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Proceedings of the National Academy of... Mar 2020Disease outbreaks and pathogen introductions can have significant effects on host populations, and the ability of pathogens to persist in the environment can exacerbate...
Disease outbreaks and pathogen introductions can have significant effects on host populations, and the ability of pathogens to persist in the environment can exacerbate disease impacts by fueling sustained transmission, seasonal epidemics, and repeated spillover events. While theory suggests that the presence of an environmental reservoir increases the risk of host declines and threat of extinction, the influence of reservoir dynamics on transmission and population impacts remains poorly described. Here we show that the extent of the environmental reservoir explains broad patterns of host infection and the severity of disease impacts of a virulent pathogen. We examined reservoir and host infection dynamics and the resulting impacts of , the fungal pathogen that causes white-nose syndrome, in 39 species of bats at 101 sites across the globe. Lower levels of pathogen in the environment consistently corresponded to delayed infection of hosts, fewer and less severe infections, and reduced population impacts. In contrast, an extensive and persistent environmental reservoir led to early and widespread infections and severe population declines. These results suggest that continental differences in the persistence or decay of in the environment altered infection patterns in bats and influenced whether host populations were stable or experienced severe declines from this disease. Quantifying the impact of the environmental reservoir on disease dynamics can provide specific targets for reducing pathogen levels in the environment to prevent or control future epidemics.
Topics: Animals; Ascomycota; Chiroptera; Disease Reservoirs; Epidemics; Hibernation; Mycoses; Nose; Nose Diseases; Population Dynamics; Seasons
PubMed: 32179668
DOI: 10.1073/pnas.1914794117 -
Comparative Immunology, Microbiology... Jul 2009
Topics: Animals; Birds; Communicable Diseases; Disease Outbreaks; Disease Reservoirs; Humans; Influenza in Birds; Influenza, Human
PubMed: 18455796
DOI: 10.1016/j.cimid.2008.01.008 -
Emerging Infectious Diseases May 2014Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats... (Review)
Review
Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host-virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts.
Topics: Animals; Biological Evolution; Body Temperature; Chiroptera; Disease Reservoirs; Fever; Flight, Animal; Host-Pathogen Interactions; Humans; Zoonoses
PubMed: 24750692
DOI: 10.3201/eid2005.130539 -
Proceedings of the National Academy of... Apr 2022SignificanceThe clear need to mitigate zoonotic risk has fueled increased viral discovery in specific reservoir host taxa. We show that a combination of viral and...
SignificanceThe clear need to mitigate zoonotic risk has fueled increased viral discovery in specific reservoir host taxa. We show that a combination of viral and reservoir traits can predict zoonotic virus virulence and transmissibility in humans, supporting the hypothesis that bats harbor exceptionally virulent zoonoses. However, pandemic prevention requires thinking beyond zoonotic capacity, virulence, and transmissibility to consider collective "burden" on human health. For this, viral discovery targeting specific reservoirs may be inefficient as death burden correlates with viral, not reservoir, traits, and depends on context-specific epidemiological dynamics across and beyond the human-animal interface. These findings suggest that longitudinal studies of viral dynamics in reservoir and spillover host populations may offer the most effective strategy for mitigating zoonotic risk.
Topics: Animals; Chiroptera; Disease Reservoirs; Virulence; Viruses; Zoonoses
PubMed: 35349342
DOI: 10.1073/pnas.2113628119 -
Philosophical Transactions of the Royal... Sep 2019The risk of zoonotic spillover from reservoir hosts, such as wildlife or domestic livestock, to people is shaped by the spatial and temporal distribution of infection in... (Review)
Review
The risk of zoonotic spillover from reservoir hosts, such as wildlife or domestic livestock, to people is shaped by the spatial and temporal distribution of infection in reservoir populations. Quantifying these distributions is a key challenge in epidemiology and disease ecology that requires researchers to make trade-offs between the extent and intensity of spatial versus temporal sampling. We discuss sampling methods that strengthen the reliability and validity of inferences about the dynamics of zoonotic pathogens in wildlife hosts. This article is part of the theme issue 'Dynamic and integrative approaches to understanding pathogen spillover'.
Topics: Animals; Animals, Wild; Disease Reservoirs; Epidemiological Monitoring; Population Surveillance; Reproducibility of Results; Zoonoses
PubMed: 31401966
DOI: 10.1098/rstb.2018.0336 -
Emerging Infectious Diseases Jul 2007Thottapalayam virus (TPMV) has been placed in the genus Hantavirus of the family Bunyaviridae by virtue of its morphologic features and overall genetic similarities to... (Review)
Review
Thottapalayam virus (TPMV) has been placed in the genus Hantavirus of the family Bunyaviridae by virtue of its morphologic features and overall genetic similarities to well-characterized rodentborne hantaviruses. This virus has been isolated from the Asian house shrew (Suncus murinus); however, whether TPMV is naturally harbored by an insectivore host or represents spillover from a rodent reservoir host is unknown. Our analysis of published and unpublished data on the experimental host range, genetics, and molecular phylogeny of TPMV supports coevolution of TPMV with its nonrodent reservoir host. Future studies on the epizootiology of TPMV and investigations of new shrewborne hantaviruses will provide additional insights into the evolutionary origin of hantaviruses in their rodent and insectivore reservoir hosts. Such investigations may also provide clues about determinants of hantavirus pathogenicity and virulence.
Topics: Animals; Disease Reservoirs; Genetic Variation; Orthohantavirus; Hantavirus Infections; Humans; Phylogeny; Shrews; Virulence
PubMed: 18214168
DOI: 10.3201/eid1307.070031 -
Philosophical Transactions of the Royal... Sep 2009Foot-and-mouth disease can be controlled by zoo-sanitary measures and vaccination but this is difficult owing to the existence of multiple serotypes of the causative... (Review)
Review
Foot-and-mouth disease can be controlled by zoo-sanitary measures and vaccination but this is difficult owing to the existence of multiple serotypes of the causative virus, multiple host species including wildlife and extreme contagiousness. Although intolerable to modern high-production livestock systems, the disease is not usually fatal and often not a priority for control in many developing countries, which remain reservoirs for viral dissemination. Phylogenetic analysis of the viruses circulating worldwide reveals seven principal reservoirs, each requiring a tailored regional control strategy. Considerable trade benefits accrue to countries that eradicate the disease but as well as requiring regional cooperation, achieving and maintaining this status using current tools takes a great deal of time, money and effort. Therefore, a progressive approach is needed that can provide interim benefits along the pathway to final eradication. Research is needed to understand and predict the patterns of viral persistence and emergence and to improve vaccine selection. Better diagnostic methods and especially better vaccines could significantly improve control in both the free and the affected parts of the world. In particular, vaccines with improved thermostability and a longer duration of immunity would facilitate control and make it less reliant on advanced veterinary infrastructures.
Topics: Animals; Animals, Domestic; Developing Countries; Disease Reservoirs; Foot-and-Mouth Disease; Foot-and-Mouth Disease Virus; Viral Vaccines
PubMed: 19687036
DOI: 10.1098/rstb.2009.0100 -
Parasitology Apr 2018Leptospirosis is a zoonotic bacterial disease of global importance. A large spectrum of asymptomatic animal hosts can carry the infection and contribute to the burden of... (Review)
Review
Leptospirosis is a zoonotic bacterial disease of global importance. A large spectrum of asymptomatic animal hosts can carry the infection and contribute to the burden of human disease. Environmental sources of human contamination also point to the importance of a hydrotelluric reservoir. Leptospirosis can be caused by as many as 15 different pathogenic or intermediate Leptospira species. However, classification of these bacteria remains complicated through the use of both serological and genetic classification systems that show poor correlation. With the advent of molecular techniques, DNA-based barcoding offers a conceptual framework that can be used for leptospirosis surveillance as well as source tracking. In this review, we summarize some of the current techniques, highlight significant successes and weaknesses and point to the future opportunities and challenges to successfully establish a widely applicable barcoding scheme for Leptospira.
Topics: Animals; DNA Barcoding, Taxonomic; Disease Reservoirs; Environmental Microbiology; Genotyping Techniques; Humans; Leptospira; Leptospirosis; Phylogeny; Zoonoses
PubMed: 28716157
DOI: 10.1017/S0031182017001147 -
Current Opinion in Virology Feb 2019Hepatitis E virus (HEV) infects both humans and other animal species. Recently, we have seen a steady increase in autochthonous cases of human HEV infection in certain... (Review)
Review
Hepatitis E virus (HEV) infects both humans and other animal species. Recently, we have seen a steady increase in autochthonous cases of human HEV infection in certain areas especially in Europe, and large outbreaks in several African countries among the displaced population. This mini-review critically analyzes potential host, environmental, and viral factors that may be associated with the emergence of hepatitis E in humans. The existence of numerous HEV reservoir animals such as pig, deer and rabbit results in human exposure to infected animals via direct contact or through animal meat consumption. Contamination of drinking, irrigation and coastal water by animal and human wastes lead to emergence of endemic cases in industrialized countries and outbreaks in displaced communities especially in war-torn countries.
Topics: Animals; Communicable Diseases, Emerging; Disease Outbreaks; Disease Reservoirs; Hepatitis E; Hepatitis E virus; Humans; Meat; Point Mutation; Recombination, Genetic; Swine; Zoonoses
PubMed: 30497051
DOI: 10.1016/j.coviro.2018.11.006 -
Veterinary Research Feb 2012Numerous mammal species, including domestic and wild animals such as ruminants, dogs, cats and rodents, as well as humans, serve as reservoir hosts for various... (Review)
Review
Numerous mammal species, including domestic and wild animals such as ruminants, dogs, cats and rodents, as well as humans, serve as reservoir hosts for various Bartonella species. Some of those species that exploit non-human mammals as reservoir hosts have zoonotic potential. Our understanding of interactions between bartonellae and reservoir hosts has been greatly improved by the development of animal models for infection and the use of molecular tools allowing large scale mutagenesis of Bartonella species. By reviewing and combining the results of these and other approaches we can obtain a comprehensive insight into the molecular interactions that underlie the exploitation of reservoir hosts by Bartonella species, particularly the well-studied interactions with vascular endothelial cells and erythrocytes.
Topics: Animals; Bartonella; Bartonella Infections; Disease Reservoirs; Endothelial Cells; Erythrocytes; Mammals
PubMed: 22369683
DOI: 10.1186/1297-9716-43-15