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Emerging Infectious Diseases (emerging + infectious_diseases)
Selected AbstractsQuarantine in Severe Acute Respiratory Syndrome (SARS) and Other Emerging Infectious DiseasesTHE JOURNAL OF LAW, MEDICINE & ETHICS, Issue 2003Jane Speakman No abstract is available for this article. [source] Effects of atrazine and iridovirus infection on survival and life-history traits of the long-toed salamander (Ambystoma macrodactylum)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2006Diane Forson Abstract Environmental contaminants and emerging infectious diseases are implicated as factors contributing to global amphibian declines. However, few studies have tested the interaction of these factors. We exposed six-week-old, larval long-toed salamanders (Ambystoma macrodactylum) to Ambystoma tigrinum virus (ATV; 0 or 103.5 plaque-forming units/ml) and sublethal concentrations of atrazine (0, 1.84, 18.4, and 184 ,g/L) in a 4 × 2 factorial design for 30 d. We tested the effects of atrazine and virus on mass and snout-vent length (SVL) at metamorphosis and larval period as well as on rates of mortality and viral infectivity. We confirmed ATV transmission to A. macrodactylum via polymerase chain reaction, but infection rates were lower than expected, consistent with the theory predicting lower pathogen transmission to nonnative hosts. Larvae exposed to both atrazine and ATV had lower levels of mortality and ATV infectivity compared to larvae exposed to virus alone, suggesting atrazine may compromise virus efficacy. The highest atrazine level (184 ,g/L) accelerated metamorphosis and reduced mass and SVL at metamorphosis significantly relative to controls. Exposure to ATV also significantly reduced SVL at metamorphosis. The present study suggests moderate concentrations of atrazine may ameliorate effects of ATV on long-toed salamanders, whereas higher concentrations initiate metamorphosis at a smaller size, with potential negative consequences to fitness. [source] Implementing the Amphibian Conservation Action PlanINTERNATIONAL ZOO YEARBOOK, Issue 1 2008R. D. MOORE The Global Amphibian Assessment, completed in 2004, revealed that over 32% of the c. 6000 amphibian species known worldwide are threatened with extinction. This staggering figure exceeds rates of imperilment for both birds (12%) and mammals (23%). Amphibians face threats from traditional factors, such as habitat loss, unsustainable use, invasive species and pollution. These stresses are compounded by more novel threats, such as emerging infectious diseases and climate change, which are unimpeded by protected-area boundaries. A Summit was convened in September 2005 to devise a unified strategy for amphibian conservation in the form of the Amphibian Conservation Action Plan (ACAP; available at http://www.amphibians.org/). The ACAP outlines a 5 year plan to curtail the decline and extinction of amphibians, and focuses on 11 themes, each with an associated budget. The total estimated cost of abating the current trend comes to US $400 million over the next 5 years. While this may appear daunting, it serves to highlight the urgency of the situation and draws attention to the need to steer limited resources towards the conservation of this vulnerable group. The ACAP is a call for help to governments, zoos and aquariums, civilians and researchers alike. We need to work together if we are going to succeed in stemming a mass extinction spasm affecting an entire class of vertebrates. The IUCN/SSC (The World Conservation Union/Species Survival Commission) Amphibian Specialist Group (ASG; http://www.amphibians.org/), formed after the Summit, is working to implement the ACAP by stimulating, developing and executing practical programmes to conserve amphibians and their habitats around the world. In addition, the ASG is supporting a global web of partners to develop funding, capacity and technology transfer to achieve shared, strategic amphibian conservation goals. [source] The historical biogeography of co-evolution: emerging infectious diseases are evolutionary accidents waiting to happenJOURNAL OF BIOGEOGRAPHY, Issue 8 2005Daniel R. Brooks Abstract Ecological fitting refers to interspecific associations characterized by ecologically specialized, yet phylogenetically conservative, resource utilization. During periods of biotic expansion, parasites and hosts may disperse from their areas of origin. In conjunction with ecological fitting, this sets the stage for host switching without evolving novel host utilization capabilities. This is the evolutionary basis of emerging infectious diseases (EIDs). Phylogenetic analysis for comparing trees (PACT) is a method developed to delineate both general and unique historically reticulated and non-reticulated relationships among species and geographical areas, or among parasites and their hosts. PACT is based on ,Assumption 0', which states that all species and all hosts in each input phylogeny must be analysed without modification, and the final analysis must be logically consistent with all input data. Assumption 0 will be violated whenever a host or area has a reticulated history with respect to its parasites or species. PACT includes a Duplication Rule, by which hosts or areas are listed for each co-evolutionary or biogeographical event affecting them, which satisfies Assumption 0 even if there are reticulations. PACT maximizes the search for general patterns by using Ockam's Razor , duplicate only enough to satisfy Assumption 0. PACT applied to the host and geographical distributions of members of two groups of parasitic helminths infecting anthropoid primates indicates a long and continuous association with those hosts. Nonetheless, c. 30% of the host associations are due to host switching. Only one of those involves non-primate hosts, suggesting that most were constrained by resource requirements that are phylogenetically conservative among primates (ecological fitting). In addition, most of the host switches were associated with episodes of biotic expansion, also as predicted by the ecological fitting view of EIDs. [source] Identifying the Gaps Between Biodefense Researchers, Public Health, and Clinical Practice in a Rural CommunityTHE JOURNAL OF RURAL HEALTH, Issue 3 2008Jessica M. Van Fleet-Green BS ABSTRACT:,Objective:It is essential for health care professionals to be prepared for a bioterrorist attack or other public health emergency. We sought to determine how well biodefense and emerging infectious disease research information was being disseminated to rural health care providers, first responders, and public health officials. Methods: Semi-structured interviews were conducted at a federally funded research institution and a rural community in Washington state with 10 subjects, including researchers, community physicians and other health care providers, first responders, and public health officials. Results: The interviews suggest there is inadequate information dissemination regarding biodefense and emerging infectious disease research and an overall lack of preparedness for a bioterrorist event among rural clinicians and first responders. Additionally, a significant communication gap exists between public health and clinical practice regarding policies for bioterrorism and emerging infectious disease. There was, however, support and understanding for the research enterprise in bioterrorism. Conclusions: Biodefense preparedness and availability of information about emerging infectious diseases continues to be a problem. Methods for information dissemination and the relationships between public health officials and clinicians in rural communities need to be improved. [source] The origin of human pathogens: evaluating the role of agriculture and domestic animals in the evolution of human diseaseBIOLOGICAL REVIEWS, Issue 3 2006Jessica M. C. Pearce-Duvet ABSTRACT Many significant diseases of human civilization are thought to have arisen concurrently with the advent of agriculture in human society. It has been hypothesised that the food produced by farming increased population sizes to allow the maintenance of virulent pathogens, i.e. civilization pathogens, while domestic animals provided sources of disease to humans. To determine the relationship between pathogens in humans and domestic animals, I examined phylogenetic data for several human pathogens that are commonly evolutionarily linked to domestic animals: measles, pertussis, smallpox, tuberculosis, taenid worms, and falciparal malaria. The majority are civilization pathogens, although I have included others whose evolutionary origins have traditionally been ascribed to domestic animals. The strongest evidence for a domestic-animal origin exists for measles and pertussis, although the data do not exclude a non-domestic origin. As for the other pathogens, the evidence currently available makes it difficult to determine if the domestic-origin hypothesis is supported or refuted; in fact, intriguing data for tuberculosis and taenid worms suggests that transmission may occur as easily from humans to domestic animals. These findings do not abrogate the importance of agriculture in disease transmission; rather, if anything, they suggest an alternative, more complex series of effects than previously elucidated. Rather than domestication, the broader force for human pathogen evolution could be ecological change, namely anthropogenic modification of the environment. This is supported by evidence that many current emerging infectious diseases are associated with human modification of the environment. Agriculture may have changed the transmission ecology of pre-existing human pathogens, increased the success of pre-existing pathogen vectors, resulted in novel interactions between humans and wildlife, and, through the domestication of animals, provided a stable conduit for human infection by wildlife diseases. [source] Guidelines for the validation and application of typing methods for use in bacterial epidemiologyCLINICAL MICROBIOLOGY AND INFECTION, Issue 2007A. Van Belkum For bacterial typing to be useful, the development, validation and appropriate application of typing methods must follow unified criteria. Over a decade ago, ESGEM, the ESCMID (Europen Society for Clinical Microbiology and Infectious Diseases) Study Group on Epidemiological Markers, produced guidelines for optimal use and quality assessment of the then most frequently used typing procedures. We present here an update of these guidelines, taking into account the spectacular increase in the number and quality of typing methods made available over the past decade. Newer and older, phenotypic and genotypic methods for typing of all clinically relevant bacterial species are described according to their principles, advantages and disadvantages. Criteria for their evaluation and application and the interpretation of their results are proposed. Finally, the issues of reporting, standardisation, quality assessment and international networks are discussed. It must be emphasised that typing results can never stand alone and need to be interpreted in the context of all available epidemiological, clinical and demographical data relating to the infectious disease under investigation. A strategic effort on the part of all workers in the field is thus mandatory to combat emerging infectious diseases, as is financial support from national and international granting bodies and health authorities. [source] | |||||||||||||