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1.
BackgroundAnthrax, a global re-emerging zoonotic disease in recent years is enzootic in mainland China. Despite its significance to the public health, spatiotemporal distributions of the disease in human and livestock and its potential driving factors remain poorly understood.Conclusions/SignificanceAnthrax in China was characterized by significant seasonality and spatial clustering. The spatial distribution of human anthrax was largely driven by livestock husbandry, human density, land cover, elevation, topsoil features and climate. Enhanced surveillance and intervention for livestock and human anthrax in the high-risk regions, particularly on the Qinghai-Tibetan Plateau, is the key to the prevention of human infections.  相似文献   

2.
Anthrax, caused by the spore-forming bacterium Bacillus anthracis, is a zoonosis affecting animals and humans globally. In the United States, anthrax outbreaks occur in wildlife and livestock, with frequent outbreaks in native and exotic wildlife species in Texas, livestock outbreaks in the Dakotas, and sporadic mixed outbreaks in Montana. Understanding where pathogen and host habitat selection overlap is essential for anthrax management. Resource selection and habitat use of ungulates may be sex-specific and lead to differential anthrax exposure risks across the landscape for males and females. We evaluated female elk (Cervus canadensis) resource selection in the same study areas as male elk in a previous anthrax risk study to identify risk of anthrax transmission to females and compare transmission risk between females and males. We developed a generalized linear mixed-effect model to estimate resource selection for female elk in southwest Montana during the June to August anthrax transmission risk period. We then predicted habitat selection of female and male elk across the study area and compared selection with the distribution of anthrax risk to identify spatial distributions of potential anthrax exposure for the male and female elk. Female and male elk selected different resources during the anthrax risk period, which resulted in different anthrax exposure areas for females and males. The sex-specific resource selection and habitat use could infer different areas of risk for anthrax transmission, which can improve anthrax and wildlife management and have important public health and economic implications. © 2020 The Wildlife Society.  相似文献   

3.
BackgroundAnthrax is a disease that affects humans and animals. In Ethiopia, anthrax is a reportable disease and assumed to be endemic, although laboratory confirmation has not been routinely performed until recently. We describe the findings from the investigation of two outbreaks in Amhara region.MethodsFollowing reports of suspected outbreaks in Wag Hamra zone (Outbreak 1) and South Gondar zone (Outbreak 2), multi-sectoral teams involving both animal and public health officials were deployed to investigate and establish control programs. A suspect case was defined as: sudden death with rapid bloating or bleeding from orifice(s) with unclotted blood (animals); and signs compatible with cutaneous, ingestion, or inhalation anthrax ≤7 days after exposure to a suspect animal (humans). Suspect human cases were interviewed using a standard questionnaire. Samples were collected from humans with suspected anthrax (Outbreak 1 and Outbreak 2) as well as dried meat of suspect animal cases (Outbreak 2). A case was confirmed if a positive test was returned using real-time polymerase chain reaction (qPCR).ResultsIn Outbreak 1, a total of 49 cows died due to suspected anthrax and 22 humans developed symptoms consistent with cutaneous anthrax (40% attack rate), two of whom died due to suspected ingestion anthrax. Three people were confirmed to have anthrax by qPCR. In Outbreak 2, anthrax was suspected to have caused the deaths of two livestock animals and one human. Subsequent investigation revealed 18 suspected cases of cutaneous anthrax in humans (27% attack rate). None of the 12 human samples collected tested positive, however, a swab taken from the dried meat of one animal case (goat) was positive by qPCR.ConclusionWe report the first qPCR-confirmed outbreaks of anthrax in Ethiopia. Both outbreaks were controlled through active case finding, carcass management, ring vaccination of livestock, training of health professionals and outreach with livestock owners. Human and animal health authorities should work together using a One Health approach to improve case reporting and vaccine coverage.  相似文献   

4.
An anthrax outbreak occurred in the Wamba area of southern Samburu, Kenya, between December 2005 and March 2006. The outbreak affected equids including the endangered Grevy's zebras (Equus grevyi), plain zebras (Equis Burchelli) and donkeys (Equus asinus). Most of the deaths were localized in Nkaroni area just west of Wamba town. The diagnosis of anthrax was rapidly confirmed by bacteriological methods. The relevant government departments, including the Kenya Wildlife Service and Veterinary Department, and other stakeholders were promptly informed. Fifty‐three Grevy's zebra and 26 plains zebras died from anthrax. An equal number (eighteen) of adult male and female Grevy's zebras succumbed to the disease. The outbreak affected immature and mature individuals equally. The dead plain zebras included fifteen adult females, two adult males and nine immature individuals. The Veterinary Department responded by vaccinating livestock while Kenya Wildlife Service vaccinated 620 Grevy's zebras within southern Samburu. Examination of sites at which carcasses of animals which succumbed to the disease were burnt, revealed that unsupervised burning did not eliminate anthrax spores in 42% of the cases (n = 14). There is an urgent need to incorporate strategic wildlife disease monitoring in the struggle to save Grevy's zebras and other endangered species.  相似文献   

5.
Infectious diseases that affect wildlife and livestock are challenging to manage and can lead to large-scale die-offs, economic losses, and threats to human health. The management of infectious diseases in wildlife and livestock is made easier with knowledge of disease risk across space and identifying stakeholders associated with high-risk landscapes. This study focuses on anthrax, caused by the bacterium Bacillus anthracis, risk to wildlife and livestock in Montana. There is a history of anthrax in Montana, but the spatial extent of disease risk and subsequent wildlife species at risk are not known. Our objective was to predict the potential geographic distribution of anthrax risk across Montana, identify wildlife species at risk and their distributions, and define stakeholders. We used an ecological niche model to predict the potential distribution of anthrax risk. We overlaid susceptible wildlife species distributions and land ownership delineations on our risk map. We found that there was an extensive region across Montana predicted as potential anthrax risk. These potentially risky landscapes overlapped the ranges of all 6 ungulate species considered in the analysis and livestock grazing allotments, and this overlap was on public and private land for all species. Our findings suggest that there is the potential for a multi-species anthrax outbreak on multiple landscapes across Montana. Our potential anthrax risk map can be used to prioritize landscapes for surveillance and for implementing livestock vaccination programs.  相似文献   

6.
Anthrax, caused by the bacterium Bacillus anthracis, is a zoonotic disease that persists throughout much of the world in livestock, wildlife, and secondarily infects humans. This is true across much of Central Asia, and particularly the Steppe region, including Kazakhstan. This study employed the Genetic Algorithm for Rule-set Prediction (GARP) to model the current and future geographic distribution of Bacillus anthracis in Kazakhstan based on the A2 and B2 IPCC SRES climate change scenarios using a 5-variable data set at 55 km2 and 8 km2 and a 6-variable BioClim data set at 8 km2. Future models suggest large areas predicted under current conditions may be reduced by 2050 with the A2 model predicting ∼14–16% loss across the three spatial resolutions. There was greater variability in the B2 models across scenarios predicting ∼15% loss at 55 km2, ∼34% loss at 8 km2, and ∼30% loss with the BioClim variables. Only very small areas of habitat expansion into new areas were predicted by either A2 or B2 in any models. Greater areas of habitat loss are predicted in the southern regions of Kazakhstan by A2 and B2 models, while moderate habitat loss is also predicted in the northern regions by either B2 model at 8 km2. Anthrax disease control relies mainly on livestock vaccination and proper carcass disposal, both of which require adequate surveillance. In many situations, including that of Kazakhstan, vaccine resources are limited, and understanding the geographic distribution of the organism, in tandem with current data on livestock population dynamics, can aid in properly allocating doses. While speculative, contemplating future changes in livestock distributions and B. anthracis spore promoting environments can be useful for establishing future surveillance priorities. This study may also have broader applications to global public health surveillance relating to other diseases in addition to B. anthracis.  相似文献   

7.
BackgroundStatistical models are regularly used in the forecasting and surveillance of infectious diseases to guide public health. Variable selection assists in determining factors associated with disease transmission, however, often overlooked in this process is the evaluation and suitability of the statistical model used in forecasting disease transmission and outbreaks. Here we aim to evaluate several modelling methods to optimise predictive modelling of Ross River virus (RRV) disease notifications and outbreaks in epidemiological important regions of Victoria and Western Australia.Methodology/Principal findingsWe developed several statistical methods using meteorological and RRV surveillance data from July 2000 until June 2018 in Victoria and from July 1991 until June 2018 in Western Australia. Models were developed for 11 Local Government Areas (LGAs) in Victoria and seven LGAs in Western Australia. We found generalised additive models and generalised boosted regression models, and generalised additive models and negative binomial models to be the best fit models when predicting RRV outbreaks and notifications, respectively. No association was found with a model’s ability to predict RRV notifications in LGAs with greater RRV activity, or for outbreak predictions to have a higher accuracy in LGAs with greater RRV notifications. Moreover, we assessed the use of factor analysis to generate independent variables used in predictive modelling. In the majority of LGAs, this method did not result in better model predictive performance.Conclusions/SignificanceWe demonstrate that models which are developed and used for predicting disease notifications may not be suitable for predicting disease outbreaks, or vice versa. Furthermore, poor predictive performance in modelling disease transmissions may be the result of inappropriate model selection methods. Our findings provide approaches and methods to facilitate the selection of the best fit statistical model for predicting mosquito-borne disease notifications and outbreaks used for disease surveillance.  相似文献   

8.
We determined the genotypes of seven Bacillus anthracis strains that were recovered from nine anthrax outbreaks in North-East China from 2010 to 2014, and two approved vaccine strains that are currently in use in China. The causes of these cases were partly due to local farmers being unaware of the presence of anthrax, and butchers with open wounds having direct contact with anthrax-contaminated meat products. The genotype of five of the seven recovered strains was A.Br.001/002 sub-lineage, which was concordant with previously published research. The remaining two cases belongs to the A.Br.Ames sub-lineage. Both of these strains displayed an identical SNR pattern, which was the first time that this genotype was identified in North-East China. Strengthening education in remote villages of rural China is an important activity aimed at fostering attempts to prevent and control anthrax. The genotype of the vaccine strain Anthrax Spore Vaccine No.II was A.Br.008/009 and A.Br.001/002 for the vaccine strain Anthrax Spore Vaccine Non-capsulated. Further studies of their characteristics are clearly warranted.  相似文献   

9.
Aims: To evaluate the potential role of fungal community structure in predisposing Kenyan maize to severe aflatoxin contamination by contrasting aflatoxin‐producing fungi resident in the region with repeated outbreaks of lethal aflatoxicosis to those in regions without a history of aflatoxicosis. Methods and Results: Fungi belonging to Aspergillus section Flavi were isolated from maize samples from three Kenyan provinces between 2004 and 2006. Frequencies of identified strains and aflatoxin‐producing abilities were assessed, and the data were analysed by statistical means. Most aflatoxin‐producing fungi belonged to Aspergillus flavus. The two major morphotypes of A. flavus varied greatly between provinces, with the S strain dominant in both soil and maize within aflatoxicosis outbreak regions and the L strain dominant in nonoutbreak regions. Conclusions: Aspergillus community structure is an important factor in the development of aflatoxins in maize in Kenya and, as such, is a major contributor to the development of aflatoxicosis in the Eastern Province. Significance and Impact of the Study: Since 1982, deaths caused by aflatoxin‐contaminated maize have repeatedly occurred in the Eastern Province of Kenya. The current study characterized an unusual fungal community structure associated with the lethal contamination events. The results will be helpful in developing aflatoxin management practices to prevent future outbreaks in Kenya.  相似文献   

10.
Environmentally transmitted diseases are comparatively poorly understood and managed, and their ecology is particularly understudied. Here we identify challenges of studying environmental transmission and persistence with a six‐sided interdisciplinary review of the biology of anthrax (Bacillus anthracis). Anthrax is a zoonotic disease capable of maintaining infectious spore banks in soil for decades (or even potentially centuries), and the mechanisms of its environmental persistence have been the topic of significant research and controversy. Where anthrax is endemic, it plays an important ecological role, shaping the dynamics of entire herbivore communities. The complex eco‐epidemiology of anthrax, and the mysterious biology of Bacillus anthracis during its environmental stage, have necessitated an interdisciplinary approach to pathogen research. Here, we illustrate different disciplinary perspectives through key advances made by researchers working in Etosha National Park, a long‐term ecological research site in Namibia that has exemplified the complexities of the enzootic process of anthrax over decades of surveillance. In Etosha, the role of scavengers and alternative routes (waterborne transmission and flies) has proved unimportant relative to the long‐term persistence of anthrax spores in soil and their infection of herbivore hosts. Carcass deposition facilitates green‐ups of vegetation to attract herbivores, potentially facilitated by the role of anthrax spores in the rhizosphere. The underlying seasonal pattern of vegetation, and herbivores' immune and behavioural responses to anthrax risk, interact to produce regular ‘anthrax seasons’ that appear to be a stable feature of the Etosha ecosystem. Through the lens of microbiologists, geneticists, immunologists, ecologists, epidemiologists, and clinicians, we discuss how anthrax dynamics are shaped at the smallest scale by population genetics and interactions within the bacterial communities up to the broadest scales of ecosystem structure. We illustrate the benefits and challenges of this interdisciplinary approach to disease ecology, and suggest ways anthrax might offer insights into the biology of other important pathogens. Bacillus anthracis, and the more recently emerged Bacillus cereus biovar anthracis, share key features with other environmentally transmitted pathogens, including several zoonoses and panzootics of special interest for global health and conservation efforts. Understanding the dynamics of anthrax, and developing interdisciplinary research programs that explore environmental persistence, is a critical step forward for understanding these emerging threats.  相似文献   

11.
This study has demonstrated that low numbers of African armyworms (Spodoptera exempta) (Walker) (Lepidoptera: Noctuidae) can be found throughout the year in parts of the coastal and highland regions of Kenya where there is frequent rainfall. During the study period the numbers of moths caught in pheromone traps in these regions built up during the short and long rains, and decreased dramatically during the intervening dry seasons. There was a lag of one to two months between the peaks for rainfall and moth numbers. This contrasts with the situation at sites of the seasonal outbreaks of armyworm larvae, where a sudden preceding influx of moths coincides with the rainfall. A positive correlation was found, for the long rains seasons only, between the number of armyworm outbreaks throughout the country and the peak numbers of moths in coastal and highland regions.It is suggested therefore that the peak numbers of moths trapped in the eastern highlands and coastal regions during the rainy seasons arise principally from outbreaks in the extensive seasonal grasslands. These grassland areas diminish considerably during the prolonged dry periods between the two rainy seasons, and it is only the eastern highland and coastal regions that are likely to provide suitable habitats for breeding during the dry seasons. The significance of these populations for initiating the first outbreaks of the following season is discussed.  相似文献   

12.
Anthrax is a disease of herbivores caused by the gram-positive bacterium Bacillus anthracis. It can affect cattle, sheep, swine, horses and various species of wildlife. The routes for the spread among wildlife are reviewed. There are three kinds of human anthrax – inhalation, cutaneous, and intestinal anthrax – which differ in their routes of infection and outcomes. In the United States, confirmation of cases is made by the isolation of B. anthracis and by biochemical tests. Vaccination is not recommended for the general public; civilians who should be vaccinated include those who, in their work places, come in contact with products potentially contaminated with B. anthracis spores, and people engaged in research or diagnostic activities. After September 11, 2001, there were bioterrorism anthrax attacks in the United States: anthrax-laced letters sent to multiple locations were the source of infectious B. anthracis. The US Postal Service issued recommendations to prevent the danger of hazardous exposure to the bacterium. B. anthracis spores can spread easily and persist for very long times, which makes decontamination of buildings very difficult. Early detection, rapid diagnosis, and well-coordinated public health response are the key to minimizing casualties. The US Government is seeking new ways to deter bioterrorism, including a tighter control of research on infectious agents, even though pathogens such as B. anthracis are widely spread in nature and easy to grow. It is necessary to define the boundary between defensive and offensive biological weapons research. Deterring bioterrorism should not restrict critical scientific research. Electronic Publication  相似文献   

13.
The various human‐induced threats imposed on nature have recently triggered the study of species' distributions. We developed potential suitability models using two algorithms for a threatened African mahogany, Entandrophragma angolense, in three East African countries; Kenya, Tanzania and Uganda. The effect of features selection and modelling algorithm selection on potential suitability predictions was explored. Occurrence records and high‐resolution environmental data were used. The two species distribution modelling techniques were genetic algorithm rule for prediction; and maximum entropy modelling. With Maxent, the area under the receiver characteristic operating curve (AUC) for potential distribution models tested on independent data ranged from 0.942 to 0.972 when using automatic features and from 0.974 to 0.666 with target or specific features. With GARP, AUC for potential distribution models ranged from 0.591 to 0.736 with all rule types and from 0.388 to 0.805 for specific rule types (Tables  1  and 2 ). The area under the E. angolense potential suitability was best predicted by soil, rainfall and aspect using GARP. Potential suitability increased with increasing aspect and decreased with increasing slope. Low rainfall and elevation increased potential suitability, while high levels of either variable decreased potential suitability. Potential suitability maps for vulnerable species require using a multi‐algorithm, fine scale data approach and incorporation of environmental variables like soil, slope, land use and elevation. Species distribution models can offer insight on the distribution requirements of vulnerable species and help guide the development of management plans. Results of this study suggest that E. angolense management plans should promote the protection of terrestrial forests surrounding water bodies including Mabira forest in Uganda.  相似文献   

14.
15.
Anthrax in Russia has for a long time posed a serious problem for public health and veterinary services. At the beginning of the century, 40-60 thousand cases of this infection were annually reported in the country in agricultural animals and about 10-20 thousand cases in people where each fourth (25%) was dying. In the Russian Federation the registration of anthrax foci is obligatory for veterinary as well as for sanitary-epidemiological services. So our initial project, funded by the International Technical and Scientific Center in Moscow, has envisaged the collection of all data of known anthrax foci, including the village name, agricultural council, region, oblast and year of occurrence. The objective is to assemble a reference handbook, "Register of stable anthrax sites in the Russian Federation", containing organized information on more than 10 000 anthrax foci occurring during the past 100 years. Such a study makes it possible to identify regions characterized by the highest concentrations of stationary anthrax sites in Russia, to identify trends in expressed activity of such sites through the periodic emergence of disease in humans and animals, and to determine the factors contributing to the formation of such trends. In doing this, it makes it possible to develop contingency plans for different risk locations (i.e. high risk of persistent infection, high risk of sporadic occurrence, low risk areas, etc.) in terms of anthrax in Russia, to identify high risk areas and develop a differentiated strategy of vaccination and other control strategies, and to develop preventive recommendations to reduce risk in high risk areas. It is now important to develop the second step of the project: to develop in depth studies of particular clusters to determine which factors are associated with Russian anthrax outbreaks. Maps will greatly enhance the value of this work in terms of spatial analysis. Furthermore, this supplementary project will allow the incorporation of powerful Geographic Information System (GIS) electronic mapping technology so that natural geographic features, such as soil type, climate, etc., can be compared with anthrax distributions in Russia using standard GIS and statistical analysis. At the present time, it is imperative to develop a detailed understanding of the world's distribution of anthrax and what geographic factors determine its prevalence.  相似文献   

16.
Anthrax is the archetype zoonosis; no other infectious disease affects such a wide range of species, including humans, although most susceptible are herbivorous mammals. Although the disease appears to have been recognized for centuries, it has yet to be established scientifically how animals contract it. While primarily a disease of warmer regions, it has long been spread to cooler zones through the trade of infected animals or contaminated animal products. Today it is still endemic in many countries of Africa and Asia and non-endemic countries must remain alert to the possibility of imports from such endemic areas resulting in outbreaks in their own livestock. The epidemiology of anthrax is becoming understood better with new systems coming on stream for distinguishing different genotypes and this is covered in detail. Clinical signs and pathology in animals are described.  相似文献   

17.
The biological attack conducted through the US postal system in 2001 broadened the threat posed by anthrax from one pertinent mainly to soldiers on the battlefield to one understood to exist throughout our society. The expansion of the threatened population placed greater emphasis on the reexamination of how we vaccinate against Bacillus anthracis. The currently-licensed Anthrax Vaccine, Adsorbed (AVA) and Anthrax Vaccine, Precipitated (AVP) are capable of generating a protective immune response but are hampered by shortcomings that make their widespread use undesirable or infeasible. Efforts to gain US Food and Drug Administration (FDA) approval for licensure of a second generation recombinant protective antigen (rPA)-based anthrax vaccine are ongoing. However, this vaccine’s reliance on the generation of a humoral immune response against a single virulence factor has led a number of scientists to conclude that the vaccine is likely not the final solution to optimal anthrax vaccine design. Other vaccine approaches, which seek a more comprehensive immune response targeted at multiple components of the B. anthracis organism, are under active investigation. This review seeks to summarize work that has been done to build on the current PA-based vaccine methodology and to evaluate the search for future anthrax prophylaxis strategies.  相似文献   

18.

In 2016, an outbreak of anthrax killing thousands of reindeer and affecting dozens of humans occurred on the Yamal peninsula, Northwest Siberia, after 70 years of epidemiological situation without outbreaks. The trigger of the outbreak has been ascribed to the activation of spores due to permafrost thaw that was accelerated during the summer heat wave. The focus of our study is on the dynamics of local environmental factors in connection with the observed anthrax revival. We show that permafrost was thawing rapidly for already 6 years before the outbreak. During 2011–2016, relatively warm years were followed by cold years with a thick snow cover, preventing freezing of the soil. Furthermore, the spread of anthrax was likely intensified by an extremely dry summer of 2016. Concurrent with the long-term decreasing trend in the regional annual precipitation, the rainfall in July 2016 was less than 10% of its 30-year mean value. We conclude that epidemiological situation of anthrax in the previously contaminated Arctic regions requires monitoring of climatic factors such as warming and precipitation extremes.

  相似文献   

19.
Between January and February 1997, there was a severe outbreak of anthrax on 83 properties in north-central Victoria, Australia. Vaccination was used as a major tool to control the outbreak by establishing a vaccination buffer zone 30 km by 20 km. In all, 78, 649 cattle in 457 herds were vaccinated in a three week program. In the face of the outbreak, there was a delay before vaccination was able to stop deaths. In the 10 days following vaccination 144 cases of confirmed anthrax occurred and 38 cases occurred more than 10 days after vaccination. When all cattle on at-risk properties were revaccinated in October and early November 1997, there were only two confirmed cases of anthrax in vaccinated seven and nine month old calves in the following anthrax season. Investigations into the epidemiology of the outbreak were unable to establish a single major association for the spread of the disease by flies, biting insects, carrion scavengers, wind, manufactured feed, milk factory tanker routes, veterinary visits, animal treatments, movements of personnel between farms or burning of carcases. The weather conditions in the outbreak area were part of a long dry spell with periods of high daily and night temperatures, continuing high humidity over the period and higher than normal soil temperatures. It is possible that extensive earth works in the district involving irrigated pasture renovation and water channel and drainage renovation could have disturbed old anthrax graves. It is postulated that these works released spores that were dispersed in the preceding wet winter across poorly drained areas that formed the axis for the outbreak. The earth moving renovations establishing irrigation in the area were conducted in the late 1890s, and before the occurrence of anthrax outbreaks were recorded. The axis of the outbreak was the major stock route for cattle and sheep moving from southern Victoria to northern Victoria and southern New South Wales, and undoubtedly there would have been extensive anthrax outbreaks before vaccine became available in the 1890s. In respect of other outbreaks, the events in Victoria most resembled outbreaks of anthrax recorded in the United States of America in the 1950s, 1960s and 1970s.  相似文献   

20.
The MEK family of protein kinases plays key roles in regulating cellular responses to mitogens as well as environmental stress. Inappropriate activation of these kinases contributes to tumorigenesis. In contrast, anthrax lethal factor, the principal virulence factor of anthrax toxin, has been demonstrated to selectively inactivate MEKs. In this article we will discuss recent advances in our understanding of molecular aspects of the pathogenesis of anthrax, emphasizing the potential role of MEK signalling in this disease, and outline novel strategies to use anthrax lethal toxin in the treatment of cancer.

Key Words

Anthrax, MEK, MAPK, Cancer  相似文献   

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