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Serpentoviruses are strongly associated with upper respiratory tract disease in captive and free-ranging bluetongued skinks (Tiliqua spp.). In Australia, bluetongue serpentoviruses were first reported in shingleback skinks (Tiliqua rugosa) with upper respiratory tract disease that presented to wildlife rehabilitation facilities in Perth, Western Australia. Since then, serpentoviruses have been detected commonly in captive bluetongued skinks from most areas of Australia, yet knowledge about the prevalence and distribution of these viruses in free-ranging bluetongued skinks, and other skink species, remains limited. Oral swabs were collected from 162 shingleback skinks from four areas in Western Australia and neighboring South Australia to screen for bluetongue serpentoviruses by PCR. The proportions of PCR positives were 0% (0/4) for Rottnest Island (a small island west of Perth, Western Australia), 3% (1/32) for the Shire of Kent (â¼5,600 km2 in the southwest of Western Australia), 1% (1/91) from an approximately 250,000 km2 area across southern Southern Australia and Western Australia, and 0% (0/35) from Mount Mary (â¼150 km2 in the Mid North of South Australia). Neither of the two PCR-positive shingleback skinks had overt signs of upper respiratory tract disease. These results are consistent with serpentoviruses occurring at a relatively low crude prevalence of 1.4% (95% confidence interval, 0.2-4.9%) across these areas, although the potential bias from sampling active and apparently healthy individuals may mean that this estimate is lower than the true prevalence. This contrasts with the high proportion of PCR positives reported in captive individuals. In the absence of experimental or observational data on viral clearance and recovery, Tiliqua spp. skinks that are intended for release into the wild should be housed with strict biosecurity to prevent interactions with captive individuals and screened to ensure that they are not PCR positive before release.
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Antimicrobial resistance (AMR) has emerged as a critical global health challenge. However, the significance of AMR is not limited to humans and domestic animals but extends to wildlife and the environment. Based on the analysis of > 200 peer-reviewed papers, this review provides comprehensive and current insights into the detection of clinically significant antimicrobial resistant bacteria and resistance genes in wild mammals, birds and reptiles worldwide. The review also examines the overlooked roles of wildlife in AMR emergence and transmission. In wildlife, AMR is potentially driven by anthropogenic activity, agricultural and environmental factors, and natural evolution. This review highlights the significance of AMR surveillance in wildlife, identifies species and geographical foci and gaps, and demonstrates the value of multifaceted One Health strategies if further escalation of AMR globally is to be curtailed.
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Contact between humans and wildlife presents a risk for both zoonotic and anthropozoonotic disease transmission. In this study we report the detection of human strains of Mycobacterium tuberculosis in sun bears and an Asiatic black bear in a wildlife rescue centre in Cambodia, confirming for the first time the susceptibility of these bear species to tuberculosis when in close contact with humans. After genotyping revealed two different strains of M. tuberculosis from cases occurring between 2009 and 2019, 100 isolates from 30 sun bear cases, a single Asiatic black bear case, and a human case were subjected to whole genome sequencing. We combined single nucleotide polymorphism analysis and exploration of mixed base calls with epidemiological data to indicate the evolution of each outbreak. Our results confirmed two concurrent yet separate tuberculosis outbreaks and established a likely transmission route in one outbreak where the human case acted as an intermediatory between bear cases. In both outbreaks, we observed high rates of transmission and progression to active disease, suggesting that sun bears are highly susceptible to tuberculosis if exposed under these conditions. Overall, our findings highlight the risk of bi-directional transmission of tuberculosis between humans and captive bears in high human tuberculosis burden regions, with implied considerations for veterinary and public health. We also demonstrate the use of standard genomic approaches to better understand disease outbreaks in captive wildlife settings and to inform control and prevention measures.
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Tuberculosis , Ursidae , Animales , Humanos , Ursidae/genética , Cambodia/epidemiología , Brotes de Enfermedades , Tuberculosis/epidemiología , Tuberculosis/veterinaria , GenómicaRESUMEN
Social risk assessments and case studies of labour conditions in food production primarily focus on specific subpopulations, regions and commodities. To date, research has not systematically assessed labour conditions against international standards across diverse, complex food products. Here we combine data on production, trade, labour intensity and qualitative risk coding to quantitatively assess the risk of forced labour embedded in the US land-based food supply, building on our previous assessment of fruits and vegetables. We demonstrate that animal-based proteins, processed fruits and vegetables, and discretionary foods are major contributors to forced labour risk and that 62% of total forced labour risk stems from domestic production or processing. Our findings reveal the widespread risk of forced labour present in the US food supply and the necessity of collaborative action across all countries-high, middle and low income-to eliminate reliance on labour exploitation.
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Frutas , Trabajo de Parto , Animales , Femenino , Embarazo , Pobreza , Medición de Riesgo , Problemas Sociales , VerdurasRESUMEN
A probe-hybridization quantitative polymerase chain reaction assay specific for Cryptosporidium serpentis (qPCR) has been developed and shown to be extremely sensitive in the laboratory, but clinical sensitivity and specificity for this test are lacking. To approximate the sensitivity and specificity of the C. serpentis qPCR, the medical records from a captive snake colony were reviewed, and between November 2015 and June 2021, 63 eastern indigo snakes (Drymarchon couperi) were necropsied. Of these 63 snakes, 11 had qPCR performed on gastric biopsies collected at the time of necropsy, 8 had qPCR performed on samples collected by gastric swab within 35 days of necropsy, and 34 had qPCR performed on samples collected by cloacal swab within 84 days of necropsy. The qPCR results were then compared to the post-mortem histological findings, where all three sampling techniques had a 100% specificity. The sensitivity was highest in samples collected at necropsy (100%, CI: 63.06 - 100%) followed by the ante-mortem testing: gastric swab (87.50%, CI: 42.13 - 99.64%) and cloacal swab (66.67%, CI: 44.68 - 84.37%).
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Colubridae , Criptosporidiosis , Cryptosporidium , Animales , Humanos , Cryptosporidium/genética , Serpientes , Reacción en Cadena en Tiempo Real de la Polimerasa , EstómagoRESUMEN
Bats have been implicated as the reservoir hosts of filoviruses in Africa, with serological evidence of filoviruses in various bat species identified in other countries. Here, serum samples from 190 bats, comprising 12 different species, collected in Australia were evaluated for filovirus antibodies. An in-house indirect microsphere assay to detect antibodies that cross-react with Ebola virus (Zaire ebolavirus; EBOV) nucleoprotein (NP) followed by an immunofluorescence assay (IFA) were used to confirm immunoreactivity to EBOV and Reston virus (Reston ebolavirus; RESTV). We found 27 of 102 Yinpterochiroptera and 19 of 88 Yangochiroptera samples were positive to EBOV NP in the microsphere assay. Further testing of these NP positive samples by IFA revealed nine bat sera that showed binding to ebolavirus-infected cells. This is the first report of filovirus-reactive antibodies detected in Australian bat species and suggests that novel filoviruses may be circulating in Australian bats.
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Quirópteros , Ebolavirus , Fiebre Hemorrágica Ebola , Animales , Anticuerpos Antivirales , Australia , Fiebre Hemorrágica Ebola/veterinaria , NucleoproteínasRESUMEN
The emergence of SARS-CoV-2 and the subsequent COVID-19 pandemic has resulted in significant global impact. However, COVID-19 is just one of several high-impact infectious diseases that emerged from wildlife and are linked to the human relationship with nature. The rate of emergence of new zoonoses (diseases of animal origin) is increasing, driven by human-induced environmental changes that threaten biodiversity on a global scale. This increase is directly linked to environmental drivers including biodiversity loss, climate change and unsustainable resource extraction. Australia is a biodiversity hotspot and is subject to sustained and significant environmental change, increasing the risk of it being a location for pandemic origin. Moreover, the global integration of markets means that consumption trends in Australia contributes to the risk of disease spill-over in our regional neighbours in Asia-Pacific, and beyond. Despite the clear causal link between anthropogenic pressures on the environment and increasing pandemic risks, Australia's response to the COVID-19 pandemic, like most of the world, has centred largely on public health strategies, with a clear focus on reactive management. Yet, the span of expertise and evidence relevant to the governance of pandemic risk management is much wider than public health and epidemiology. It involves animal/wildlife health, biosecurity, conservation sciences, social sciences, behavioural psychology, law, policy and economic analyses to name just a few.The authors are a team of multidisciplinary practitioners and researchers who have worked together to analyse, synthesise, and harmonise the links between pandemic risk management approaches and issues in different disciplines to provide a holistic overview of current practice, and conclude the need for reform in Australia. We discuss the adoption of a comprehensive and interdisciplinary 'One Health' approach to pandemic risk management in Australia. A key goal of the One Health approach is to be proactive in countering threats of emerging infectious diseases and zoonoses through a recognition of the interdependence between human, animal, and environmental health. Developing ways to implement a One Health approach to pandemic prevention would not only reduce the risk of future pandemics emerging in or entering Australia, but also provide a model for prevention strategies around the world.
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COVID-19 , Pandemias , Animales , Australia/epidemiología , COVID-19/epidemiología , COVID-19/prevención & control , Humanos , Pandemias/prevención & control , Gestión de Riesgos , SARS-CoV-2 , Zoonosis/epidemiología , Zoonosis/prevención & controlRESUMEN
Sarcoptic mange, a parasitic skin disease caused by Sarcoptes scabiei, is an emerging conservation threat to some Australian wildlife species. As a zoonotic and multi-host disease, it has the capacity to exploit different hosts, creating management challenges for susceptible wildlife populations that may suffer high rates of morbidity and mortality. Sarcoptic mange was identified in quenda (Isoodon fusciventer) in a peri-urban region of Perth, Western Australia in 2019. By mid-2021, reported cases were distributed across 107ha. This retrospective study reviews the spatiotemporal distribution, clinical signs and risk factors for sarcoptic mange in quenda from a metropolitan region. Preliminary epidemiological parameters for the outbreak are described, including period prevalence of infested individuals, spatiotemporal analyses, clinical signs of mange, and preliminary risk factor analyses. The period prevalence of sarcoptic mange between July 1, 2019 and June 30, 2021 was 26.9% (CI 95%; 21.2, 33.5) with a mortality rate of 39.6%, owing to severity of disease or secondary complications. Sarcoptic mange was detected more frequently in adult quenda than juveniles (OR: 176.8, CI 95%: 10.7, 2930.1), with adult males more affected than adult females (OR: 3.5, CI 95%: 1.5, 8.4). Clinical signs of disease presented on the rump and tail (100%), followed by the limbs and digits (61.5%). The most common clinical signs recorded were alopecia (92.3%), erythema (46.2%) and open wounds (42.3%). This is the first documented example of a geographically expanding and propagating epizootic of sarcoptic mange in quenda, with implicit welfare and conservation concerns for the species, alongside potential for cases in humans and domestic species that cohabit with or handle quenda in the urban environment. Further, the detection of cases through wildlife rehabilitation centres highlights the critical role such organisations play in conservation and passive surveillance for wildlife diseases of conservation or public and domestic animal health importance.
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Duration of protection from SARS-CoV-2 infection in people living with HIV (PWH) following vaccination is unclear. In a substudy of the phase II/III the COV002 trial (NCT04400838), 54 HIV+ male participants on antiretroviral therapy (undetectable viral loads, CD4+ T cells > 350 cells/µL) received 2 doses of ChAdOx1 nCoV-19 (AZD1222) 4-6 weeks apart and were followed for 6 months. Responses to vaccination were determined by serology (IgG ELISA and Meso Scale Discovery [MSD]), neutralization, ACE-2 inhibition, IFN-γ ELISpot, activation-induced marker (AIM) assay and T cell proliferation. We show that, 6 months after vaccination, the majority of measurable immune responses were greater than prevaccination baseline but with evidence of a decline in both humoral and cell-mediated immunity. There was, however, no significant difference compared with a cohort of HIV-uninfected individuals vaccinated with the same regimen. Responses to the variants of concern were detectable, although they were lower than WT. Preexisting cross-reactive T cell responses to SARS-CoV-2 spike were associated with greater postvaccine immunity and correlated with prior exposure to beta coronaviruses. These data support the ongoing policy to vaccinate PWH against SARS-CoV-2, and they underpin the need for long-term monitoring of responses after vaccination.
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COVID-19 , Infecciones por VIH , COVID-19/prevención & control , ChAdOx1 nCoV-19 , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , SARS-CoV-2 , VacunaciónRESUMEN
OBJECTIVES: To determine the safety of urological admissions and procedures during the height of the COVID-19 pandemic using "hot" and "cold" sites. The secondary objective is to determine risk factors of contracting COVID-19 within our cohort. PATIENTS AND METHODS: A retrospective cohort study of all consecutive patients admitted from March 1 to May 31, 2020 at a high-volume tertiary urology department in London, United Kingdom. Elective surgery was carried out at a "cold" site requiring a negative COVID-19 swab 72-hours prior to admission and patients were required to self-isolate for 14-days preoperatively, while all acute admissions were admitted to the "hot" site.Complications related to COVID-19 were presented as percentages. Risk factors for developing COVID-19 infection were determined using multivariate logistic regression analysis. RESULTS: A total of 611 patients, 451 (73.8%) male and 160 (26.2%) female, with a median age of 57 (interquartile range 44-70) were admitted under the urology team; 101 (16.5%) on the "cold" site and 510 (83.5%) on the "hot" site. Procedures were performed in 495 patients of which eight (1.6%) contracted COVID-19 postoperatively with one (0.2%) postoperative mortality due to COVID-19. Overall, COVID-19 was detected in 20 (3.3%) patients with two (0.3%) deaths. Length of stay was associated with contracting COVID-19 in our cohort (OR 1.25, 95% CI 1.13-1.39). CONCLUSIONS: Continuation of urological procedures using "hot" and "cold" sites throughout the COVID-19 pandemic was safe practice, although the risk of COVID-19 remained and is underlined by a postoperative mortality.
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Sustainable food consumption studies have largely focused on promoting human health within ecological limits. Less attention has been paid to social sustainability, in part because of limited data and models. Globally, agriculture has one of the highest incidences of forced labour, with exploitative conditions enabled by low margins, domestic labour scarcity, inadequate legal protections for workers and high labour requirements. Here we assess the forced labour risk embedded in the US retail supply of fruits and vegetables using distinct datasets and a new forced labour risk scoring method. We demonstrate that there is risk of forced labour in a broad set of fruit and vegetable commodities, with a small number of commodities accounting for a substantial fraction of total risk at the retail supply level. These findings signal potential trade-offs and synergies across dimensions of food system sustainability and the need for novel research approaches to develop evidence-based forced labour risk mitigation strategies.
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This study investigates the occurrence of erythematous lip lesions in a captive sun bear population in Cambodia, including the progression of cheilitis to squamous cell carcinoma, and the presence of Ursid gammaherpesvirus 1. Visual assessment conducted in 2015 and 2016 recorded the prevalence and severity of lesions. Opportunistic sampling for disease testing was conducted on a subset of 39 sun bears, with histopathological examination of lip and tongue biopsies and PCR testing of oral swabs and tissue biopsies collected during health examinations. Lip lesions were similarly prevalent in 2015 (66.0%) and 2016 (68.3%). Degradation of lip lesion severity was seen between 2015 and 2016, and the odds of having lip lesions, having more severe lip lesions, and having lip lesion degradation over time, all increased with age. Cheilitis was found in all lip lesion biopsies, with histological confirmation of squamous cell carcinoma in 64.5% of cases. Single biopsies frequently showed progression from dysplasia to neoplasia. Eighteen of 31 sun bears (58.1%) had at least one sample positive for Ursid gammaherpesvirus 1. The virus was detected in sun bears with and without lip lesions, however due to case selection being strongly biased towards those showing lip lesions it was not possible to test for association between Ursid gammaherpesvirus 1 and lip squamous cell carcinoma. Given gammaherpesviruses can play a role in cancer development under certain conditions in other species, we believe further investigation into Ursid gammaherpesvirus 1 as one of a number of possible co-factors in the progression of lip lesions to squamous cell carcinoma is warranted. This study highlights the progressively neoplastic nature of this lip lesion syndrome in sun bears which has consequences for captive and re-release management. Similarly, the detection of Ursid gammaherpesvirus 1 should be considered in pre-release risk analyses, at least until data is available on the prevalence of the virus in wild sun bears.
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Enfermedades de los Labios/veterinaria , Labio/patología , Ursidae , Animales , Cambodia/epidemiología , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/veterinaria , Progresión de la Enfermedad , Eritema/epidemiología , Eritema/patología , Eritema/veterinaria , Femenino , Gammaherpesvirinae/clasificación , Gammaherpesvirinae/genética , Gammaherpesvirinae/aislamiento & purificación , Enfermedades de los Labios/epidemiología , Enfermedades de los Labios/patología , Neoplasias de los Labios/epidemiología , Neoplasias de los Labios/patología , Neoplasias de los Labios/veterinaria , Masculino , Filogenia , Prevalencia , Factores de Riesgo , Ursidae/virologíaRESUMEN
Macropod Progressive Periodontal Disease (MPPD) is a well-recognised disease that causes high morbidity and mortality in captive macropods worldwide. Epidemiological data on MMPD are limited, although multiple risk factors associated with a captive environment appear to contribute to the development of clinical disease. The identification of risk factors associated with MPPD would assist with the development of preventive management strategies, potentially reducing mortality. Veterinary and husbandry records from eight institutions across Australia and Europe were analysed in a retrospective cohort study (1995 to 2016), examining risk factors for the development of MPPD. A review of records for 2759 macropods found incidence rates (IR) and risk of infection differed between geographic regions and individual institutions. The risk of developing MPPD increased with age, particularly for macropods >10 years (Australia Incidence Rate Ratio (IRR) 7.63, p < 0.001; Europe IRR 7.38, p < 0.001). Prognosis was typically poor, with 62.5% mortality reported for Australian and European regions combined. Practical recommendations to reduce disease risk have been developed, which will assist zoos in providing optimal long-term health management for captive macropods and, subsequently, have a positive impact on both the welfare and conservation of macropods housed in zoos globally.
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Trypanosomes are blood-borne parasites that can infect a variety of different vertebrates, including animals and humans. This study aims to broaden scientific knowledge about the presence and biodiversity of trypanosomes in Australian bats. Molecular and morphological analysis was performed on 86 blood samples collected from seven different species of microbats in Western Australia. Phylogenetic analysis on 18S rDNA and glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) sequences identified Trypanosoma dionisii in five different Australian native species of microbats; Chalinolobus gouldii, Chalinolobus morio, Nyctophilus geoffroyi, Nyctophilus major and Scotorepens balstoni. In addition, two novels, genetically distinct T. dionisii genotypes were detected and named T. dionisii genotype Aus 1 and T. dionisii genotype Aus 2. Genotype Aus 2 was the most prevalent and infected 20.9% (18/86) of bats in the present study, while genotype Aus 1 was less prevalent and was identified in 5.8% (5/86) of Australian bats. Morphological analysis was conducted on trypomastigotes identified in blood films, with morphological parameters consistent with trypanosome species in the subgenus Schizotrypanum. This is the first report of T. dionisii in Australia and in Australian native bats, which further contributes to the global distribution of this cosmopolitan bat trypanosome.
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Quirópteros , Trypanosoma/aislamiento & purificación , Tripanosomiasis/veterinaria , Animales , Gliceraldehído-3-Fosfato Deshidrogenasas/análisis , Microcuerpos/química , Prevalencia , Proteínas Protozoarias/análisis , ARN Protozoario/análisis , ARN Ribosómico 18S/análisis , Trypanosoma/enzimología , Trypanosoma/genética , Tripanosomiasis/epidemiología , Australia Occidental/epidemiologíaRESUMEN
RATIONALE: Low-molecular-weight amines are encountered in pharmaceutical analysis, e.g. as reactants in chemical syntheses, but are challenging to analyse using ultrahigh-performance liquid chromatography/mass spectrometry (UHPLC/MS) due to their high polarity causing poor retention. Ion chromatography/mass spectrometry (IC/MS) is an emerging technique for polar molecule analysis that offers better separation. A generic IC/MS method would overcome problems associated with using UHPLC/MS in drug discovery and development environments. METHODS: Amine standards were analysed using IC/MS with gradient elution (variety of column temperatures evaluated). An electrospray ionisation (ESI) quadrupole mass spectrometer was operated in positive ion polarity in scanning mode. The make-up flow composition was evaluated by assessing the performance of a range of organic modifiers (acetonitrile, ethanol, methanol) and additives (acetic acid, formic acid, methanesulfonic acid). The ESI conditions were optimised to minimise adduct formation and promote generation of protonated molecules. RESULTS: The performance attributes were investigated and optimised for low-molecular-weight amine analysis. Organic solvents and acidic additives were evaluated as make-up flow components to promote ESI, with 0.05% acetic acid in ethanol optimal for producing protonated molecules. The hydrogen bonding capability of amines led to abundant protonated molecule-solvent complexes; optimisation of source conditions reduced these, with collision-induced dissociation voltage having a strong effect. The detection limit was ≤1.78 ng for the amines analysed, which is fit-for-purpose for an open-access chemistry environment. CONCLUSIONS: This study demonstrates the value of IC/MS for analysing low-molecular-weight amines. Good chromatographic separation of mixtures was possible without derivatisation. Ionisation efficiency was greatest using a make-up flow of 0.05% acetic acid in ethanol, and optimisation of ESI source conditions promoted protonated molecule generation for easy determination of molecular weight.
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Aminas , Cromatografía por Intercambio Iónico/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Aminas/análisis , Aminas/química , Desarrollo de Medicamentos , Descubrimiento de Drogas , Peso Molecular , Solventes/químicaRESUMEN
Elephant endotheliotropic herpesvirus (EEHV) infection is a conservation threat to the endangered Asian elephant (Elephas maximus), causing fatal hemorrhagic disease in juvenile elephants throughout the world, including Thailand. This study revealed a subclinical EEHV1 infection rate of 5.5% in healthy captive Asian elephants in Thailand (n = 362). The virus was detected in all age classes above one year old, in both sexes, and across the country - even in facilities with no history of hemorrhagic disease (EEHV HD). Subclinical EEHV infection in Thailand urgently requires proper health management.
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Elefantes/virología , Infecciones por Herpesviridae/veterinaria , Infecciones por Herpesviridae/virología , Herpesviridae/patogenicidad , Animales , Femenino , Masculino , TailandiaRESUMEN
Bats are known reservoirs of a wide variety of viruses that rarely result in overt clinical disease in the bat host. However, anthropogenic influences on the landscape and climate can change species assemblages and interactions, as well as undermine host-resilience. The cumulative result is a disturbance of bat-pathogen dynamics, which facilitate spillover events to sympatric species, and may threaten bat communities already facing synergistic stressors through ecological change. Therefore, characterisation of viral pathogens in bat communities provides important basal information to monitor and predict the emergence of diseases relevant to conservation and public health. This study used targeted molecular techniques, serological assays and next generation sequencing to characterise adenoviruses, coronaviruses and paramyxoviruses from 11 species of insectivorous bats within the South West Botanical Province of Western Australia. Phylogenetic analysis indicated complex ecological interactions including virus-host associations, cross-species infections, and multiple viral strains circulating concurrently within selected bat populations. Additionally, we describe the entire coding sequences for five alphacoronaviruses (representing four putative new species), and one novel adenovirus. Results indicate that viral burden (both prevalence and richness) is not homogeneous among species, with Chalinolobus gouldii identified as a key epidemiological element within the studied communities.
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Biodiversidad , Quirópteros/virología , Adenoviridae/clasificación , Adenoviridae/genética , Adenoviridae/inmunología , Adenoviridae/aislamiento & purificación , Animales , Quirópteros/clasificación , Coronavirus/clasificación , Coronavirus/genética , Coronavirus/inmunología , Coronavirus/aislamiento & purificación , Heces/virología , Conducta Alimentaria , Genoma Viral/genética , Paramyxovirinae/clasificación , Paramyxovirinae/genética , Paramyxovirinae/inmunología , Paramyxovirinae/aislamiento & purificación , Filogenia , Análisis de Secuencia , Estudios Seroepidemiológicos , Especificidad de la Especie , Proteínas Virales/genética , Proteínas Virales/inmunología , Australia Occidental/epidemiologíaRESUMEN
Small organic acids are widely used within the pharmaceutical industry but can be difficult to analyse. Ion chromatography is a suitable technique for the analysis of these acids but method development can be hindered as mass spectrometry is not often used as a detector; this means that peak tracking and peak purity cannot be performed. The authors report method development for the analysis of 2-butynoic acid, where by using electrospray ionisation mass spectrometry, peak purity was investigated and the presence of co-eluting impurities determined. Optimisation of the additives in the make-up flow to the mass spectrometer was shown to have an impact on the response observed. A standard series of organic acids were analysed spiked in to 2-butynoic acid at levels representative of impurities, the presence of the 2-butynoic acid did not impact the linearity or limit of detection observed for the acids; R2 values greater than 0.98 were obtained for all acids with and without the presence of 2-butynoic acid with a limit of detection at 1 ppb for all but one of the acids.
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Técnicas de Química Analítica/métodos , Cromatografía , Ácidos Grasos Insaturados/análisis , Espectrometría de Masa por Ionización de Electrospray , Compuestos Orgánicos/análisisRESUMEN
Australian bat lyssavirus (ABLV) is a known causative agent of neurological disease in bats, humans and horses. It has been isolated from four species of pteropid bats and a single microbat species (Saccolaimus flaviventris). To date, ABLV surveillance has primarily been passive, with active surveillance concentrating on eastern and northern Australian bat populations. As a result, there is scant regional ABLV information for large areas of the country. To better inform the local public health risks associated with human-bat interactions, this study describes the lyssavirus prevalence in microbat communities in the South West Botanical Province of Western Australia. We used targeted real-time PCR assays to detect viral RNA shedding in 839 oral swabs representing 12 species of microbats, which were sampled over two consecutive summers spanning 2016â»2018. Additionally, we tested 649 serum samples via Luminex® assay for reactivity to lyssavirus antigens. Active lyssavirus infection was not detected in any of the samples. Lyssavirus antibodies were detected in 19 individuals across six species, with a crude prevalence of 2.9% (95% CI: 1.8â»4.5%) over the two years. In addition, we present the first records of lyssavirus exposure in two Nyctophilus species, and Falsistrellus mackenziei.
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BACKGROUND: Parasites can exert selection pressure on their hosts through effects on survival, on reproductive success, on sexually selected ornament, with important ecological and evolutionary consequences, such as changes in population viability. Consequently, hemoparasites have become the focus of recent avian studies. Infection varies significantly among taxa. Various factors might explain the differences in infection among taxa, including habitat, climate, host density, the presence of vectors, life history and immune defence. Feeding behaviour can also be relevant both through increased exposure to vectors and consumption of secondary metabolites with preventative or therapeutic effects that can reduce parasite load. However, the latter has been little investigated. Psittaciformes (parrots and cockatoos) are a good model to investigate these topics, as they are known to use biological control against ectoparasites and to feed on toxic food. We investigated the presence of avian malaria parasites (Plasmodium), intracellular haemosporidians (Haemoproteus, Leucocytozoon), unicellular flagellate protozoans (Trypanosoma) and microfilariae in 19 Psittaciformes species from a range of habitats in the Indo-Malayan, Australasian and Neotropical regions. We gathered additional data on hemoparasites in wild Psittaciformes from the literature. We considered factors that may control the presence of hemoparasites in the Psittaciformes, compiling information on diet, habitat, and climate. Furthermore, we investigated the role of diet in providing antiparasitic secondary metabolites that could be used as self-medication to reduce parasite load. RESULTS: We found hemoparasites in only two of 19 species sampled. Among them, all species that consume at least one food item known for its secondary metabolites with antimalarial, trypanocidal or general antiparasitic properties, were free from hemoparasites. In contrast, the infected parrots do not consume food items with antimalarial or even general antiparasitic properties. We found that the two infected species in this study consumed omnivorous diets. When we combined our data with data from studies previously investigating blood parasites in wild parrots, the positive relationship between omnivorous diets and hemoparasite infestation was confirmed. Individuals from open habitats were less infected than those from forests. CONCLUSIONS: The consumption of food items known for their secondary metabolites with antimalarial, trypanocidal or general antiparasitic properties, as well as the higher proportion of infected species among omnivorous parrots, could explain the low prevalence of hemoparasites reported in many vertebrates.