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1.
Opt Express ; 29(8): 12240-12251, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33984988

RESUMO

In a recent experimental campaign, we used laser-accelerated relativistic hot electrons to ensure heating of thin titanium wire targets up to a warm dense matter (WDM) state [EPL114, 45002 (2016)10.1209/0295-5075/114/45002]. The WDM temperature profiles along several hundred microns of the wire were inferred by using spatially resolved X-ray emission spectroscopy looking at the Ti Kα characteristic lines. A maximum temperature of ∼30 eV was reached. Our study extends this work by discussing the influence of the laser parameters on temperature profiles and the optimisation of WDM wire-based generation. The depth of wire heating may reach several hundreds of microns and it is proven to be strictly dependent on the laser intensity. At the same time, it is quantitatively demonstrated that the maximum WDM temperature doesn't appear to be sensitive to the laser intensity and mainly depends on the deposited laser energy considering ranges of 6×1018-6×1020 W/cm2 and 50-200 J.

2.
Proc Natl Acad Sci U S A ; 117(46): 29190-29201, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33139552

RESUMO

Nipah virus (NiV) is an emerging bat-borne zoonotic virus that causes near-annual outbreaks of fatal encephalitis in South Asia-one of the most populous regions on Earth. In Bangladesh, infection occurs when people drink date-palm sap contaminated with bat excreta. Outbreaks are sporadic, and the influence of viral dynamics in bats on their temporal and spatial distribution is poorly understood. We analyzed data on host ecology, molecular epidemiology, serological dynamics, and viral genetics to characterize spatiotemporal patterns of NiV dynamics in its wildlife reservoir, Pteropus medius bats, in Bangladesh. We found that NiV transmission occurred throughout the country and throughout the year. Model results indicated that local transmission dynamics were modulated by density-dependent transmission, acquired immunity that is lost over time, and recrudescence. Increased transmission followed multiyear periods of declining seroprevalence due to bat-population turnover and individual loss of humoral immunity. Individual bats had smaller host ranges than other Pteropus species (spp.), although movement data and the discovery of a Malaysia-clade NiV strain in eastern Bangladesh suggest connectivity with bats east of Bangladesh. These data suggest that discrete multiannual local epizootics in bat populations contribute to the sporadic nature of NiV outbreaks in South Asia. At the same time, the broad spatial and temporal extent of NiV transmission, including the recent outbreak in Kerala, India, highlights the continued risk of spillover to humans wherever they may interact with pteropid bats and the importance of limiting opportunities for spillover throughout Pteropus's range.


Assuntos
Quirópteros/virologia , Infecções por Henipavirus/epidemiologia , Infecções por Henipavirus/transmissão , Infecções por Henipavirus/veterinária , Infecções por Henipavirus/virologia , Vírus Nipah/classificação , Vírus Nipah/genética , Animais , Ásia , Bangladesh/epidemiologia , Surtos de Doenças , Feminino , Especificidade de Hospedeiro , Humanos , Imunidade , Masculino , Modelos Biológicos , Epidemiologia Molecular , Vírus Nipah/imunologia , Filogenia , Zoonoses/epidemiologia , Zoonoses/imunologia , Zoonoses/transmissão , Zoonoses/virologia
3.
Nat Commun ; 11(1): 4235, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32843626

RESUMO

Bats are presumed reservoirs of diverse coronaviruses (CoVs) including progenitors of Severe Acute Respiratory Syndrome (SARS)-CoV and SARS-CoV-2, the causative agent of COVID-19. However, the evolution and diversification of these coronaviruses remains poorly understood. Here we use a Bayesian statistical framework and a large sequence data set from bat-CoVs (including 630 novel CoV sequences) in China to study their macroevolution, cross-species transmission and dispersal. We find that host-switching occurs more frequently and across more distantly related host taxa in alpha- than beta-CoVs, and is more highly constrained by phylogenetic distance for beta-CoVs. We show that inter-family and -genus switching is most common in Rhinolophidae and the genus Rhinolophus. Our analyses identify the host taxa and geographic regions that define hotspots of CoV evolutionary diversity in China that could help target bat-CoV discovery for proactive zoonotic disease surveillance. Finally, we present a phylogenetic analysis suggesting a likely origin for SARS-CoV-2 in Rhinolophus spp. bats.


Assuntos
Quirópteros/virologia , Infecções por Coronavirus/veterinária , Coronavirus/genética , Evolução Molecular , Zoonoses/transmissão , Animais , Teorema de Bayes , Betacoronavirus/classificação , Betacoronavirus/genética , Biodiversidade , COVID-19 , China , Quirópteros/classificação , Coronavirus/classificação , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Humanos , Pandemias , Filogenia , Filogeografia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , SARS-CoV-2 , Zoonoses/virologia
4.
BMC Biol ; 18(1): 101, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32819385

RESUMO

BACKGROUND: Effective conservation management of highly mobile species depends upon detailed knowledge of movements of individuals across their range; yet, data are rarely available at appropriate spatiotemporal scales. Flying-foxes (Pteropus spp.) are large bats that forage by night on floral resources and rest by day in arboreal roosts that may contain colonies of many thousands of individuals. They are the largest mammals capable of powered flight, and are highly mobile, which makes them key seed and pollen dispersers in forest ecosystems. However, their mobility also facilitates transmission of zoonotic diseases and brings them in conflict with humans, and so they require a precarious balancing of conservation and management concerns throughout their Old World range. Here, we analyze the Australia-wide movements of 201 satellite-tracked individuals, providing unprecedented detail on the inter-roost movements of three flying-fox species: Pteropus alecto, P. poliocephalus, and P. scapulatus across jurisdictions over up to 5 years. RESULTS: Individuals were estimated to travel long distances annually among a network of 755 roosts (P. alecto, 1427-1887 km; P. poliocephalus, 2268-2564 km; and P. scapulatus, 3782-6073 km), but with little uniformity among their directions of travel. This indicates that flying-fox populations are composed of extremely mobile individuals that move nomadically and at species-specific rates. Individuals of all three species exhibited very low fidelity to roosts locally, resulting in very high estimated daily colony turnover rates (P. alecto, 11.9 ± 1.3%; P. poliocephalus, 17.5 ± 1.3%; and P. scapulatus, 36.4 ± 6.5%). This indicates that flying-fox roosts form nodes in a vast continental network of highly dynamic "staging posts" through which extremely mobile individuals travel far and wide across their species ranges. CONCLUSIONS: The extreme inter-roost mobility reported here demonstrates the extent of the ecological linkages that nomadic flying-foxes provide across Australia's contemporary fragmented landscape, with profound implications for the ecosystem services and zoonotic dynamics of flying-fox populations. In addition, the extreme mobility means that impacts from local management actions can readily reverberate across jurisdictions throughout the species ranges; therefore, local management actions need to be assessed with reference to actions elsewhere and hence require national coordination. These findings underscore the need for sound understanding of animal movement dynamics to support evidence-based, transboundary conservation and management policy, tailored to the unique movement ecologies of species.


Assuntos
Tamanho Corporal , Quirópteros/fisiologia , Conservação dos Recursos Naturais , Voo Animal , Animais , Austrália , Movimento , Tecnologia de Sensoriamento Remoto/veterinária
5.
bioRxiv ; 2020 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-32577651

RESUMO

Bats are presumed reservoirs of diverse coronaviruses (CoVs) including progenitors of Severe Acute Respiratory Syndrome (SARS)-CoV and SARS-CoV-2, the causative agent of COVID-19. However, the evolution and diversification of these coronaviruses remains poorly understood. We used a Bayesian statistical framework and sequence data from all known bat-CoVs (including 630 novel CoV sequences) to study their macroevolution, cross-species transmission, and dispersal in China. We find that host-switching was more frequent and across more distantly related host taxa in alpha-than beta-CoVs, and more highly constrained by phylogenetic distance for beta-CoVs. We show that inter-family and -genus switching is most common in Rhinolophidae and the genus Rhinolophus . Our analyses identify the host taxa and geographic regions that define hotspots of CoV evolutionary diversity in China that could help target bat-CoV discovery for proactive zoonotic disease surveillance. Finally, we present a phylogenetic analysis suggesting a likely origin for SARS-CoV-2 in Rhinolophus spp. bats.

6.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-116061

RESUMO

Bats are presumed reservoirs of diverse coronaviruses (CoVs) including progenitors of Severe Acute Respiratory Syndrome (SARS)-CoV and SARS-CoV-2, the causative agent of COVID-19. However, the evolution and diversification of these coronaviruses remains poorly understood. We used a Bayesian statistical framework and sequence data from all known bat-CoVs (including 630 novel CoV sequences) to study their macroevolution, cross-species transmission, and dispersal in China. We find that host-switching was more frequent and across more distantly related host taxa in alpha-than beta-CoVs, and more highly constrained by phylogenetic distance for beta-CoVs. We show that inter-family and -genus switching is most common in Rhinolophidae and the genus Rhinolophus. Our analyses identify the host taxa and geographic regions that define hotspots of CoV evolutionary diversity in China that could help target bat-CoV discovery for proactive zoonotic disease surveillance. Finally, we present a phylogenetic analysis suggesting a likely origin for SARS-CoV-2 in Rhinolophus spp. bats.

7.
Zoonoses Public Health ; 67(4): 435-442, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32311218

RESUMO

In November 2017, two groups of P. conspicillatus pups from separate locations in Far North Queensland presented with neurological signs consistent with Australian bat lyssavirus (ABLV) infection. These pups (n = 11) died over an 11-day period and were submitted to a government laboratory for testing where ABLV infection was confirmed. Over the next several weeks, additional ABLV cases in flying foxes in Queensland were also detected. Brain tissue from ABLV-infected flying foxes during this period, as well as archived brain tissue, was selected for next-generation sequencing. Phylogenetic analysis suggests that the two groups of pups were each infected from single sources. They were likely exposed while in crèche at night as their dams foraged. This study identifies crèche-age pups at a potentially heightened risk for mass ABLV infection.


Assuntos
Quirópteros/virologia , Surtos de Doenças/veterinária , Lyssavirus/isolamento & purificação , Infecções por Rhabdoviridae/veterinária , Animais , Genoma Viral , Lyssavirus/genética , Queensland/epidemiologia , Infecções por Rhabdoviridae/epidemiologia , Infecções por Rhabdoviridae/virologia
8.
Bone Joint J ; 99-B(12): 1603-1610, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29212683

RESUMO

AIMS: To evaluate the effectiveness of an institutionally developed algorithm for evaluation and diagnosis of prosthetic joint injection and to determine the impact of this protocol on overall hospital re-admissions.p PATIENTS AND METHODS: We retrospectively evaluated 2685 total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients prior to (1263) and following (1422) the introduction of an infection detection protocol. The protocol used conservative thresholds for C-reactive protein to direct the medical attendant to aspirate the joint. The protocol incorporated a clear set of laboratory and clinical criteria that allowed a patient to be discharged home if all were met. Patients were included if they presented to our emergency department within 120 days post-operatively with concerns for swelling, pain or infection and were excluded if they had an unambiguous infection or if their chief complaint was non-orthopaedic in nature. RESULTS: Concern for infection was the single most common (32%) reason for presentation. A total of 296 patients made an emergency visit and were included following THA or TKA. In the pre-protocol cohort, 11 of 27 patients were formally re-admitted to the hospital with concern for infection but only five (45%) patients had actual infections and received additional treatment. In comparison, in the post-protocol cohort, 11 patients were admitted for suspected infection, nine (82%) of whom were truly infected (p = 0.04). Sensitivity increased from 83% to 100% and specificity increased from 71% to 96%. Implementation of this protocol did not miss any infections. CONCLUSION: A standardised protocol for evaluation of THA and TKA infections significantly reduced unnecessary hospital re-admissions. The protocol was both sensitive and specific and did not compromise quality of care. Cite this article: Bone Joint J 2017;99-B:1603-10.


Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Protocolos Clínicos/normas , Readmissão do Paciente/estatística & dados numéricos , Infecções Relacionadas à Prótese/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Proteína C-Reativa/análise , Feminino , Humanos , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Infecções Relacionadas à Prótese/etiologia , Estudos Retrospectivos , Líquido Sinovial/química , Líquido Sinovial/imunologia
9.
Prev Vet Med ; 148: 28-36, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29157371

RESUMO

In recent years, outbreaks of exotic as well as newly emerging infectious diseases have highlighted the importance of biosecurity for the Australian horse industry. As the first potentially fatal zoonosis transmissible from horses to humans in Australia, Hendra virus has emphasised the need to incorporate sound hygiene and general biosecurity practices into day-to-day horse management. Recommended measures are widely publicised, but implementation is at the discretion of the individual owner. This cross-sectional study aimed to determine current levels of biosecurity of horse owners and to identify factors influencing the uptake of practices utilising data from an online survey. Level of biosecurity (low, medium, high), as determined by horse owners' responses to a set of questions on the frequency of various biosecurity practices performed around healthy (9 items) and sick horses (10 items), was used as a composite outcome variable in ordinal logistic regression analyses. The majority of horse owners surveyed were female (90%), from the states of Queensland (45%) or New South Wales (37%), and were involved in either mainly competitive/equestrian sports (37%) or recreational horse activities (35%). Seventy-five percent of owners indicated that they follow at least one-third of the recommended practices regularly when handling their horses, resulting in medium to high levels of biosecurity. Main factors associated with a higher level of biosecurity were high self-rated standard of biosecurity, access to personal protective equipment, absence of flying foxes in the local area, a good sense of control over Hendra virus risk, likelihood of discussing a sick horse with a veterinarian and likelihood of suspecting Hendra virus in a sick horse. Comparison of the outcome variable with the self-rated standard of biosecurity showed that over- as well as underestimation occurred. This highlights the need for continuous communication and education to enhance awareness and understanding of what biosecurity is and how it aligns with good horsemanship. Overall, strengthened biosecurity practices will help to improve animal as well as human health and increase preparedness for future disease outbreaks.


Assuntos
Comunicação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Vírus Hendra/fisiologia , Infecções por Henipavirus/veterinária , Doenças dos Cavalos/prevenção & controle , Zoonoses/prevenção & controle , Animais , Austrália , Estudos Transversais , Infecções por Henipavirus/prevenção & controle , Infecções por Henipavirus/psicologia , Infecções por Henipavirus/virologia , Doenças dos Cavalos/psicologia , Doenças dos Cavalos/virologia , Cavalos , Humanos , Zoonoses/psicologia , Zoonoses/virologia
10.
Prev Vet Med ; 140: 67-77, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28460752

RESUMO

Hendra virus causes sporadic zoonotic disease in Australia following spill over from flying foxes to horses and from horses to people. Prevention and risk mitigation strategies such as vaccination of horses or biosecurity and property management measures are widely publicised, but hinge on initiative and action taken by horse owners as they mediate management, care and treatment of their animals. Hence, underlying beliefs, values and attitudes of horse owners influence their uptake of recommended risk mitigation measures. We used a qualitative approach to investigate attitudes, perceptions and self-reported practices of horse owners in response to Hendra virus to gain a deeper understanding of their decision-making around prevention measures. Data presented here derive from a series of in-depth interviews with 27 horse owners from Hendra virus 'hot spot' areas in New South Wales and Queensland. Interviews explored previous experience, perceptions and resulting behaviour as well as communication around Hendra virus. All interviews were recorded, transcribed verbatim and analysed in NVivo using thematic analysis. Analysis revealed four major themes: perception of Hendra virus as a risk and factors influencing this perception, Hendra virus risk mitigation strategies implemented by horse owners, perceived motivators and barriers of these strategies, and interaction of perceived risk, motivators and barriers in the decision-making process. Although Hendra virus disease was perceived as a serious threat to the health of horses and humans, individual risk perception diverged among horse owners. Perceived severity, likelihood and unpredictability as well as awareness and knowledge of Hendra virus, trust in information obtained and information pathways, demographic characteristics and personal experience were the main factors influencing Hendra virus risk perceptions. Other key determinants of horse owners' decision-making process were attitudes towards Hendra virus risk mitigation measures as well as perceived motivators and barriers thereof. Horse owners' awareness of the necessity to consider individual Hendra virus risk and adequate risk management strategies was described as a learning process, which changed over time. However, different perceptions of risk, barriers and motivators in combination with a weighing up of advantages and disadvantages resulted in different behaviours. These findings demonstrate the multifactorial determinants of cognitive mediating processes and facilitate a better understanding of horse owners' perspectives on preventive horse health measures. Furthermore, they provide valuable feedback to industry and government stakeholders on how to improve effective risk communication and encourage uptake of recommended risk mitigation measures.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Infecções por Henipavirus/veterinária , Doenças dos Cavalos/prevenção & controle , Doenças dos Cavalos/psicologia , Adulto , Idoso , Criação de Animais Domésticos , Animais , Austrália , Quirópteros/virologia , Tomada de Decisões , Feminino , Vírus Hendra , Infecções por Henipavirus/prevenção & controle , Infecções por Henipavirus/psicologia , Doenças dos Cavalos/virologia , Cavalos , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , New South Wales/epidemiologia , Queensland/epidemiologia , Fatores de Risco , Vacinação/psicologia , Adulto Jovem
12.
Curr Opin Virol ; 16: 120-125, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26978066

RESUMO

Hendra virus causes acute and highly fatal infection in horses and humans. Pteropid bats (flying-foxes) are the natural host of the virus, with age and species being risk factors for infection. Urine is the primary route of excretion in flying-foxes, with viral RNA more frequently detected in Pteropus alecto and P. conspicillatus than other species. Infection prevalence in flying-foxes can vary between and within years, with a winter peak of excretion occurring in some regions. Vertical transmission and recrudescing infection has been reported in flying-foxes, but horizontal transmission is evidently the primary mode of transmission. The most parsimonious mode of flying-fox to horse transmission is equine contact (oro-nasal, conjunctival) with infected flying-fox urine, either directly, or via urine-contaminated pasture or surfaces. Horse to horse transmission is inefficient, requiring direct contact with infected body fluids. Flying-fox to human transmission has not been recorded; all human cases have been associated with close and direct contact with infected horses. Canine cases (subclinical) have also been limited to equine case properties. Notwithstanding the recent availability of an effective vaccine for horses, a comprehensive understanding of Hendra virus ecology and transmission is essential to limit inter-species transmission.


Assuntos
Vírus Hendra/fisiologia , Infecções por Henipavirus/transmissão , Infecções por Henipavirus/virologia , Animais , Quirópteros , Infecções por Henipavirus/epidemiologia , Cavalos , Humanos , Zoonoses/epidemiologia , Zoonoses/transmissão , Zoonoses/virologia
13.
Bone Joint J ; 97-B(11): 1512-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26530654

RESUMO

Older patients with multiple medical co-morbidities are increasingly being offered and undergoing total joint arthroplasty (TJA). These patients are more likely to require intensive care support, following surgery. We prospectively evaluated the need for intensive care admission and intervention in a consecutive series of 738 patients undergoing elective hip and knee arthroplasty procedures. The mean age was 60.6 years (18 to 91; 440 women, 298 men. Risk factors, correlating with the need for critical care intervention, according to published guidelines, were analysed to identify high-risk patients who would benefit from post-operative critical care monitoring. A total of 50 patients (6.7%) in our series required critical care level interventions during their hospital stay. Six independent multivariate clinical predictors were identified (p < 0.001) including a history of congestive heart failure (odds ratio (OR) 24.26, 95% confidence interval (CI) 9.51 to 61.91), estimated blood loss > 1000 mL (OR 17.36, 95% CI 5.36 to 56.19), chronic obstructive pulmonary disease (13.90, 95% CI 4.78 to 40.36), intra-operative use of vasopressors (OR 8.10, 95% CI 3.23 to 20.27), revision hip arthroplasty (OR 2.71, 95% CI 1.04 to 7.04) and body mass index > 35 kg/m(2) (OR 2.70, 95% CI 123 to 5.94). The model was then validated against an independent, previously published data set of 1594 consecutive patients. The use of this risk stratification model can be helpful in predicting which high-risk patients would benefit from a higher level of monitoring and care after elective TJA and aid hospitals in allocating precious critical care resources.


Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Cuidados Críticos/organização & administração , Cuidados Pós-Operatórios/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/métodos , Artroplastia do Joelho/métodos , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Admissão do Paciente/estatística & dados numéricos , Philadelphia , Estudos Prospectivos , Medição de Risco/métodos , Fatores de Risco , Adulto Jovem
14.
Virol J ; 12: 107, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-26184657

RESUMO

BACKGROUND: In 2008-09, evidence of Reston ebolavirus (RESTV) infection was found in domestic pigs and pig workers in the Philippines. With species of bats having been shown to be the cryptic reservoir of filoviruses elsewhere, the Philippine government, in conjunction with the Food and Agriculture Organization of the United Nations, assembled a multi-disciplinary and multi-institutional team to investigate Philippine bats as the possible reservoir of RESTV. METHODS: The team undertook surveillance of bat populations at multiple locations during 2010 using both serology and molecular assays. RESULTS: A total of 464 bats from 21 species were sampled. We found both molecular and serologic evidence of RESTV infection in multiple bat species. RNA was detected with quantitative PCR (qPCR) in oropharyngeal swabs taken from Miniopterus schreibersii, with three samples yielding a product on conventional hemi-nested PCR whose sequences differed from a Philippine pig isolate by a single nucleotide. Uncorroborated qPCR detections may indicate RESTV nucleic acid in several additional bat species (M. australis, C. brachyotis and Ch. plicata). We also detected anti-RESTV antibodies in three bats (Acerodon jubatus) using both Western blot and ELISA. CONCLUSIONS: The findings suggest that ebolavirus infection is taxonomically widespread in Philippine bats, but the evident low prevalence and low viral load warrants expanded surveillance to elaborate the findings, and more broadly, to determine the taxonomic and geographic occurrence of ebolaviruses in bats in the region.


Assuntos
Quirópteros/virologia , Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/veterinária , Animais , Anticorpos Antivirais/sangue , Análise por Conglomerados , Ensaio de Imunoadsorção Enzimática , Doença pelo Vírus Ebola/virologia , Orofaringe/virologia , Filipinas , Filogenia , RNA Viral/genética , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Homologia de Sequência
15.
PLoS One ; 10(6): e0128835, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26060997

RESUMO

Hendra virus (HeV) is a lethal zoonotic agent that emerged in 1994 in Australia. Pteropid bats (flying-foxes) are the natural reservoir. To date, HeV has spilled over from flying-foxes to horses on 51 known occasions, and from infected horses to close-contact humans on seven occasions. We undertook screening of archived bat tissues for HeV by reverse transcription quantitative polymerase chain reaction (RT-qPCR). Tissues were tested from 310 bats including 295 Pteropodiformes and 15 Vespertilioniformes. HeV was detected in 20 individual flying-foxes (6.4%) from various tissues including spleen, kidney, liver, lung, placenta and blood components. Detection was significantly higher in Pteropus Alecto and P. conspicillatus, identifying species as a risk factor for infection. Further, our findings indicate that HeV has a predilection for the spleen, suggesting this organ plays an important role in HeV infection. The lack of detections in the foetal tissues of HeV-positive females suggests that vertical transmission is not a regular mode of transmission in naturally infected flying-foxes, and that placental and foetal tissues are not a major source of infection for horses. A better understanding of HeV tissue tropism will strengthen management of the risk of spillover from flying-foxes to horses and ultimately humans.


Assuntos
Quirópteros/virologia , Vírus Hendra/isolamento & purificação , Infecções por Henipavirus/patologia , Tropismo Viral , Zoonoses/virologia , Animais , Quirópteros/classificação , Feminino , Vírus Hendra/fisiologia , Infecções por Henipavirus/epidemiologia , Infecções por Henipavirus/virologia , Masculino , Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Especificidade da Espécie
16.
J Gen Virol ; 96(Pt 7): 1619-25, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25701824

RESUMO

Understanding the diversity of henipaviruses and related viruses is important in determining the viral ecology within flying-fox populations and assessing the potential threat posed by these agents. This study sought to identify the abundance and diversity of previously unknown paramyxoviruses (UPVs) in Australian flying-fox species (Pteropus alecto, Pteropus scapulatus, Pteropus poliocephalus and Pteropus conspicillatus) and in the Christmas Island species Pteropus melanotus natalis. Using a degenerative reverse transcription-PCR specific for the L gene of known species of the genus Henipavirus and two closely related paramyxovirus genera Respirovirus and Morbillivirus, we identified an abundance and diversity of previously UPVs, with a representative 31 UPVs clustering in eight distinct groups (100 UPVs/495 samples). No new henipaviruses were identified. The findings were consistent with a hypothesis of co-evolution of paramyxoviruses and their flying-fox hosts. Quantification of the degree of co-speciation between host and virus (beyond the scope of this study) would strengthen this hypothesis.


Assuntos
Evolução Biológica , Quirópteros/virologia , Variação Genética , Interações Hospedeiro-Patógeno , Paramyxoviridae/classificação , Paramyxoviridae/isolamento & purificação , Animais , Análise por Conglomerados , Dados de Sequência Molecular , Paramyxoviridae/genética , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência
17.
One Health ; 1: 24-30, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28616461

RESUMO

The urban presence of flying-foxes (pteropid bats) in eastern Australia has increased in the last 20 years, putatively reflecting broader landscape change. The influx of large numbers often precipitates community angst, typically stemming from concerns about loss of social amenity, economic loss or negative health impacts from recently emerged bat-mediated zoonotic diseases such as Hendra virus and Australian bat lyssavirus. Local authorities and state wildlife authorities are increasingly asked to approve the dispersal or modification of flying-fox roosts to address expressed concerns, yet the scale of this concern within the community, and the veracity of the basis for concern are often unclear. We conducted an on-line survey to capture community attitudes and opinions on flying-foxes in the urban environment to inform management policy and decision-making. Analysis focused on awareness, concerns, and management options, and primarily compared responses from communities where flying-fox management was and was not topical at the time of the survey. While a majority of respondents indicated a moderate to high level of knowledge of both flying-foxes and Hendra virus, a substantial minority mistakenly believed that flying-foxes pose a direct infection risk to humans, suggesting miscommunication or misinformation, and the need for additional risk communication strategies. Secondly, a minority of community members indicated they were directly impacted by urban roosts, most plausibly those living in close proximity to the roost, suggesting that targeted management options are warranted. Thirdly, neither dispersal nor culling was seen as an appropriate management strategy by the majority of respondents, including those from postcodes where flying-fox management was topical. These findings usefully inform community debate and policy development and demonstrate the value of social analysis in defining the issues and options in this complex human-wildlife interaction. The mobile nature of flying-foxes underlines the need for a management strategy at a regional or larger scale, and independent of state borders.

18.
PLoS One ; 8(11): e80430, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24312221

RESUMO

Zoonoses from wildlife threaten global public health. Hendra virus is one of several zoonotic viral diseases that have recently emerged from Pteropus species fruit-bats (flying-foxes). Most hypotheses regarding persistence of Hendra virus within flying-fox populations emphasize horizontal transmission within local populations (colonies) via urine and other secretions, and transmission among colonies via migration. As an alternative hypothesis, we explore the role of recrudescence in persistence of Hendra virus in flying-fox populations via computer simulation using a model that integrates published information on the ecology of flying-foxes, and the ecology and epidemiology of Hendra virus. Simulated infection patterns agree with infection patterns observed in the field and suggest that Hendra virus could be maintained in an isolated flying-fox population indefinitely via periodic recrudescence in a manner indistinguishable from maintenance via periodic immigration of infected individuals. Further, post-recrudescence pulses of infectious flying-foxes provide a plausible basis for the observed seasonal clustering of equine cases. Correct understanding of the infection dynamics of Hendra virus in flying-foxes is fundamental to effectively managing risk of infection in horses and humans. Given the lack of clear empirical evidence on how the virus is maintained within populations, the role of recrudescence merits increased attention.


Assuntos
Quirópteros/virologia , Infecções por Henipavirus/veterinária , Zoonoses/epidemiologia , Animais , Austrália , Meio Ambiente , Feminino , Vírus Hendra , Masculino , Modelos Teóricos , Dinâmica Populacional , Zoonoses/virologia
19.
Bone Joint J ; 95-B(11 Suppl A): 74-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24187358

RESUMO

Patient safety is a critical issue in elective total joint replacement surgery. Identifying risk factors that might predict complications and intensive care unit (ICU) admission proves instrumental in reducing morbidity and mortality. The institution's experience with risk stratification and pre-operative ICU triage has resulted in a reduction in unplanned ICU admissions and post-operative complications after total hip replacement. The application of the prediction tools to total knee replacement has proven less robust so far. This work also reviews areas for future research in patient safety and cost containment.


Assuntos
Artroplastia de Substituição , Unidades de Terapia Intensiva , Complicações Pós-Operatórias/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia do Joelho , Controle de Custos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Triagem
20.
PLoS One ; 8(4): e61316, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23637812

RESUMO

Nipah virus (NiV) (Genus Henipavirus) is a recently emerged zoonotic virus that causes severe disease in humans and has been found in bats of the genus Pteropus. Whilst NiV has not been detected in Australia, evidence for NiV-infection has been found in pteropid bats in some of Australia's closest neighbours. The aim of this study was to determine the occurrence of henipaviruses in fruit bat (Family Pteropodidae) populations to the north of Australia. In particular we tested the hypothesis that Nipah virus is restricted to west of Wallace's Line. Fruit bats from Australia, Papua New Guinea, East Timor and Indonesia were tested for the presence of antibodies to Hendra virus (HeV) and Nipah virus, and tested for the presence of HeV, NiV or henipavirus RNA by PCR. Evidence was found for the presence of Nipah virus in both Pteropus vampyrus and Rousettus amplexicaudatus populations from East Timor. Serology and PCR also suggested the presence of a henipavirus that was neither HeV nor NiV in Pteropus alecto and Acerodon celebensis. The results demonstrate the presence of NiV in the fruit bat populations on the eastern side of Wallace's Line and within 500 km of Australia. They indicate the presence of non-NiV, non-HeV henipaviruses in fruit bat populations of Sulawesi and Sumba and possibly in Papua New Guinea. It appears that NiV is present where P. vampyrus occurs, such as in the fruit bat populations of Timor, but where this bat species is absent other henipaviruses may be present, as on Sulawesi and Sumba. Evidence was obtained for the presence henipaviruses in the non-Pteropid species R. amplexicaudatus and in A. celebensis. The findings of this work fill some gaps in knowledge in geographical and species distribution of henipaviruses in Australasia which will contribute to planning of risk management and surveillance activities.


Assuntos
Doenças dos Animais/epidemiologia , Quirópteros/virologia , Infecções por Henipavirus/veterinária , Vírus Nipah , Animais , Sudeste Asiático/epidemiologia , Australásia/epidemiologia , Vírus Hendra/genética , Vírus Hendra/imunologia , Humanos , Masculino , Vírus Nipah/genética , Vírus Nipah/imunologia
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