Morse S.S.,Columbia University |
Morse S.S.,University of California at Davis |
Mazet J.A.K.,University of California at Davis |
Woolhouse M.,University of Edinburgh |
And 7 more authors.
The Lancet | Year: 2012
Most pandemics-eg, HIV/AIDS, severe acute respiratory syndrome, pandemic influenza-originate in animals, are caused by viruses, and are driven to emerge by ecological, behavioural, or socioeconomic changes. Despite their substantial effects on global public health and growing understanding of the process by which they emerge, no pandemic has been predicted before infecting human beings. We review what is known about the pathogens that emerge, the hosts that they originate in, and the factors that drive their emergence. We discuss challenges to their control and new efforts to predict pandemics, target surveillance to the most crucial interfaces, and identify prevention strategies. New mathematical modelling, diagnostic, communications, and informatics technologies can identify and report hitherto unknown microbes in other species, and thus new risk assessment approaches are needed to identify microbes most likely to cause human disease. We lay out a series of research and surveillance opportunities and goals that could help to overcome these challenges and move the global pandemic strategy from response to pre-emption.
Zhu Q.,State University of New York at Buffalo |
Kosoy M.,Centers for Disease Control and Prevention |
Olival K.J.,EcoHealth Alliance |
Dittmar K.,State University of New York at Buffalo
Genome biology and evolution | Year: 2014
Bartonellae are mammalian pathogens vectored by blood-feeding arthropods. Although of increasing medical importance, little is known about their ecological past, and host associations are underexplored. Previous studies suggest an influence of horizontal gene transfers in ecological niche colonization by acquisition of host pathogenicity genes. We here expand these analyses to metabolic pathways of 28 Bartonella genomes, and experimentally explore the distribution of bartonellae in 21 species of blood-feeding arthropods. Across genomes, repeated gene losses and horizontal gains in the phospholipid pathway were found. The evolutionary timing of these patterns suggests functional consequences likely leading to an early intracellular lifestyle for stem bartonellae. Comparative phylogenomic analyses discover three independent lineage-specific reacquisitions of a core metabolic gene-NAD(P)H-dependent glycerol-3-phosphate dehydrogenase (gpsA)-from Gammaproteobacteria and Epsilonproteobacteria. Transferred genes are significantly closely related to invertebrate Arsenophonus-, and Serratia-like endosymbionts, and mammalian Helicobacter-like pathogens, supporting a cellular association with arthropods and mammals at the base of extant Bartonella spp. Our studies suggest that the horizontal reacquisitions had a key impact on bartonellae lineage specific ecological and functional evolution. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
Keesing F.,Bard College |
Belden L.K.,Virginia Polytechnic Institute and State University |
Daszak P.,EcoHealth Alliance |
Dobson A.,Princeton University |
And 9 more authors.
Nature | Year: 2010
Current unprecedented declines in biodiversity reduce the ability of ecological communities to provide many fundamental ecosystem services. Here we evaluate evidence that reduced biodiversity affects the transmission of infectious diseases of humans, other animals and plants. In principle, loss of biodiversity could either increase or decrease disease transmission. However, mounting evidence indicates that biodiversity loss frequently increases disease transmission. In contrast, areas of naturally high biodiversity may serve as a source pool for new pathogens. Overall, despite many remaining questions, current evidence indicates that preserving intact ecosystems and their endemic biodiversity should generally reduce the prevalence of infectious diseases. © 2010 Macmillan Publishers Limited. All rights reserved.
Olival K.J.,EcoHealth Alliance
Emerging infectious diseases | Year: 2013
To determine geographic range for Ebola virus, we tested 276 bats in Bangladesh. Five (3.5%) bats were positive for antibodies against Ebola Zaire and Reston viruses; no virus was detected by PCR. These bats might be a reservoir for Ebola or Ebola-like viruses, and extend the range of filoviruses to mainland Asia.
Preston N.D.,EcoHealth Alliance |
Daszak P.,EcoHealth Alliance |
Colwell R.R.,University of Maryland University College
Current Topics in Microbiology and Immunology | Year: 2013
One Health approaches have tended to focus on closer collaboration among veterinarians and medical professionals, but remain unclear about how ecological approaches could be applied or how they might benefit public health and disease control. In this chapter, we review ecological concepts, and discuss their relevance to health, with an emphasis on emerging infectious diseases (EIDs). Despite the fact that most EIDs originate in wildlife, few studies account for the population, community, or ecosystem ecology of the host, reservoir, or vector. The dimensions of ecological approaches to public health that we propose in this chapter are, in essence, networks of population dynamics, community structure, and ecosystem matrices incorporating concepts of complexity, resilience, and biogeochemical processes. © Springer-Verlag Berlin Heidelberg 2013.
Mandl J.N.,U.S. National Institutes of Health |
Mandl J.N.,McGill University |
Ahmed R.,Emory University |
Barreiro L.B.,University of Montréal |
And 4 more authors.
Cell | Year: 2015
Zoonotic viruses, such as HIV, Ebola virus, coronaviruses, influenza A viruses, hantaviruses, or henipaviruses, can result in profound pathology in humans. In contrast, populations of the reservoir hosts of zoonotic pathogens often appear to tolerate these infections with little evidence of disease. Why are viruses more dangerous in one species than another? Immunological studies investigating quantitative and qualitative differences in the host-virus equilibrium in animal reservoirs will be key to answering this question, informing new approaches for treating and preventing zoonotic diseases. Integrating an understanding of host immune responses with epidemiological, ecological, and evolutionary insights into viral emergence will shed light on mechanisms that minimize fitness costs associated with viral infection, facilitate transmission to other hosts, and underlie the association of specific reservoir hosts with multiple emerging viruses. Reservoir host studies provide a rich opportunity for elucidating fundamental immunological processes and their underlying genetic basis, in the context of distinct physiological and metabolic constraints that contribute to host resistance and disease tolerance. © 2015 Elsevier Inc. All rights reserved.
Murray K.A.,EcoHealth Alliance |
Verde Arregoitia L.D.,University of Queensland |
Davidson A.,State University of New York at Stony Brook |
Di Marco M.,University of Rome La Sapienza |
Di Fonzo M.M.I.,University of Queensland
Global Change Biology | Year: 2014
Comparative extinction risk analysis is a common approach for assessing the relative plight of biodiversity and making conservation recommendations. However, the usefulness of such analyses for conservation practice has been questioned. One reason for underperformance may be that threats arising from global environmental changes (e.g., habitat loss, invasive species, climate change) are often overlooked, despite being widely regarded as proximal drivers of species' endangerment. We explore this problem by (i) reviewing the use of threats in this field and (ii) quantitatively investigating the effects of threat exclusion on the interpretation and potential application of extinction risk model results. We show that threat variables are routinely (59%) identified as significant predictors of extinction risk, yet while most studies (78%) include extrinsic factors of some kind (e.g., geographic or bioclimatic information), the majority (63%) do not include threats. Despite low overall usage, studies are increasingly employing threats to explain patterns of extinction risk. However, most continue to employ methods developed for the analysis of heritable traits (e.g., body size, fecundity), which may be poorly suited to the treatment of nonheritable predictors including threats. In our global mammal and continental amphibian extinction risk case studies, omitting threats reduced model predictive performance, but more importantly (i) reduced mechanistic information relevant to management; (ii) resulted in considerable disagreement in species classifications (12% and 5% for amphibians and mammals, respectively, translating to dozens and hundreds of species); and (iii) caused even greater disagreement (20-60%) in a downstream conservation application (species ranking). We conclude that the use of threats in comparative extinction risk analysis is important and increasing but currently in the early stages of development. Priorities for future studies include improving uptake, availability, quality and quantification of threat data, and developing analytical methods that yield more robust, relevant and tangible products for conservation applications. © 2013 John Wiley & Sons Ltd.
Hosseini P.,EcoHealth Alliance
PloS one | Year: 2010
Controlling the pandemic spread of newly emerging diseases requires rapid, targeted allocation of limited resources among nations. Critical, early control steps would be greatly enhanced if the key risk factors can be identified that accurately predict early disease spread immediately after emergence. Here, we examine the role of travel, trade, and national healthcare resources in predicting the emergence and initial spread of 2009 A/H1N1 influenza. We find that incorporating national healthcare resource data into our analyses allowed a much greater capacity to predict the international spread of this virus. In countries with lower healthcare resources, the reporting of 2009 A/H1N1 cases was significantly delayed, likely reflecting a lower capacity for testing and reporting, as well as other socio-political issues. We also report substantial international trade in live swine and poultry in the decade preceding the pandemic which may have contributed to the emergence and mixed genotype of this pandemic strain. However, the lack of knowledge of recent evolution of each H1N1 viral gene segment precludes the use of this approach to determine viral origins. We conclude that strategies to prevent pandemic influenza virus emergence and spread in the future should include: 1) enhanced surveillance for strains resulting from reassortment in traded livestock; 2) rapid deployment of control measures in the initial spreading phase to countries where travel data predict the pathogen will reach and to countries where lower healthcare resources will likely cause delays in reporting. Our results highlight the benefits, for all parties, when higher income countries provide additional healthcare resources for lower income countries, particularly those that have high air traffic volumes. In particular, international authorities should prioritize aid to those poorest countries where both the risk of emerging infectious diseases and air traffic volume is highest. This strategy will result in earlier detection of pathogens and a reduction in the impact of future pandemics.
Olival K.J.,EcoHealth Alliance |
Hayman D.T.S.,Colorado State University |
Hayman D.T.S.,University of Florida |
Hayman D.T.S.,Massey University
Viruses | Year: 2014
Filoviruses, including Ebolavirus and Marburgvirus, pose significant threats to public health and species conservation by causing hemorrhagic fever outbreaks with high mortality rates. Since the first outbreak in 1967, their origins, natural history, and ecology remained elusive until recent studies linked them through molecular, serological, and virological studies to bats. We review the ecology, epidemiology, and natural history of these systems, drawing on examples from other bat-borne zoonoses, and highlight key areas for future research. We compare and contrast results from ecological and virological studies of bats and filoviruses with those of other systems. We also highlight how advanced methods, such as more recent serological assays, can be interlinked with flexible statistical methods and experimental studies to inform the field studies necessary to understand filovirus persistence in wildlife populations and cross-species transmission leading to outbreaks. We highlight the need for a more unified, global surveillance strategy for filoviruses in wildlife, and advocate for more integrated, multi-disciplinary approaches to understand dynamics in bat populations to ultimately mitigate or prevent potentially devastating disease outbreaks. © 2014 by the authors; licensee MDPI, Basel, Switzerland.
Lei B.R.,EcoHealth Alliance |
Lei B.R.,Harvard University |
Olival K.J.,EcoHealth Alliance
PLoS Neglected Tropical Diseases | Year: 2014
Background:Emerging bacterial zoonoses in bats and rodents remain relatively understudied. We conduct the first comparative host-pathogen coevolutionary analyses of bacterial pathogens in these hosts, using Bartonella spp. and Leptospira spp. as a model.Methodology/Principal Findings:We used published genetic data for 51 Bartonella genotypes from 24 bat species, 129 Bartonella from 38 rodents, and 26 Leptospira from 20 bats. We generated maximum likelihood and Bayesian phylogenies for hosts and bacteria, and tested for coevoutionary congruence using programs ParaFit, PACO, and Jane. Bartonella spp. and their bat hosts had a significant coevolutionary fit (ParaFitGlobal = 1.9703, P≤0.001; m2 global value = 7.3320, P≤0.0001). Bartonella spp. and rodent hosts also indicated strong overall patterns of cospeciation (ParaFitGlobal = 102.4409, P≤0.001; m2 global value = 86.532, P≤0.0001). In contrast, we were unable to reject independence of speciation events in Leptospira and bats (ParaFitGlobal = 0.0042, P = 0.84; m2 global value = 4.6310, P = 0.5629). Separate analyses of New World and Old World data subsets yielded results congruent with analysis from entire datasets. We also conducted event-based cophylogeny analyses to reconstruct likely evolutionary histories for each group of pathogens and hosts. Leptospira and bats had the greatest number of host switches per parasite (0.731), while Bartonella and rodents had the fewest (0.264).Conclusions/Significance:In both bat and rodent hosts, Bartonella exhibits significant coevolution with minimal host switching, while Leptospira in bats lacks evolutionary congruence with its host and has high number of host switches. Reasons underlying these variable coevolutionary patterns in host range are likely due to differences in disease-specific transmission and host ecology. Understanding the coevolutionary patterns and frequency of host-switching events between bacterial pathogens and their hosts will allow better prediction of spillover between mammal reservoirs, and ultimately to humans. © 2014 Lei, Olival.