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Disease Outbreaks (disease + outbreak)
Kinds of Disease Outbreaks Selected AbstractsNodavirus infection of juvenile white seabass, Atractoscion nobilis, cultured in southern California: first record of viral nervous necrosis (VNN) in North AmericaJOURNAL OF FISH DISEASES, Issue 5 2001P A Curtis The viral aetiology of mass mortalities of white seabass, Atractoscion nobilis, cultured in southern California, USA was examined. Disease outbreaks occurred in juvenile fish reared at two culture facilities from June to December 1999, with clinical signs such as anorexia and erratic swimming motion. Microscopic lesions observed in moribund fish included marked vacuolation of brain, spinal cord and retina. The piscine nodavirus (Betanodavirus), the causative agent of viral nervous necrosis (VNN), was detected in the affected tissues by electron microscopy, indirect fluorescent antibody test (IFAT), reverse transcription,polymerase chain reaction (RT,PCR), and isolation in cell culture. The agent was identified as one of the four known genotypes of piscine nodavirus. In addition, a similar nodavirus was also detected in fish samples from disease outbreaks at the same facility in 1992. In the last decade, VNN has been reported among cultured populations of marine fish worldwide and this paper is the first record of the agent in North America. [source] The integration of ecological risk assessment and structured decision making into watershed managementINTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 1 2007Dan W Ohlson Abstract Watershed management processes continue to call for more science and improved decision making that take into account the full range of stakeholder perspectives. Increasingly, the core principles of ecological risk assessment (i.e., the development and use of assessment endpoints and conceptual models, conducting exposure and effects analysis) are being incorporated and adapted in innovative ways to meet the call for more science. Similarly, innovative approaches to adapting decision analysis tools and methods for incorporating stakeholder concerns in complex natural resource management decisions are being increasingly applied. Here, we present an example of the integration of ecological risk assessment with decision analysis in the development of a watershed management plan for the Greater Vancouver Water District in British Columbia, Canada. Assessment endpoints were developed, ecological inventory data were collected, and watershed models were developed to characterize the existing and future condition of 3 watersheds in terms of the potential risks to water quality. Stressors to water quality include sedimentation processes (landslides, streambank erosion) and forest disturbance (wildfire, major insect or disease outbreak). Three landscape-level risk management alternatives were developed to reflect different degrees of management intervention. Each alternative was evaluated under different scenarios and analyzed by explicitly examining value-based trade-offs among water quality, environmental, financial, and social endpoints. The objective of this paper is to demonstrate how the integration of ecological risk assessment and decision analysis approaches can support decision makers in watershed management. [source] Severe acute respiratory syndrome, tourism and the mediaINTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 1 2005Peter Mason Abstract There has been an assumption, based on trends from the last two decades of the twentieth century, that global tourism will continue to grow. A number of events in the early twenty first century, however, have called this into question. Some of these have been natural occurrences, others anthropogenic, such as the terrorist attacks in New York in 2001, which indirectly affected global tourism, and that in Bali in 2002, where tourists were the major target. The outbreak of the disease severe acute respiratory syndrome (SARS) in early 2003 had direct and significant impacts on global tourism. This article provides an overview of the SARS outbreak and its impact on global tourism, and focuses on the role of the media in relation to the disease outbreak. Eighteen months on from the height of the outbreak, SARS appeared to have been checked, but there have a number of subsequent cases and of particular concern, it has been predicted that the disease will return on a large scale, and therefore a future research agenda is also presented. Copyright © 2005 John Wiley & Sons, Ltd. [source] Role of 2,4-Diacetylphloroglucinol-Producing Fluorescent Pseudomonas spp. in the Defense of Plant RootsPLANT BIOLOGY, Issue 1 2007D. M. Weller Abstract: Plants have evolved strategies of stimulating and supporting specific groups of antagonistic microorganisms in the rhizosphere as a defense against diseases caused by soilborne plant pathogens owing to a lack of genetic resistance to some of the most common and widespread soilborne pathogens. Some of the best examples of natural microbial defense of plant roots occur in disease suppressive soils. Soil suppressiveness against many different diseases has been described. Take-all is an important root disease of wheat, and soils become suppressive to take-all when wheat or barley is grown continuously in a field following a disease outbreak; this phenomenon is known as take-all decline (TAD). In Washington State, USA and The Netherlands, TAD results from the enrichment during monoculture of populations of 2,4-diacetylphloroglucinol (2,4-DAPG)-producing Pseudomonas fluorescens to a density of 105 CFU/g of root, the threshold required to suppress the take-all pathogen, Gaeumannomyces graminis var. tritici. 2,4-DAPG-producing P. fluorescens also are enriched by monoculture of other crops such as pea and flax, and evidence is accumulating that 2,4-DAPG producers contribute to the defense of plant roots in many different agroecosystems. At this time, 22 distinct genotypes of 2,4-DAPG producers (designated A - T, PfY and PfZ) have been defined by whole-cell repetitive sequence-based (rep)-PCR analysis, restriction fragment length polymorphism (RFLP) analysis of phlD, and phylogenetic analysis of phlD, but the number of genotypes is expected to increase. The genotype of an isolate is predictive of its rhizosphere competence on wheat and pea. Multiple genotypes often occur in a single soil and the crop species grown modulates the outcome of the competition among these genotypes in the rhizosphere. 2,4-DAPG producers are highly effective biocontrol agents against a variety of plant diseases and ideally suited for serving as vectors for expressing other biocontrol traits in the rhizosphere. [source] Successful intervention in a disease outbreak in the endangered Iberian lynx: what can we learn?ANIMAL CONSERVATION, Issue 3 2009K. A. Alexander No abstract is available for this article. [source] Review of identification and traceability legislation for pigs in AustraliaAUSTRALIAN VETERINARY JOURNAL, Issue 7 2007N Schembri Objective To assess Australia's capability to trace pig movements in the event of an exotic disease outbreak by highlighting the commonalities and inconsistencies between the various state and territory legislations in defining how pig producers are located; their pigs are identified; and whether movement records are required post,farm gate. Procedure A review of the identification and traceability legislation applicable to pigs in Australia was undertaken over a 6 month period. The appropriate legislative Acts and Regulations were downloaded from the Australasian Legal Information Institute internet site (http://www.austlii.edu.au/) and reviewed. Results The Australian pig industry currently uses the branding method (tattooing) to identify pigs for sale or slaughter, with each state responsible for its own pig identification and movement control systems. Areas of concern identified included inconsistencies with the minimum weight or age of pigs that require identification; discrepancies between methods of tattoo registration and shortfalls in documentation for recording pig movements. Conclusion Our findings highlight the flaws in Australia's current state legislative Acts and Regulations for identifying pigs and tracking their movements, which compromise the ability of jurisdictions to meet the endorsed National Performance Standards. Improvements in these areas will enhance security to the pig and other livestock industries in the event of future exotic disease outbreaks. [source] Understanding the Causes of Disease in European Freshwater CrayfishCONSERVATION BIOLOGY, Issue 6 2004BRETT F. EDGERTON Aphanomyces astaci; bioseguridad; epizootia; langostinos de agua dulce; patología de langostinos; peste de langostinos Abstract:,Native European freshwater crayfish (Astacida, Decapoda) are under severe pressure from habitat alteration, the introduction of nonindigenous species, and epizootic disease. Crayfish plague, an acute disease of freshwater crayfish caused by the fungus-like agent Aphanomyces astaci, was introduced into Europe in the mid-nineteenth century and is responsible for ongoing widespread epizootic mortality in native European populations. We reviewed recent developments and current practices in the field of crayfish pathology. The severity of crayfish plague has resulted in an overemphasis on it. Diagnostic methods for detecting fungi and fungal-like agents, and sometimes culturing them, are frequently the sole techniques used to investigate disease outbreaks in European freshwater crayfish. Consequently, the causes of a significant proportion of outbreaks are undetermined. Pathogen groups well known for causing disease in other crustaceans, such as viruses and rickettsia-like organisms, are poorly understood or unknown in European freshwater crayfish. Moreover, the pathogenic significance of some long-known pathogens of European freshwater crayfish remains obscure. For effective management of this culturally significant and threatened resource, there is an urgent need for researchers, diagnosticians, and resource managers to address the issue of disease in European freshwater crayfish from a broader perspective than has been applied previously. Resumen:,Los langostinos nativos de Europa (Astacida, Decapada) están bajo severa presión por alteración del hábitat, la introducción de especies no nativas y una enfermedad epizoótica. La peste de langostinos, una enfermedad aguda de langostinos de agua dulce producida por el agente micoide Aphanomyces astaci, fue introducida a Europa a mediados del siglo diecinueve y es responsable de la actual mortalidad epizoótica de poblaciones Europeas nativas. Revisamos acontecimientos recientes y prácticas actuales en el campo de la patología de langostinos. La severidad de la peste de langostinos ha resultado en un excesivo énfasis en ella. Los métodos para diagnosticar, y algunas veces cultivar, hongos y agentes micoides frecuentemente son la única técnica empleada al investigar brotes de la enfermedad en langostinos de agua dulce en Europa. Consecuentemente, no están determinadas las causas de una proporción significativa de los brotes. Grupos patógenos, como virus y organismos similares a rickettsias, bien conocidos por producir enfermedades en otros crustáceos son poco o nada conocidos en langostinos de agua dulce de Europa. Más aún, el significado patogénico de algunos patógenos de langostinos de agua dulce de Europa largamente conocidos es oscuro. Para el manejo efectivo de este recurso culturalmente significativo y amenazado es urgente la necesidad de investigadores, diagnosticadores y gestores de recursos para atender el asunto de la enfermedad en langostinos de agua dulce europeos desde una perspectiva más amplia que la previamente aplicada. [source] Running to stand still: adaptation and the response of plants to rapid climate changeECOLOGY LETTERS, Issue 9 2005Alistair S. Jump Abstract Climate is a potent selective force in natural populations, yet the importance of adaptation in the response of plant species to past climate change has been questioned. As many species are unlikely to migrate fast enough to track the rapidly changing climate of the future, adaptation must play an increasingly important role in their response. In this paper we review recent work that has documented climate-related genetic diversity within populations or on the microgeographical scale. We then describe studies that have looked at the potential evolutionary responses of plant populations to future climate change. We argue that in fragmented landscapes, rapid climate change has the potential to overwhelm the capacity for adaptation in many plant populations and dramatically alter their genetic composition. The consequences are likely to include unpredictable changes in the presence and abundance of species within communities and a reduction in their ability to resist and recover from further environmental perturbations, such as pest and disease outbreaks and extreme climatic events. Overall, a range-wide increase in extinction risk is likely to result. We call for further research into understanding the causes and consequences of the maintenance and loss of climate-related genetic diversity within populations. [source] Sponge disease: a global threat?ENVIRONMENTAL MICROBIOLOGY, Issue 6 2007Nicole S. Webster Summary Sponges are the most simple and primitive metazoans, yet they have various biological and ecological properties that make them an influential component of coral-reef ecosystems. Marine sponges provide refuge for many small invertebrates and are critical to benthic-pelagic coupling across a wide range of habitats. Reports of sponge disease have increased dramatically in recent years with sponge populations decimated throughout the Mediterranean and Caribbean. Reports also suggest an increased prevalence of sponge disease in Papua New Guinea, the Great Barrier Reef and in the reefs of Cozumel, Mexico. These epidemics can have severe impacts on the survival of sponge populations, the ecology of the reef and the fate of associated marine invertebrates. Despite the ecological and commercial importance of sponges, the understanding of sponge disease is limited. There has generally been a failure to isolate and identify the causative agents of sponge disease, with only one case confirming Koch's postulates and identifying a novel Alphaproteobacteria strain as the primary pathogen. Other potential disease agents include fungi, viruses, cyanobacteria and bacterial strains within the Bacillus and Pseudomonas genera. There is some evidence for correlations between sponge disease and environmental factors such as climate change and urban/agricultural runoff. This review summarizes the occurrence of sponge disease, describes the syndromes identified thus far, explores potential linkages with environmental change and proposes a strategy for future research towards better management of sponge disease outbreaks. [source] Crystal structures of Nipah and Hendra virus fusion core proteinsFEBS JOURNAL, Issue 19 2006Zhiyong Lou The Nipah and Hendra viruses are highly pathogenic paramyxoviruses that recently emerged from flying foxes to cause serious disease outbreaks in humans and livestock in Australia, Malaysia, Singapore and Bangladesh. Their unique genetic constitution, high virulence and wide host range set them apart from other paramyxoviruses. These characteristics have led to their classification into the new genus Henpavirus within the family Paramyxoviridae and to their designation as Biosafety Level 4 pathogens. The fusion protein, an enveloped glycoprotein essential for viral entry, belongs to the family of class I fusion proteins and is characterized by the presence of two heptad repeat (HR) regions, HR1 and HR2. These two regions associate to form a fusion-active hairpin conformation that juxtaposes the viral and cellular membranes to facilitate membrane fusion and enable subsequent viral entry. The Hendra and Nipah virus fusion core proteins were crystallized and their structures determined to 2.2 Å resolution. The Nipah and Hendra fusion core structures are six-helix bundles with three HR2 helices packed against the hydrophobic grooves on the surface of a central coiled coil formed by three parallel HR1 helices in an oblique antiparallel manner. Because of the high level of conservation in core regions, it is proposed that the Nipah and Hendra virus fusion cores can provide a model for membrane fusion in all paramyxoviruses. The relatively deep grooves on the surface of the central coiled coil represent a good target site for drug discovery strategies aimed at inhibiting viral entry by blocking hairpin formation. [source] Analysis of bacterial foodborne disease outbreaks in China between 1994 and 2005FEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2007Shijie Wang Abstract To gain an understanding of the outbreaks of bacterial foodborne diseases and the subsequent health impact, we reviewed 2447 papers from journals published in China that reported 1082 bacterial foodborne disease cases occurring between 1994 and 2005. Among the 1082 outbreaks of bacterial foodborne disease for which the etiology was determined, Vibrio parahaemolyticus caused the most outbreaks, followed by Salmonella, and Clostridium botulinum led to the most deaths. Most of the outbreaks occurred between May and October, except for Clostridium botulinum, which mainly occurred in January and February. In littoral provinces, Vibrio parahaemolyticus caused the most events, whereas in inland provinces, the largest percentage of events was caused by Salmonella. This review provides a background and analysis of Chinese foodborne disease caused by bacteria. We hope that this review can be compared to reviews from other regions of the world, in an attempt to prevent future outbreaks from occurring. [source] Molecular typing of meningococci: recommendations for target choice and nomenclatureFEMS MICROBIOLOGY REVIEWS, Issue 1 2007Keith A. Jolley Abstract The diversity and dynamics of Neisseria meningitidis populations generate a requirement for high resolution, comprehensive, and portable typing schemes for meningococcal disease surveillance. Molecular approaches, specifically DNA amplification and sequencing, are the methods of choice for various reasons, including: their generic nature and portability, comprehensive coverage, and ready implementation to culture negative clinical specimens. The following target genes are recommended: (1) the variable regions of the antigen-encoding genes porA and fetA and, if additional resolution is required, the porB gene for rapid investigation of disease outbreaks and investigating the distribution of antigenic variants; (2) the seven multilocus sequence typing loci,these data are essential for the most effective national, and international management of meningococcal disease, as well as being invaluable in studies of meningococcal population biology and evolution. These targets have been employed extensively in reference laboratories throughout the world and validated protocols have been published. It is further recommended that a modified nomenclature be adopted of the form: serogroup: PorA type: FetA type: sequence type (clonal complex), thus: B: P1.19,15: F5-1: ST-33 (cc32). [source] Survival of human enteric viruses in the environment and foodFEMS MICROBIOLOGY REVIEWS, Issue 4 2004Artur Rze Abstract Human enteric pathogenic viruses can enter the environment through discharge of waste materials from infected persons, and be transmitted back to susceptible persons to continue the cycle of disease. Contamination of food with viruses may also promote disease outbreaks. A number of studies have investigated the survival characteristics of several enteric viruses in various environments and foodstuffs, to help explain the transmissibility of these pathogens. This review deals with published work on enteric virus survival on fomites, and in waters, soil, and foods; the results of these studies have illustrated the robust survival of viruses in these environments. Much information is lacking, however, especially for foodstuffs and soils, and no detailed information is available concerning the survival of noroviruses, the most significant foodborne type. [source] PLAGUE AND POWER RELATIONSGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 4 2007Rodrick Wallace ABSTRACT Public policy and economic practice, quintessential expressions of institutional cognition, create an opportunity structure constituting a tunable, highly patterned,,non-white noise' in a generalized epidemiological stochastic resonance that can efficiently amplify unhealthy living and working conditions, particularly within highly concentrated, marginalized urban populations, to evoke infectious disease outbreaks. This is especially true for the infections carried by socially generated ,risk behaviours' which are usually adaptations to histories of resource deprivation or marginalization. A number of local epidemics originating in such ecological keystone communities may subsequently undergo a policy and structure-driven phase transition to become a coherent pandemic, a spreading plague which can entrain more affluent populations into the disease ecology of marginalization. We use this approach to contrast the ecological resilience of apartheid and egalitarian social systems, and apply these perspectives to the forthcoming social and geographical diffusion of multiple drug resistant (MDR) HIV from present AIDS epicentres to the rest of the United States. [source] Nurses' perception of disaster: implications for disaster nursing curriculumJOURNAL OF CLINICAL NURSING, Issue 22 2009Fung WM Olivia Aims and objectives., The aims of the study were to identify nurses' perception of disaster, whether they considered some of the events that have occurred in Hong Kong to be disasters and the types of disastrous events that they considered likely in Hong Kong. Background., The frequent occurrence of disasters has caused concern internationally. When disaster strikes, the demands on nursing staff are much higher than those on other healthcare professionals. There is little understanding of the concept of disaster among nurses in Hong Kong. Design., This was a descriptive study. A questionnaire was used to explore nurses' perception of disaster. Method., The questionnaire was distributed to all registered nurses studying in a master's degree programme in a university in Hong Kong. Findings., Only 123 out of the 164 respondents (75%) gave a description of disaster in the open-ended question. Sixty-one per cent of them described unfortunate events with large numbers of victims as disasters. The ,Lan Kwai Fong tragedy , stampede caused by over-crowdedness' (90·9%) and the severe acute respiratory syndrome outbreak (89·6%) were commonly referred to as disasters in Hong Kong. Fires in tall buildings (61·6%), infectious disease outbreaks (61%) and stampedes caused by overcrowding (48·8%) were rated as the events most likely to happen in Hong Kong. Conclusion., Understanding how nurses perceive disaster and the likelihood of disastrous events is the initial step for disaster planning and the development of a disaster nursing curriculum in Hong Kong. Relevance to clinical practice., All nurses around the world should be equipped with knowledge and skills for disaster care. This study provides information and implications for related research and the development of a disaster nursing curriculum to meet the global demand for disaster preparedness. [source] Experimental challenge studies in Vietnamese catfish, Pangasianodon hypophthalmus (Sauvage), exposed to Edwardsiella ictaluri and Aeromonas hydrophilaJOURNAL OF FISH DISEASES, Issue 9 2010M Crumlish Abstract The two main diseases in the pangasius catfish industry are bacillary necrosis of Pangasianodon (BNP) and motile aeromonas septicaemia (MAS), where the aetiological agents have been identified as Edwardsiella ictaluri and Aeromonas hydrophila, respectively. In this study, apparently healthy Pangasianodon hypophthalmus were exposed to E. ictaluri, A. hydrophila or both bacterial species by intraperitoneal injection or immersion. There were 20 fish per treatment group, and the bacterial isolates used for the study were recovered from natural infections of BNP or MAS in farmed Vietnamese P. hypophthalmus. The results of the experimental infections mimicked the natural disease outbreaks reported from these pathogens in P. hypophthalmus. Furthermore, it was clearly demonstrated that E. ictaluri was only recovered from the fish exposed to the bacterium and not recovered from the animals receiving A. hydrophila. [source] Phenotypic, serological and genetic characterization of Flavobacterium psychrophilum strains isolated from salmonids in ChileJOURNAL OF FISH DISEASES, Issue 4 2009S Valdebenito Abstract Characterization of 20 Flavobacterium psychrophilum strains isolated from farmed Atlantic salmon and rainbow trout in Chile was done using phenotypic, antigenic and genetic techniques. Experimental infections were also performed to assess the virulence of two representative isolates and of the type strain. Biochemical and physiological analyses showed that Chilean F. psychrophilum strains, regardless of the host species, constitute a phenotypically very homogeneous group matching with previous descriptions of this pathogen. However, serological assays indicated the existence of antigenic heterogeneity with four patterns of serological reactions. The first group contained most (14 of 20) of the F. psychrophilum isolates showing cross-reaction with the antisera obtained against Atlantic salmon and rainbow trout isolates. Group 2 corresponded to four other rainbow trout isolates (1658, 1731, 1762 and 29009) that did not agglutinate with anti-1150 serum. Two minor serological groups were identified for the remaining isolates (Groups 3 and 4). Marked homogeneity was also revealed by genetic studies including 16S rRNA alleles, random amplified polymorphic DNA and REP-PCR showing that a major genetic group of F. psychrophilum may be dominant in disease outbreaks in farms. Restriction fragment length polymorphism of PCR analysis showed that gyrase genotypes B-S or B-R were found in Chilean isolates from rainbow trout and Atlantic salmon, whereas genotype A was not found. Virulence assays using Atlantic salmon indicated no relationship between the degree of pathogenicity and the host origin of the F. psychrophilum strains. [source] Isolation of a cyprinid herpesvirus 2 from goldfish, Carassius auratus (L.), in the UKJOURNAL OF FISH DISEASES, Issue 11 2007K R Jeffery Abstract Haematopoietic necrosis virus [cyprinid herpesvirus 2 (CyHV-2)] was isolated during disease outbreaks in goldfish, Carassius auratus, at an ornamental fish retail site in southern England in 2004. Signs of disease included lethargy and inappetence and were first seen after water temperatures increased from 14,15 to 19,21 °C. External gross pathology included pale patches on the gills and skin and internally the spleen was enlarged, often with distinctive white nodules. The most prominent histopathological changes observed were necrotic lesions in the spleen and kidney and focal patches of necrosis in the gill lamellae. Necrotic cells often contained nuclei with marginated chromatin and pale intranuclear inclusions. Ultrastructural examination of the spleen tissue revealed typical herpesvirus-like particles measuring 100 nm in diameter. The virus was isolated from extracts of gill tissue in KF-1 cells at 20 °C and oligonucleotide primer sets were designed based on conserved gene sequences and used to amplify viral DNA by polymerase chain reaction (PCR). The PCR assays were then used to detect the virus in DNA extracted from tissues sampled during earlier disease investigations at the retail site owner's holding facility in 2002 and 2003 and stored at ,70 °C since then. Polymerase gene-specific PCR amplification products obtained from tissue samples and from the virus isolated in cell culture shared 100% nucleotide sequence identity with the published sequence for CyHV-2. [source] Risk factors associated with mortalities attributed to infectious salmon anaemia virus in New Brunswick, CanadaJOURNAL OF FISH DISEASES, Issue 11 2005K L Hammell Abstract Outbreaks of unexplained mortalities attributed to infectious salmon anaemia (ISA) were examined in the 1996 year class of Atlantic salmon in three regions of New Brunswick, Canada. A total of 218 net pens at 14 sites deemed to have been exposed to ISA virus (ISAV) were surveyed for mortality records and management, environmental and host characteristics. Based on definitions of mortality patterns, clinical ISA disease outbreaks occurred in 106 net pens. There were eight sites in which >50% of net pens experienced ISA outbreaks during the study period. Factors related to their potential role in transmission of virus to new sites or new net pens at the same site were identified as sea lice vectors, divers visiting multiple sites, sites belonging to companies with more than one site, exposure to other year classes at the site, and proximity to other infected net pens. Host resistance factors associated with greater risk of outbreaks were identified as larger groupings, general health following smolt transfer, stressful husbandry procedures during growout, and health or productivity during colder water periods. Despite very close proximity between sites, modification of these management factors would probably influence the severity of mortalities caused by ISAV. [source] The transmission potential of Loma salmonae (Microspora) in the rainbow trout, Oncorhynchus mykiss (Walbaum), is dependent upon the method and timing of exposureJOURNAL OF FISH DISEASES, Issue 8 2001J M Ramsay The ability of a parasite to transmit from one fish to another is important in the dissemination of disease. Groups of 25 naive rainbow trout (RBT), Oncorhynchus mykiss (Walbaum), were exposed to Loma salmonae by feeding on the viscera (gills, hearts and spleens) from L. salmonae -infected donor RBT (DRBT) or by cohabitation with infected DRBT. Exposure occurred 3, 7, 11 and 15 weeks after the DRBT were infected. All naive RBT were examined 7 weeks post-exposure (PE) to the DRBT. Naive RBT, exposed to DRBT at week 3 PE, by feeding on viscera or by cohabitation, failed to develop visible branchial xenomas. Cohabiting naive RBT with DRBT, at week 7 PE and week 11 PE, resulted in the development of branchial xenomas. Xenomas failed to develop in naive RBT exposed via cohabitation to week 15 PE DRBT. Naive RBT, exposed by feeding on the viscera of DRBT at week 7 PE, week 11 PE and week 15 PE, developed branchial xenomas. The transmission potential of viscera from L. salmonae -infected DRBT at week 15 and week 20 PE was also examined. Naive RBT, fed with viscera free of visible branchial xenomas, from DRBT at week 15 PE and week 20 PE, developed branchial xenomas by week 7 PE. A polymerase chain reaction (PCR) was used to detect L. salmonae DNA from the water and sediments of a tank of L. salmonae -infected RBT at week 7 PE. The method and timing of exposure of naive fish to L. salmonae -infected fish are important in disease transmission and may be useful in predicting and preventing disease outbreaks in aquaculture. [source] Nodavirus infection of juvenile white seabass, Atractoscion nobilis, cultured in southern California: first record of viral nervous necrosis (VNN) in North AmericaJOURNAL OF FISH DISEASES, Issue 5 2001P A Curtis The viral aetiology of mass mortalities of white seabass, Atractoscion nobilis, cultured in southern California, USA was examined. Disease outbreaks occurred in juvenile fish reared at two culture facilities from June to December 1999, with clinical signs such as anorexia and erratic swimming motion. Microscopic lesions observed in moribund fish included marked vacuolation of brain, spinal cord and retina. The piscine nodavirus (Betanodavirus), the causative agent of viral nervous necrosis (VNN), was detected in the affected tissues by electron microscopy, indirect fluorescent antibody test (IFAT), reverse transcription,polymerase chain reaction (RT,PCR), and isolation in cell culture. The agent was identified as one of the four known genotypes of piscine nodavirus. In addition, a similar nodavirus was also detected in fish samples from disease outbreaks at the same facility in 1992. In the last decade, VNN has been reported among cultured populations of marine fish worldwide and this paper is the first record of the agent in North America. [source] Level of Concern and Precaution Taking Among Australians Regarding Travel During Pandemic (H1N1) 2009: Results From the 2009 Queensland Social SurveyJOURNAL OF TRAVEL MEDICINE, Issue 5 2010FACTM, FAFPHM, FFTM ACTM, FFTM RCPSG, Peter A. Leggat MD Background. Global disease outbreaks, such as the recent Pandemic (H1N1) 2009 (the so-called Swine flu), may have an impact on travel, including raising the concerns of travelers. The objective of this study was to examine the level of concern of Australians regarding travel during Pandemic (H1N1) 2009 and how this impacted on their travel. Methods. Data were collected by interviews as part of the Queensland Social Survey (QSS) 2009. Specific questions were incorporated regarding travel and Pandemic (H1N1) 2009. Multivariate logistic regression was used to analyze associations between demographic variables and concern and likelihood of cancelling travel. Results. There were 1,292 respondents (41.5% response rate). The sample was nearly equally divided between males and females (50.2% vs 49.8%). Younger people (18,34 y) were under-represented in the sample; older people (>55y) were over-represented in the sample. About half (53.2%) of respondents indicated some level of concern about Pandemic (H1N1) 2009 when traveling and just over one-third (35.5%) indicated they would likely cancel their air travel if they had a cough and fever that lasted more than one day. When cross-tabulating these responses, people who expressed concern regarding Pandemic (H1N1) 2009 when they traveled were more likely than those without concern to cancel their air travel if they had a cough and fever lasting more than one day (44.7% vs 27.7%, ,2 = 33.53, p < 0.001). People with higher levels of education [adjusted odds ratio (AOR): 0.651], people with higher incomes (AOR: 0.528) and people living outside of metropolitan Southeast Queensland (AOR: 0.589) were less likely to be concerned about Pandemic (H1N1) 2009 when traveling, and younger people (AOR: 0.469) were less likely than others to cancel travel if they had a cough and fever. Conclusions. Pandemic (H1N1) 2009 was of some concern to more than half of Queensland travelers. None-the-less, the majority of Queenslanders would not have postponed their own travel, even if they exhibited symptoms consistent with Pandemic (H1N1) 2009. [source] Subtyping of Bacterial Foodborne PathogensNUTRITION REVIEWS, Issue 7 2002Martin Wiedmann D.V.M. Ph.D. Phenotype-based and DNA-based subtyping methods allow for differentiation of bacterial isolates beyond the species and subspecies level. Bacterial subtyping methods not only have improved our ability to detect and track foodborne disease outbreaks, but also represent tools to track sources of bacterial contamination throughout the food system. The use of subtyping methods furthermore provides an opportunity to better understand the population genetics, epidemiology, and ecology of different foodborne pathogens. The last 5 years have seen tremendous advancement in the development of sensitive, rapid, automated, and increasingly easy-to-use molecular subtyping methods for a variety of different bacterial foodborne pathogens. This review will highlight key aspects of different subtyping methods for bacterial foodborne pathogens and provide examples of their applications in public health, food safety, epidemiology, and population genetics. Molecular subtyping and characterization methods may also facilitate the development of a novel framework for tracking, preventing, and regulating foodborne bacterial diseases, which is based on evolutionary relationships and genetic characteristics rather than traditional species definitions. [source] A method for selecting and monitoring medication sales for surveillance of gastroenteritis,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 10 2010Camille Pelat Abstract Purpose Monitoring appropriate categories of medication sales can provide early warning of certain disease outbreaks. This paper presents a methodology for choosing and monitoring medication sales relevant for the surveillance of gastroenteritis and assesses the operational characteristics of the selected medications for early warning. Methods Acute diarrhoea incidences in mainland France were obtained from the Sentinelles network surveillance system for the period 2000,2009. Medication sales grouped by therapeutic classes were obtained on the same period. Hierarchical clustering was used to select therapeutic classes correlating with disease incidence over the period. Alert thresholds were defined for the selected therapeutic classes. Single and multiple voter algorithms were investigated for outbreak detection based on sales crossing the thresholds. Sensitivity and specificity were calculated respective to known outbreaks periods. Results Four therapeutic classes were found to cluster with acute diarrhoea incidence. The therapeutic class other antiemetic and antinauseants had the best sensitivity (100%) and timeliness (1.625 weeks before official alerts), for a false alarm rate of 5%. Multiple voter algorithm was the most efficient with the rule: ,Emit an outbreak alert when at least three therapeutic classes are over their threshold' (sensitivity 100%, specificity 95%, timeliness 1.750 weeks before official alerts). Conclusions The presented method allowed selection of relevant therapeutic classes for surveillance of a specific condition. Multiple voter algorithm based on several therapeutic classes performed slightly better than the best therapeutic class alone, while improving robustness against abrupt changes occurring in a single therapeutic class. Copyright © 2010 John Wiley & Sons, Ltd. [source] Effects of food supplementation on home-range size, reproductive success, productivity and recruitment in a small population of Iberian lynxANIMAL CONSERVATION, Issue 1 2010J. V. López-Bao Abstract In a conservation context, food supplementation is a management tool used to reverse the decline of food-limited populations by means of positive changes in behaviour and fitness that may be reflected in population parameters. The critically endangered Iberian lynx Lynx pardinus has suffered a dramatic decline primarily because of the severe drop of its main prey, the European wild rabbit Oryctolagus cuniculus. To reverse this situation, a food supplementation programme has been implemented in Doñana, south-west Spain, since 2002. In this study, we assess the utility of providing artificial food to reduce home-range (HR) size, and to increase productivity, survival and recruitment in a scenario of low lynx density, as compared with reference data from the same population in the absence of extra food. Food supplementation produced a significant contraction of core areas, but not of complete lynx HRs. We did not detect any significant change in productivity or dispersal rates, but supplementation could have helped transient adult lynx to settle down. The positive effects of food supplementation may have been partly countered by factors such as inbreeding, Allee effects and disease outbreaks, whose effects may have been exacerbated in this small lynx population. Food supplementation, however, proved useful to retain individuals, to keep range sizes within their normal range of values, thus maintaining spatial organization, and to allow lynx reproduction and kitten survival in areas with very low prey density. Therefore, we recommend keeping an extensive and intensive supplementary feeding programme until the density of wild rabbits will enable the viability of this endangered lynx population. [source] Efficacy of an experimentally inactivated Streptococcus agalactiae vaccine in Nile tilapia (Oreochromis niloticus) reared in BrazilAQUACULTURE RESEARCH, Issue 10 2010Lucienne Garcia Pretto-Giordano Abstract Tilapia aquaculture is one of the fastest-growing segments of fish production in Brazil. Nile tilapia (Oreochromis niloticus) is largely cultivated in the state of Parana, where Streptococcus agalactiae is the cause of severe disease outbreaks. The objective of this paper was to evaluate an inactivated S. agalactiae vaccine in tilapia for the control of streptococcal disease outbreaks. Tilapia, weighing approximately 20 g each, were intraperitoneally (i.p.) inoculated with 0.1 mL of the vaccine at a dose of 2.0 × 108 colony-forming unit (CFU) mL,1. One group of tilapia (treatment 1) received one vaccine dose, and the other group of tilapia (treatment 2) received two doses, with an interval of 21 days. The control group was i.p. inoculated with 0.1 mL tryptic soy broth fish,1. Immunized and control tilapia were i.p. challenged with 0.1 mL of 3.0 × 107 CFU mL,1 at 30 days post vaccination. The fish were monitored daily for disease signs and for mortality for 16 days post challenge. A statistically significant difference (P=0.0045) was found between the mortality of treatments 1 and 2. The value of relative per cent of survival of 83.6% and 96.4%, respectively, indicate that this vaccine was efficient in Nile tilapia. [source] Priorities for planning and prevention of infectious disease outbreaks at large international eventsAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 5 2007Cate Wallace No abstract is available for this article. [source] Serovar profiling of Haemophilus parasuis on Australian farms by sampling live pigsAUSTRALIAN VETERINARY JOURNAL, Issue 7 2010C Turni Objective Investigate the diversity of serovars of Haemophilus parasuis (Hps) present in Australian pig herds. Design Nasal swabs were used to obtain multiple isolates of Hps, which were grouped first by genotyping and then by serotyping representative isolates. Procedure Swabs were taken from the nasal cavity of just-weaned healthy pigs from multiparous sows on 12 farms and from post-weaned pigs of multiparous sows on 1 farm. On 5 of the 13 farms, nasal swabs were also obtained from pigs showing clinical signs suggestive of Glässer's disease. On a further 7 farms, nasal swabs were obtained only from pigs with clinical signs suggestive of Glässer's disease. Results A total of 556 Hps isolates were genotyped, and 150 isolates were serotyped. Hps was detected on 19 of the 20 farms, including 2 farms with a long history of freedom from Glässer's disease. Isolates of Hps belonging to serovars regarded as potentially pathogenic were obtained from healthy pigs at weaning on 8 of the 10 farms with a history of Glässer's disease outbreaks. Sampling 213 sick pigs yielded 115 isolates of Hps, 99 of which belonged to serovars that were either potentially pathogenic or of unknown pathogenicity. Only 16 isolates from these 213 sick pigs were of a serovar known to be non-pathogenic. Conclusion Healthy pigs contain a range of Hps serovars, even on farms free of Glässer's disease. Nasal swabbing of both healthy and sick pigs seems a useful method of serovar profiling of farms. [source] Review of identification and traceability legislation for pigs in AustraliaAUSTRALIAN VETERINARY JOURNAL, Issue 7 2007N Schembri Objective To assess Australia's capability to trace pig movements in the event of an exotic disease outbreak by highlighting the commonalities and inconsistencies between the various state and territory legislations in defining how pig producers are located; their pigs are identified; and whether movement records are required post,farm gate. Procedure A review of the identification and traceability legislation applicable to pigs in Australia was undertaken over a 6 month period. The appropriate legislative Acts and Regulations were downloaded from the Australasian Legal Information Institute internet site (http://www.austlii.edu.au/) and reviewed. Results The Australian pig industry currently uses the branding method (tattooing) to identify pigs for sale or slaughter, with each state responsible for its own pig identification and movement control systems. Areas of concern identified included inconsistencies with the minimum weight or age of pigs that require identification; discrepancies between methods of tattoo registration and shortfalls in documentation for recording pig movements. Conclusion Our findings highlight the flaws in Australia's current state legislative Acts and Regulations for identifying pigs and tracking their movements, which compromise the ability of jurisdictions to meet the endorsed National Performance Standards. Improvements in these areas will enhance security to the pig and other livestock industries in the event of future exotic disease outbreaks. [source] Rapid differentiation of current infectious bronchitis virus vaccine strains and field isolates in AustraliaAUSTRALIAN VETERINARY JOURNAL, Issue 1-2 2006K. MARDANI Objective Rapid differentiation of vaccine strains of infectious bronchitis virus (IBV) from wild type strains would enhance investigations of disease outbreaks. This study aimed to develop a reverse transcription-polymerase chain reaction (RT-PCR) assay to differentiate between Australian vaccine strains of IBV and field isolates. Procedure A fragment of 6.5 kilobases that contains the S, M and N genes was amplified by RT-PCR from ten different IBV strains, including vaccine strains and field isolates, and then sequenced. Results Comparison of the sequences of these strains revealed a deletion of 58 bases in the 3, untranslated region (UTR) of IBV vaccine strains but not in the field isolates. Two primers were designed to amplify a fragment of the 3, UTR that differed in size between the vaccine strains and field isolates. RT-PCR was performed using these two primers to screen 20 IBV strains, including field isolates and the vaccine strains. All strains were correctly identified as either vaccine strains or field isolates. Conclusion This procedure is a rapid, sensitive and inexpensive method for discrimination between most current Australian vaccine strains and field isolates of IBV. [source] | |||||||||||||||||||