Seasonal Fluctuations of Astrovirus,But Not Coronavirus Shedding in Bats Inhabiting Human-Modified Tropical Forests

Emerging infectious diseases (EIDs) are considered a major threat to global health. Most EIDs appear to result from increased contact between wildlife and humans, especially when humans encroach into formerly pristine habitats. Habitat deterioration may also negatively affect the physiology and health of wildlife species, which may eventually lead to a higher susceptibility to infectious agents and/or increased shedding of the pathogens causing EIDs. Bats are known to host viruses closely related to important EIDs. Here, we tested in a paleotropical forest with ongoing logging and fragmentation, whether habitat disturbance influences the occurrence of astro- and coronaviruses in eight bat species. In contrast to our hypothesis, anthropogenic habitat disturbance was not associated with corona- and astrovirus detection rates in fecal samples. However, we found that bats infected with either astro- or coronaviruses were likely to be coinfected with the respective other virus. Additionally, we identified two more risk factors influencing astrovirus shedding. First, the detection rate of astroviruses was higher at the beginning of the rainy compared to the dry season. Second, there was a trend that individuals with a poor body condition had a higher probability of shedding astroviruses in their feces. The identification of risk factors for increased viral shedding that may potentially result in increased interspecies transmission is important to prevent viral spillovers from bats to other animals, including humans.     

Emerging infectious diseases of plants: pathogen pollution, climate change and agrotechnology drivers

Emerging infectious diseases (EIDs) pose threats to conservation and public health. Here, we apply the definition of EIDs used in the medical and veterinary fields to botany and highlight a series of emerging plant diseases. We include EIDs of cultivated and wild plants, some of which are of significant conservation concern. The underlying cause of most plant EIDs is the anthropogenic introduction of parasites, although severe weather events are also important drivers of disease emergence. Much is known about crop plant EIDs, but there is little information about wild-plant EIDs, suggesting that their impact on conservation is underestimated. We conclude with recommendations for improving strategies for the surveillance and control of plant EIDs.     

Deciphering the bat virome catalog to better understand the ecological diversity of bat viruses and the bat origin of emerging infectious diseases

Studies have demonstrated that ~60%–80% of emerging infectious diseases (EIDs) in humans originated from wild life. Bats are natural reservoirs of a large variety of viruses, including many important zoonotic viruses that cause severe diseases in humans and domestic animals. However, the understanding of the viral population and the ecological diversity residing in bat populations is unclear, which complicates the determination of the origins of certain EIDs. Here, using bats as a typical wildlife reservoir model, virome analysis was conducted based on pharyngeal and anal swab samples of 4440 bat individuals of 40 major bat species throughout China. The purpose of this study was to survey the ecological and biological diversities of viruses residing in these bat species, to investigate the presence of potential bat-borne zoonotic viruses and to evaluate the impacts of these viruses on public health. The data obtained in this study revealed an overview of the viral community present in these bat samples. Many novel bat viruses were reported for the first time and some bat viruses closely related to known human or animal pathogens were identified. This genetic evidence provides new clues in the search for the origin or evolution pattern of certain viruses, such as coronaviruses and noroviruses. These data offer meaningful ecological information for predicting and tracing wildlife-originated EIDs.     

Synanthropy of Wild Mammals as a Determinant of Emerging Infectious Diseases in the Asian–Australasian Region

Humans create ecologically simplified landscapes that favour some wildlife species, but not others. Here, we explore the possibility that those species that tolerate or do well in human-modified environments, or 'synanthropic' species, are predominantly the hosts of zoonotic emerging and re-emerging infectious diseases (EIDs). We do this using global wildlife conservation data and wildlife host information extracted from systematically reviewed emerging infectious disease literature. The evidence for this relationship is examined with special emphasis on the Australasian, South East Asian and East Asian regions. We find that synanthropic wildlife hosts are approximately 15 times more likely than other wildlife in this region to be the source of emerging infectious diseases, and this association is essentially independent of the taxonomy of the species. A significant positive association with EIDs is also evident for those wildlife species of low conservation risk. Since the increase and spread of native and introduced species able to adapt to human-induced landscape change is at the expense of those species most vulnerable to habitat loss, our findings suggest a mechanism linking land conversion, global decline in biodiversity and a rise in EIDs of wildlife origin.     

The Role of Ecotones in Emerging Infectious Diseases

Recognition of the significance of the boundary between ecological systems, often referred to as the ecotone, has a long history in the ecological sciences and in zoonotic disease research. More recent research in landscape ecology has produced an expanded view of ecotones and elaboration of their characteristics and functions in ecosystems. Parallel research on emerging infectious diseases (EIDs) and the causes of increased rates of pathogen transmission, spread, and adaptation suggests a correspondence between ecotonal processes and the ecological and evolutionary processes responsible for zoonotic and vector-borne emerging infections. A review of the literature suggests that ecotones play a role in a number of the most important EIDs. Yet these are the only diseases for which specific landscape ecological information exists in the literature or disease reports. However, the similar disease ecologies of these with about half of the approximately 130 zoonotic EIDs suggests ecotones, particularly their anthropogenic origination or modification, may be generally associated with ecotones and the global trend of increasing EIDs.     

The Global One Health Paradigm: Challenges and Opportunities for Tackling Infectious Diseases at the Human,Animal, and Environment Interface in Low-Resource Settings

Zoonotic infectious diseases have been an important concern to humankind for more than 10,000 years. Today, approximately 75% of newly emerging infectious diseases (EIDs) are zoonoses that result from various anthropogenic, genetic, ecologic, socioeconomic, and climatic factors. These interrelated driving forces make it difficult to predict and to prevent zoonotic EIDs. Although significant improvements in environmental and medical surveillance, clinical diagnostic methods, and medical practices have been achieved in the recent years, zoonotic EIDs remain a major global concern, and such threats are expanding, especially in less developed regions. The current Ebola epidemic in West Africa is an extreme stark reminder of the role animal reservoirs play in public health and reinforces the urgent need for globally operationalizing a One Health approach. The complex nature of zoonotic diseases and the limited resources in developing countries are a reminder that the need for implementation of Global One Health in low-resource settings is crucial. The Veterinary Public Health and Biotechnology (VPH-Biotec) Global Consortium launched the International Congress on Pathogens at the Human-Animal Interface (ICOPHAI) in order to address important challenges and needs for capacity building. The inaugural ICOPHAI (Addis Ababa, Ethiopia, 2011) and the second congress (Porto de Galinhas, Brazil, 2013) were unique opportunities to share and discuss issues related to zoonotic infectious diseases worldwide. In addition to strong scientific reports in eight thematic areas that necessitate One Health implementation, the congress identified four key capacity-building needs: (1) development of adequate science-based risk management policies, (2) skilled-personnel capacity building, (3) accredited veterinary and public health diagnostic laboratories with a shared database, and (4) improved use of existing natural resources and implementation. The aim of this review is to highlight advances in key zoonotic disease areas and the One Health capacity needs.     

The use of molecular xenomonitoring for surveillance of mosquito-borne diseases

The scientific community recognizes that molecular xenomonitoring (MX) can allow infected mosquitoes to serve as a proxy for human infection in vector-borne disease surveillance, but developing reliable MX systems for programmatic use has been challenging. The primary aim of this article is to examine the available evidence to recommend how MX can best be used for various purposes. Although much of the literature published within the last 20 years focuses on using MX for lymphatic filariasis elimination, a growing body of evidence supports its use in early warning systems for emerging infectious diseases (EIDs). An MX system design must consider the goal and target (e.g. diseases targeted for elimination versus EIDs), mosquito and pathogen characteristics, and context (e.g. setting and health system). MX is currently used as a ‘supplement’ to human surveillance and will not be considered as a ‘replacement’ until the correlation between pathogen-infection rates in human and mosquito populations is better understood. Establishing such relationships may not be feasible in elimination scenarios, due to increasingly dwindling human infection prevalence after successful control, but may still be possible for EIDs and in integrated disease surveillance systems.This article is part of the theme issue ‘Novel control strategies for mosquito-borne diseases''.     

Infectious disease and amphibian population declines

Abstract. A series of recent papers have implicated pathogens and parasites in amphibian population declines. Here, we review evidence on the link between infectious disease and amphibian population declines. We conclude that available data provide the clearest link for the fungal disease amphibian chytridiomycosis, although other pathogens are also implicated. We suggest additional experimental and observational data that need to be collected to provide further support that these other pathogens are associated with declines. We suggest that, in common with many emerging infectious diseases (EIDs) of humans, domestic animals and other wildlife species, emergence of chytridiomycosis may be driven by anthropogenic introduction (pathogen pollution). Finally, we review a number of recent advances in the host–parasite ecology of chytridiomycosis that help explain its emergence and impact.     

Genetic evidence of <Emphasis Type="Italic">Ranavirus</Emphasis> in toe clips: an alternative to lethal sampling methods

Amphibian populations have been undergoing declines on a global scale. Among the many threats to these populations are emergent infectious diseases (EIDs). The Ranavirus in particular has been found within many declining amphibian populations. Although non-lethal sampling methods exist for some amphibian groups, such as salamanders, the anurans are traditionally tested using a lethal method. By comparing traditional liver samples and a new non-lethal method of toe clipping we prove that the Ranavirus can also be determined in frogs using a non-lethal method, a much needed tool in threatened populations. This method will allow for ranaviral detection without further impacting declining populations, and can further be used for other research questions.     

The Role of Immunotoxic Environmental Contaminants in Facilitating the Emergence of Infectious Diseases in Marine Mammals

A series of high profile outbreaks of newly described diseases in humans, domestic animals and wildlife has attracted widespread interest in the topic of Emerging Infectious Diseases (EIDs). Marine mammals are no exception: since 1987 several mass mortalities have been observed following infection with viruses previously undescribed in the populations or species in question. As with terrestrial examples, some of these outbreaks have followed either migrations associated with large-scale ecological changes or the introduction of virus from domestic animals. However, marine mammals warrant special concern in the context of emerging infectious diseases: they typically occupy high trophic levels and can therefore be highly contaminated with immunotoxic chemicals. Persistent Organic Pollutants (POPs), including polychlorinated -biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), -dibenzofurans (PCDFs) and related compounds, are demonstrated immunotoxicants in laboratory animals, as well as marine mammals. Immunotoxic contaminants may represent a factor that facilitates disease emergence, and may lead to the creation of susceptible “reservoirs” for new pathogens in contaminated marine mammal populations. The factors underlying the emergence and exchange of pathogens among marine mammals, domestic animals, and humans demand multidisciplinary study and invite regulatory and conservation scrutiny. The complexity of this issue may be best addressed through an integrated human and ecological risk assessment framework.     

综述与专论: 树鼩病毒感染模型的研究新进展

病毒感染引起的疾病接近中国主要传染病发病率的一半,也是传染病致死的主要病因。建立与人类亲缘关系较近、方便有效的感染人类病毒的动物模型,对了解病毒的生物学特性、感染致病机理及制定有效防控措施具有重要意义。树鼩作为灵长类动物的近亲,与人类在生理生化、基因组学等方面的相似性远高于大鼠、小鼠等常用啮齿类实验动物,并具有个体小、便于实验操作、饲养成本低、能感染多种人类病毒等特点,作为动物模型在病毒感染性疾病研究中突显优势和潜能。本文从地区分布、进化、生物学特性等方面,阐述了树鼩作为动物模型应用于病毒感染性疾病研究的优势,包括在乙型肝炎病毒、甲型肝炎病毒,及其他病毒感染疾病研究中的进展。     

Viruses in neurodegenerative diseases: More than just suspects in crimes

Neurodegenerative diseases (NDs) such as Alzheimer’s and Parkinson’s disease are fatal neurological diseases that can be of idiopathic, genetic, or even infectious origin, as in the case of transmissible spongiform encephalopathies. The etiological factors that lead to neurodegeneration remain unknown but likely involve a combination of aging, genetic risk factors, and environmental stressors. Accumulating evidence hints at an association of viruses with neurodegenerative disorders and suggests that virus-induced neuroinflammation and perturbation of neuronal protein quality control can be involved in the early steps of disease development. In this review, we focus on emerging evidence for a correlation between NDs and viral infection and discuss how viral manipulations of cellular processes can affect the formation and dissemination of disease-associated protein aggregates.     

Host nutritional status: the neglected virulence factor

The emergence of new infectious diseases and old diseases with new pathogenic properties is a burgeoning worldwide problem. Severe acute respiratory syndrome (SARS) and acquired immune deficiency syndrome (AIDS) are just two of the most widely reported recent emerging infectious diseases. What are the factors that contribute to the rapid evolution of viral species? Various hypotheses have been proposed, all involving opportunities for virus spread (for example, agricultural practices, climate changes, rainforest clearing or air travel). However, the nutritional status of the host, until recently, has not been considered a contributing factor to the emergence of infectious disease. In this review, we show that host nutritional status can influence not only the host response to the pathogen, but can also influence the genetic make-up of the viral genome. This latter finding markedly changes our concept of host-pathogen interactions and creates a new paradigm for the study of such phenomena.     

Epidemiological study of zoonoses derived from humans in captive chimpanzees

Emerging infectious diseases (EIDs) in wildlife are major threats both to human health and to biodiversity conservation. An estimated 71.8 % of zoonotic EID events are caused by pathogens in wildlife and the incidence of such diseases is increasing significantly in humans. In addition, human diseases are starting to infect wildlife, especially non-human primates. The chimpanzee is an endangered species that is threatened by human activity such as deforestation, poaching, and human disease transmission. Recently, several respiratory disease outbreaks that are suspected of having been transmitted by humans have been reported in wild chimpanzees. Therefore, we need to study zoonotic pathogens that can threaten captive chimpanzees in primate research institutes. Serological surveillance is one of several methods used to reveal infection history. We examined serum from 14 captive chimpanzees in Japanese primate research institutes for antibodies against 62 human pathogens and 1 chimpanzee-borne infectious disease. Antibodies tested positive against 29 pathogens at high or low prevalence in the chimpanzees. These results suggest that the proportions of human-borne infections may reflect the chimpanzee’s history, management system in the institute, or regional epidemics. Furthermore, captive chimpanzees are highly susceptible to human pathogens, and their induced antibodies reveal not only their history of infection, but also the possibility of protection against human pathogens.     

Introducing One Health to the Ethical Debate About Zoonotic Diseases in Southeast Asia

Pandemic plans recommend phases of response to an emergent infectious disease (EID) outbreak, and are primarily aimed at preventing and mitigating human‐to‐human transmission. These plans carry presumptive weight and are increasingly being operationalized at the national, regional and international level with the support of the World Health Organization (WHO). The conventional focus of pandemic preparedness for EIDs of zoonotic origin has been on public health and human welfare. However, this focus on human populations has resulted in strategically important disciplinary silos. As the risks of zoonotic diseases have implications that reach across many domains outside traditional public health, including anthropological, environmental, and veterinary fora, a more inclusive ecological perspective is paramount for an effective response to future outbreaks.     

Emerging viral infections in a rapidly changing world

Emerging viral infections in both humans and animals have been reported with increased frequency in recent years. Recent advances have been made in our knowledge of some of these, including severe acute respiratory syndrome-associated coronavirus, influenza A virus, human metapneumovirus, West Nile virus and Ebola virus. Research efforts to mitigate their effects have concentrated on improved surveillance and diagnostic capabilities, as well as on the development of vaccines and antiviral agents. More attention needs to be given to the identification of the underlying causes for the emergence of infectious diseases, which are often related to anthropogenic social and environmental changes. Addressing these factors might help to decrease the rate of emergence of infectious diseases and allow the transition to a more sustainable society.     

Charles Nicolle and the accomplishments of his scientific thought

The author presents in this study the achievements of the scientific thought of Charles Nicolle, chiefly on the basis of two notions: the asymptomatic diseases and the destiny of infectious diseases. Recalling the factors which prevailing about the career of Charles Nicolle, he shows that the asymptomatic diseases became a fundamental notion in infectious pathology as human, animal, viral, bacterial and parasitic diseases. The notion allowed him to open the study of pathogen agents on the fields of the environment, so enriching the epidemiology, the prophylaxis and the medical ecology. After the notion of specificity of microbes pointed out by Pasteur, Charles Nicolle enlarged their implications and conceived the infinite complexity of microbes. The first he introduced in microbiology the notion of mutation and foresaw the birth, the evolution and the death of the infectious diseases. Not so long time after and now these anticipations has been proved.     

Immunoprophylaxis in fish by injection of mouse antibody genes

Antibodies are a crucial part of the body's specific defense against infectious diseases and have considerable potential as therapeutic and prophylactic agents in humans and animals. The development of recombinant single-chain antibodies allows a genetic application strategy for prevention of infectious diseases. To test this in a fish model, a gene construct encoding a neutralizing single-chain antibody to the fish-pathogenic rhabdovirus VHSV (viral hemorrhagic septicemia virus) was administered to rainbow trout by intramuscular injection of plasmid DNA. Circulating recombinant antibodies could later be detected in the fish, and protective immunity to the viral disease was established.     

Increased avian diversity is associated with lower incidence of human West Nile infection: observation of the dilution effect

Recent infectious disease models illustrate a suite of mechanisms that can result in lower incidence of disease in areas of higher disease host diversity--the 'dilution effect'. These models are particularly applicable to human zoonoses, which are infectious diseases of wildlife that spill over into human populations. As many recent emerging infectious diseases are zoonoses, the mechanisms that underlie the 'dilution effect' are potentially widely applicable and could contribute greatly to our understanding of a suite of diseases. The dilution effect has largely been observed in the context of Lyme disease and the predictions of the underlying models have rarely been examined for other infectious diseases on a broad geographic scale. Here, we explored whether the dilution effect can be observed in the relationship between the incidence of human West Nile virus (WNV) infection and bird (host) diversity in the eastern US. We constructed a novel geospatial contrasts analysis that compares the small differences in avian diversity of neighboring US counties (where one county reported human cases of WNV and the other reported no cases) with associated between-county differences in human disease. We also controlled for confounding factors of climate, regional variation in mosquito vector type, urbanization, and human socioeconomic factors that are all likely to affect human disease incidence. We found there is lower incidence of human WNV in eastern US counties that have greater avian (viral host) diversity. This pattern exists when examining diversity-disease relationships both before WNV reached the US (in 1998) and once the epidemic was underway (in 2002). The robust disease-diversity relationships confirm that the dilution effect can be observed in another emerging infectious disease and illustrate an important ecosystem service provided by biodiversity, further supporting the growing view that protecting biodiversity should be considered in public health and safety plans.     

2006～2008年我院法定报告传染病疫情分析

目的了解鹰潭市人民医院法定传染病报告情况,分析其流行病学特点,为制定传染病防治对策及降低传染病的发生提供科学依据。方法对鹰潭市人民医院2006～2008年法定传染病疫情资料进行分析．结果共报告法定传染病19种,累计报告发病4170例,其中无甲类传染病报告。主要病种为感染性腹泻、肺结核、病毒性肝炎、流行性腮腺炎、菌痢,占报告总数的93．62％;死亡13例（5个病种）．结论肺结核、乙型肝炎、肠道传染病是今后传染病防治工作的重点和难点,应加大管理力度．做好传染病的预防和控制工作．