Spillover: the role of bats and relationships as reservoirs of zoonotic viruses and the origin of new coronaviruses

AbstractEmerging infectious diseases arising from pathogen spillover from mammals to humans comprise a substantial health threat. Tracing virus origin and predicting the most likely host species for future spillover events are major objectives in One Health disciplines. However, the species that share pathogens most widely with other mammals, and the role of different wildlife groups in sharing viruses with humans remain poorly identified. To address this challenge, we applied network analysis and Bayesian hierarchical models to a global database of mammal-virus associations. We show that domesticated mammals and some primates hold the most central positions in networks of known mammal-virus associations. We revealed strong evidence that DNA viruses were phylogenetically more host specific than RNA viruses, while the frequencies of sharing viruses among hosts and the proportion of zoonotic viruses in hosts were larger for RNA than DNA viruses. Among entire host-virus networks, Carnivora and Chiroptera hold central positions for mainly sharing RNA viruses with other host species, while network centrality of Primates scored relatively high for sharing DNA viruses. Ungulates hold central positions for sharing both RNA and DNA viruses. Acknowledging the role of domestic species in addition to host and virus traits in patterns of virus sharing is necessary to improve our understanding of virus spread and spillover in times of global change.

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No Evidence of Coronaviruses or Other Potentially Zoonotic Viruses in Sunda pangolins (Manis javanica) Entering the Wildlife Trade via Malaysia

EcoHealth ◽

10.1007/s10393-020-01503-x ◽

2020 ◽

Vol 17 (3) ◽

pp. 406-418 ◽

Cited By ~ 1

Author(s):

Jimmy Lee ◽

Tom Hughes ◽

Mei-Ho Lee ◽

Hume Field ◽

Jeffrine Japning Rovie-Ryan ◽

...

Keyword(s):

Global Economy ◽

Peninsular Malaysia ◽

Wildlife Trade ◽

Total Nucleic Acid ◽

Molecular Screening ◽

Conventional Pcr ◽

Zoonotic Viruses ◽

Manis Javanica ◽

Livestock Health

AbstractThe legal and illegal trade in wildlife for food, medicine and other products is a globally significant threat to biodiversity that is also responsible for the emergence of pathogens that threaten human and livestock health and our global economy. Trade in wildlife likely played a role in the origin of COVID-19, and viruses closely related to SARS-CoV-2 have been identified in bats and pangolins, both traded widely. To investigate the possible role of pangolins as a source of potential zoonoses, we collected throat and rectal swabs from 334 Sunda pangolins (Manis javanica) confiscated in Peninsular Malaysia and Sabah between August 2009 and March 2019. Total nucleic acid was extracted for viral molecular screening using conventional PCR protocols used to routinely identify known and novel viruses in extensive prior sampling (> 50,000 mammals). No sample yielded a positive PCR result for any of the targeted viral families—Coronaviridae, Filoviridae, Flaviviridae, Orthomyxoviridae and Paramyxoviridae. In the light of recent reports of coronaviruses including a SARS-CoV-2-related virus in Sunda pangolins in China, the lack of any coronavirus detection in our ‘upstream’ market chain samples suggests that these detections in ‘downstream’ animals more plausibly reflect exposure to infected humans, wildlife or other animals within the wildlife trade network. While confirmatory serologic studies are needed, it is likely that Sunda pangolins are incidental hosts of coronaviruses. Our findings further support the importance of ending the trade in wildlife globally.

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Persistence of Multiple Paramyxoviruses in a Closed Captive Colony of Fruit Bats (Eidolon helvum)

Viruses ◽

10.3390/v13081659 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1659 ◽

Cited By ~ 1

Author(s):

Louise Gibson ◽

Maria Puig Ribas ◽

James Kemp ◽

Olivier Restif ◽

Richard D. Suu-Ire ◽

...

Keyword(s):

Urban Areas ◽

Emerging Diseases ◽

Fruit Bats ◽

Fatal Disease ◽

Zoonotic Viruses ◽

High Incidence ◽

Natural Hosts ◽

Free Ranging ◽

Eidolon Helvum

Bats have been identified as the natural hosts of several emerging zoonotic viruses, including paramyxoviruses, such as Hendra and Nipah viruses, that can cause fatal disease in humans. Recently, African fruit bats with populations that roost in or near urban areas have been shown to harbour a great diversity of paramyxoviruses, posing potential spillover risks to public health. Understanding the circulation of these viruses in their reservoir populations is essential to predict and prevent future emerging diseases. Here, we identify a high incidence of multiple paramyxoviruses in urine samples collected from a closed captive colony of circa 115 straw-coloured fruit bats (Eidolon helvum). The sequences detected have high nucleotide identities with those derived from free ranging African fruit bats and form phylogenetic clusters with the Henipavirus genus, Pararubulavirus genus and other unclassified paramyxoviruses. As this colony had been closed for 5 years prior to this study, these results indicate that within-host paramyxoviral persistence underlies the role of bats as reservoirs of these viruses.

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Persistence of Multiple Paramyxoviruses in a Closed Captive Colony of Fruit Bats (Eidolon helvum)

10.20944/preprints202107.0461.v1 ◽

2021 ◽

Author(s):

Louise Gibson ◽

Maria Puig Rebas ◽

James Kemp ◽

Olivier Restif ◽

Richard D. Suu-Ire ◽

...

Keyword(s):

Urban Areas ◽

Emerging Diseases ◽

Fruit Bats ◽

Fatal Disease ◽

Zoonotic Viruses ◽

High Incidence ◽

Natural Hosts ◽

Free Ranging ◽

Eidolon Helvum

Bats have been identified as the natural hosts of several emerging zoonotic viruses, including paramyxoviruses, such as Hendra and Nipah viruses, that can cause fatal disease in humans. Recently, African fruit bats with populations that roost in or near urban areas have been shown to harbour a great diversity of paramyxoviruses, posing potential spillover risks to public health. Understanding the circulation of these viruses in their reservoir populations is essential to predict and prevent future emerging diseases. Here, we identify a high incidence of multiple paramyxoviruses in urine samples collected from a closed, captive colony of circa. 115 straw-coloured fruit bats (Eidolon helvum). The sequences detected have high nucleotide identities with those derived from free ranging African fruit bats and form phylogenetic clusters with the Henipavirus genus, Pararubulavirus genus and other unclassified paramyxoviruses. As this colony had been closed for 5 years prior to this study, these results indicate that within-host paramyxoviral persistence underlies the role of bats as reservoirs of these viruses.

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Viral Metagenomic Analysis of Aedes albopictus Mosquitos from Southern Switzerland

Viruses ◽

10.3390/v12090929 ◽

2020 ◽

Vol 12 (9) ◽

pp. 929 ◽

Cited By ~ 2

Author(s):

Jakub Kubacki ◽

Eleonora Flacio ◽

Weihong Qi ◽

Valeria Guidi ◽

Mauro Tonolla ◽

...

Keyword(s):

Aedes Albopictus ◽

Complete Genome ◽

Potential Role ◽

Metagenomic Analysis ◽

Zoonotic Viruses ◽

Pathogenic Viruses ◽

Metagenomic Study ◽

Aedes Flavivirus ◽

Local Transmission

A metagenomic study was performed on 498 female and 40 male Aedes albopictus mosquitos collected in August and September 2019 in Ticino, a region in southern Switzerland, to address the question regarding the risk of the local transmission of zoonotic viruses. A total of 13 viruses from seven different virus families and several unclassified viral taxa were identified. Reads of insect-specific flaviviruses were present in all pools, and a complete genome of aedes flavivirus was assembled and phylogenetically analysed. The most abundant virus was Wenzhou sobemo-like virus, assembled from 1.3 × 105 to 3.6 × 106 reads in each pool. In a pool of male mosquitos, a complete genome of aedes Iflavi-like virus was detected and phylogenetically analysed. Most importantly, genomes of human pathogenic viruses were not found. This is the first study to determine the virome of Ae. albopictus from Switzerland and forms a baseline for future longitudinal investigations concerning the potential role of Ae. albopictus as a vector of clinically relevant viruses.

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The Potential Role of Endogenous Viral Elements in the Evolution of Bats as Reservoirs for Zoonotic Viruses

Annual Review of Virology ◽

10.1146/annurev-virology-092818-015613 ◽

2020 ◽

Vol 7 (1) ◽

pp. 103-119 ◽

Cited By ~ 3

Author(s):

Emilia C. Skirmuntt ◽

Marina Escalera-Zamudio ◽

Emma C. Teeling ◽

Adrian Smith ◽

Aris Katzourakis

Keyword(s):

Immune System ◽

Genome Size ◽

Potential Role ◽

Endogenous Retroviruses ◽

Small Genome ◽

Zoonotic Viruses ◽

Endogenous Viruses ◽

Foamy Viruses ◽

Endogenous Viral Elements

Despite a small genome size, bats have comparable diversity of retroviral and non-retroviral endogenous sequences to other mammals. These include Class I and Class II retroviral sequences, foamy viruses, and deltaretroviruses, as well as filovirus, bornavirus, and parvovirus endogenous viral elements. Some of these endogenous viruses are sufficiently preserved in bat genomes to be expressed, with potential effects for host biology. It is clear that the bat immune system differs when compared with other mammals, yet the role that virus-derived endogenous elements may have played in the evolution of bat immunity is poorly understood. In this review, we discuss some of the bat-specific immune mechanisms that may have resulted in a virus-tolerant phenotype and link these to the long-standing virus-host coevolution that may have allowed a large diversity of endogenous retroviruses and other endogenous viral elements to colonize bat genomes. We also consider the possible effects of endogenization in the evolution of the bat immune system.

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Detection of Hepatitis E Virus in Hyalomma lusitanicum Ticks Feeding on Wild Boars

Frontiers in Microbiology ◽

10.3389/fmicb.2021.692147 ◽

2021 ◽

Vol 12 ◽

Author(s):

Antonio Rivero-Juarez ◽

María A. Risalde ◽

Christian Gortázar ◽

Pedro Lopez-Lopez ◽

Jose A. Barasona ◽

...

Keyword(s):

Wild Boar ◽

Hepatitis E Virus ◽

Hepatitis E ◽

Cross Sectional Study ◽

Serum Samples ◽

Cross Sectional ◽

Wild Boars ◽

Zoonotic Viruses ◽

First Time

Little is known about the role of ticks in maintaining highly prevalent zoonotic viruses in wildlife, such as hepatitis E virus (HEV), which do not require ticks for transmission between animals and humans. In this cross-sectional study, adult female ticks were collected from Eurasian wild boar (Sus scrofa) in autumn 2015 in Spain. HEV RNA in both ticks and wild boar was evaluated by RT-qPCR. Twenty-nine adult Hyalomma lusitanicum ticks were collected from 29 wild boars. HEV RNA was detected in a total of 10 tick (34.4%) and 11 wild boar serum samples (37.9%). In two cases, detectable HEV RNA was found in a wild boar but not in the tick collected from them. In contrast, one HEV-positive tick was collected from an HEV-negative wild boar. All viral sequences were consistent with genotype 3f. We describe for the first time the presence of HEV RNA in adult Hyalomma lusitanicum ticks.

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No evidence of coronaviruses or other potentially zoonotic viruses in Sunda pangolins (Manis javanica) entering the wildlife trade via Malaysia

10.1101/2020.06.19.158717 ◽

2020 ◽

Cited By ~ 8

Author(s):

Jimmy Lee ◽

Tom Hughes ◽

Mei-Ho Lee ◽

Hume Field ◽

Jeffrine Japning Rovie-Ryan ◽

...

Keyword(s):

Global Economy ◽

Peninsular Malaysia ◽

Wildlife Trade ◽

Total Nucleic Acid ◽

Molecular Screening ◽

Conventional Pcr ◽

Zoonotic Viruses ◽

Manis Javanica ◽

Livestock Health

AbstractThe legal and illegal trade in wildlife for food, medicine and other products is a globally significant threat to biodiversity that is also responsible for the emergence of pathogens that threaten human and livestock health and our global economy. Trade in wildlife likely played a role in the origin of COVID-19, and viruses closely related to SARS-CoV-2 have been identified in bats and pangolins, both traded widely. To investigate the possible role of pangolins as a source of potential zoonoses, we collected throat and rectal swabs from 334 Sunda pangolins (Manis javanica) confiscated in Peninsular Malaysia and Sabah between August 2009 and March 2019. Total nucleic acid was extracted for viral molecular screening using conventional PCR protocols used to routinely identify known and novel viruses in extensive prior sampling (>50,000 mammals). No sample yielded a positive PCR result for any of the targeted viral families – Coronaviridae, Filoviridae, Flaviviridae, Orthomyxoviridae and Paramyxoviridae. In light of recent reports of coronaviruses including a SARS-CoV-2 related virus in Sunda pangolins in China, the lack of any coronavirus detection in our ‘upstream’ market chain samples suggests that these detections in ‘downstream’ animals more plausibly reflect exposure to infected humans, wildlife or other animals within the wildlife trade network. While confirmatory serologic studies are needed, it is likely that Sunda pangolins are incidental hosts of coronaviruses. Our findings further support the importance of ending the trade in wildlife globally.

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A world of viruses nested within parasites: Unraveling viral diversity within parasitic flatworms (Platyhelminthes)

10.1101/2021.12.15.472606 ◽

2021 ◽

Author(s):

Nolwenn M Dheilly ◽

Yannick Blanchard ◽

Karyna Rosario ◽

Pierrick Lucas

Keyword(s):

Phylogenetic Analyses ◽

Blood Feeding ◽

Viral Reservoirs ◽

Free Living ◽

Host Shifts ◽

Zoonotic Viruses ◽

Need To Evaluate ◽

Parasitic Lifestyle ◽

Viral Sequences

Because parasites have an inextricable relationship with their host, they have the potential to serve as viral reservoirs or facilitate virus host-shifts. Yet, little is known about viruses infecting parasitic hosts except for blood-feeding arthropods that are well-known vectors of zoonotic viruses. Herein we uncover viruses of flatworms (Phylum Platyhelminthes, group Neodermata) that specialize in parasitizing vertebrates and their ancestral free-living relatives. We discovered 115 novel viral sequences, including 1 in Macrostomorpha, 5 in Polycladida, 44 in Tricladida, 1 in Monogenea, 15 in Cestoda and 49 in Trematoda, through data mining. The majority of newly identified viruses constitute novel families or genera. Phylogenetic analyses show that the virome of flatworms changed dramatically during the transition of Neodermatans to a parasitic lifestyle. Most Neodermatan viruses seem to co-diversify with their host , with the exception of rhabdoviruses which may switch host more often, based on phylogenetic relationships. Neodermatan rhabodviruses also have an ancestral position to vertebrate-associated viruses, including Lyssaviruses, suggesting that vertebrate rhabdoviruses emerged from a flatworm rhabdovirus in a parasitized host. This study reveals an extensive diversity of viruses in Platyhelminthes and highlights the need to evaluate the role of viral infection in flatworm-associated diseases.

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Role of dactinomycin in the improved survival of children with Wilms' tumor

JAMA ◽

10.1001/jama.195.12.1005 ◽

1966 ◽

Vol 195 (12) ◽

pp. 1005-1009 ◽

Cited By ~ 18

Author(s):

D. J. Fernbach

Keyword(s):

Wilms Tumor

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