to the first report of this Rickettsia spp. in R. sanguineus complex for Chile.


Subject(s)
Animals , Dogs , Rickettsia/genetics , Rickettsia Infections/veterinary , Rhipicephalus sanguineus/microbiology , Dog Diseases , Phylogeny
20.
Int J Parasitol ; 51(11): 899-911, 2021 10.
Article in English | MEDLINE | ID: mdl-34044005

ABSTRACT

The specialist versus generalist strategies of hemoparasites in relation to their avian host, as well as environmental factors, can influence their prevalence, diversity and distribution. In this paper we investigated the influence of avian host species, as well as the environmental and geographical factors, on the strategies of Haemoproteus and Plasmodium hemoparasites. We determined prevalence and diversity by targeting their cytochrome b (Cytb) in a total of 2,590 passerine samples from 138 localities of Central and South America, and analysed biogeographic patterns and host-parasite relationships. We found a total prevalence of 23.2%. Haemoproteus presented a higher prevalence (15.3%) than Plasmodium (4.3%), as well as a higher diversity and host specificity. We determined that Plasmodium and Haemoproteus prevalences correlated positively with host diversity (Shannon index) and were significantly influenced by bird diversity, demonstrating a possible "amplification effect". We found an effect of locality and the avian family for prevalences of Haemoproteus and Plasmodium. These results suggest that Haemoproteus is more specialist than Plasmodium and could be mostly influenced by its avian host and the Andes Mountains.


Subject(s)
Bird Diseases , Haemosporida , Malaria, Avian , Parasites , Plasmodium , Protozoan Infections, Animal , Animals , Bird Diseases/epidemiology , Haemosporida/genetics , Malaria, Avian/epidemiology , Phylogeny , Plasmodium/genetics , Prevalence
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