scholarly journals Mammal virus diversity estimates are unstable due to accelerating discovery effort

2022 ◽  
Vol 18 (1) ◽  
Author(s):  
Rory Gibb ◽  
Gregory F. Albery ◽  
Nardus Mollentze ◽  
Evan A. Eskew ◽  
Liam Brierley ◽  
...  
Keyword(s):  
Host Species ◽  
Current Knowledge ◽  
Current Data ◽  
Viral Diversity ◽  
Sampling Effort ◽  
Ecological Inference ◽  
Wild Mammals ◽  
Virus Diversity ◽  
Zoonotic Risk ◽  
Association Data

Host-virus association data underpin research into the distribution and eco-evolutionary correlates of viral diversity and zoonotic risk across host species. However, current knowledge of the wildlife virome is inherently constrained by historical discovery effort, and there are concerns that the reliability of ecological inference from host-virus data may be undermined by taxonomic and geographical sampling biases. Here, we evaluate whether current estimates of host-level viral diversity in wild mammals are stable enough to be considered biologically meaningful, by analysing a comprehensive dataset of discovery dates of 6571 unique mammal host-virus associations between 1930 and 2018. We show that virus discovery rates in mammal hosts are either constant or accelerating, with little evidence of declines towards viral richness asymptotes, even in highly sampled hosts. Consequently, inference of relative viral richness across host species has been unstable over time, particularly in bats, where intensified surveillance since the early 2000s caused a rapid rearrangement of species' ranked viral richness. Our results illustrate that comparative inference of host-level virus diversity across mammals is highly sensitive to even short-term changes in sampling effort. We advise caution to avoid overinterpreting patterns in current data, since it is feasible that an analysis conducted today could draw quite different conclusions than one conducted only a decade ago.

scholarly journals Mammal virus diversity estimates are unstable due to accelerating discovery effort

2021 ◽  
Author(s):  
Rory Gibb ◽  
Gregory F Albery ◽  
Nardus F Mollentze ◽  
Evan A Eskew ◽  
Liam Brierley ◽  
...  
Keyword(s):  
Current Data ◽  
Viral Diversity ◽  
Sampling Effort ◽  
Ecological Inference ◽  
Wild Mammals ◽  
Virus Diversity ◽  
Highly Sensitive ◽  
Zoonotic Risk ◽  
Association Data ◽  
Diversity Estimates

Host-virus association data form the backbone of research into eco-evolutionary drivers of viral diversity and host-level zoonotic risk. However, knowledge of the wildlife virome is inherently constrained by historical discovery effort, and there are concerns that the reliability of ecological inference from host-virus data may be undermined by taxonomic and geographical sampling biases. Here, we evaluate whether current estimates of host-level viral diversity in wild mammals are stable enough to be considered biologically meaningful, by analysing a comprehensive dataset of discovery dates of 6,571 unique mammal host-virus associations between 1930 and 2018. We show that virus discovery rates in mammal hosts are still either constant or accelerating, with little evidence of declines towards viral richness asymptotes in even highly-sampled hosts. Consequently, inference of relative viral richness across host species has been unstable over time, particularly in bats, where intensified surveillance since the early 2000s caused a rapid rearrangement of species' ranked viral richness. Our results show that comparative inference of host-level virus diversity across mammals is highly sensitive to even short-term changes in sampling effort. We advise caution to avoid overinterpreting patterns in current data, since our findings suggest that an analysis conducted today could feasibly draw quite different conclusions than one conducted only a decade ago.

Host species of mistletoes (Loranthaceae and Viscaceae) in Australia

2020 ◽  
Vol 68 (1) ◽  
pp. 1
Author(s):  
Nicole F. Clark ◽  
Jen A. McComb ◽  
Andrew W. Taylor-Robinson
Keyword(s):  
Alien Species ◽  
Host Species ◽  
Current Knowledge ◽  
Sampling Effort ◽  
New Host ◽  
Host Family ◽  
Single Host ◽  
New Hosts ◽  
Host Families ◽  
New Host Species

In order to study the relationships between mistletoes and their host species, comprehensive collections of both mistletoes and hosts are needed. The effect of sampling effort on the estimation of mistletoe host range was demonstrated in a comparison of an inventory of host mistletoe interactions published by Downey in 1998 and a 2019 inventory presented here, which is based on data from collections in the Australian Virtual Herbarium and information in the literature. New hosts were recorded for 93% of the 90 Australian mistletoes. There were 338 previously known hosts recorded to be parasitised by additional mistletoe species, and 317 new host species that were not previously known as mistletoe hosts (25 being alien species). These were from 78 new host genera and 13 new host families. The total number of host species was 1186 within 327 genera from 92 host families. A total of 63% of all Australian mistletoes parasitise species of either Eucalyptus or Acacia or both these genera. The large rise in host species recorded in less than two decades between inventories suggests that current knowledge of hosts is still incomplete, such that further new hosts will be discovered in future. Some mistletoe species show a strong preference to one host family or genus but due to insufficient collecting it is premature to conclude that any of the three species known from a single host are host specific.

Enzootic Activity of Chlamydia in Farms Located in a Hotspot Area for Zoonosis Emergence

2021 ◽  
Author(s):  
Ezequiel Andres Vanderhoeven ◽  
Jessica P. Mosmann ◽  
Adrián Díaz ◽  
Cecilia G. Cuffini
Keyword(s):  
Bird Species ◽  
Farm Animals ◽  
Economic Losses ◽  
Wild Mammals ◽  
Specific Pcr ◽  
Chlamydial Species ◽  
Zoonotic Risk ◽  
Two Samples ◽  
In The Wild ◽  
First Time

Abstract Chlamydias are obligated intracellular Gram-negative bacteria, considered important zoonotic pathogens, broadly present in several bird species and responsible for economic losses in animal production. We analyzed the presence of Chlamydial species with zoonotic risk in farm animals in a highly biodiverse area and with great human circulation, the Argentine, Brazil and Paraguay tri-border area. We surveyed nine farms in an area and nasally swabbed a total of 62 animals. DNA was extracted and specific PCR was performed to identify chlamydial species. We detected Chlamydia spp . in 6.5% (4/62) of the animals tested, positive samples belonged to cattle and none of them showed symptoms of respiratory disease nor had been diagnose with reproductive diseases. Specific nested PCR confirmed two samples belonged to C. pecorum and two to C. psittaci . We report for the first time Chlamydia circulation with zoonotic risk in the region. Surveys in birds and wild mammals could give a better understanding to know what Chlamydial species are circulating in the wild interface. The zoonotic potential should be taking into account as farm workers and the surrounding population could be silent carriers or have respiratory diseases being underdiagnosed, and therefore should be considered in the differential diagnoses.

scholarly journals What factors explain the geographical range of mammalian parasites?

2019 ◽  
Vol 286 (1903) ◽  
pp. 20190673 ◽  
Author(s):  
James E. Byers ◽  
J. P. Schmidt ◽  
Paula Pappalardo ◽  
Sarah E. Haas ◽  
Patrick R. Stephens
Keyword(s):  
Host Species ◽  
Parasite Species ◽  
Geographical Area ◽  
Complete Information ◽  
Sampling Effort ◽  
Free Living ◽  
Living Species ◽  
Habitat Breadth ◽  
Taxonomic Groups ◽  
Host Characteristics

Free-living species vary substantially in the extent of their spatial distributions. However, distributions of parasitic species have not been comprehensively compared in this context. We investigated which factors most influence the geographical extent of mammal parasites. Using the Global Mammal Parasite Database we analysed 17 818 individual geospatial records on 1806 parasite species (encompassing viruses, bacteria, protozoa, arthropods and helminths) that infect 396 carnivore, ungulate and primate host species. As a measure of the geographical extent of each parasite species we quantified the number and area of world ecoregions occupied by each. To evaluate the importance of variables influencing the summed area of ecoregions occupied by a parasite species, we used Bayesian network analysis of a subset ( n = 866) of the parasites in our database that had at least two host species and complete information on parasite traits. We found that parasites that covered more geographical area had a greater number of host species, higher average phylogenetic relatedness between host species and more sampling effort. Host and parasite taxonomic groups had weak and indirect effects on parasite ecoregion area; parasite transmission mode had virtually no effect. Mechanistically, a greater number of host species probably increases both the collective abundance and habitat breadth of hosts, providing more opportunities for a parasite to have an expansive range. Furthermore, even though mammals are one of the best-studied animal classes, the ecoregion area occupied by their parasites is strongly sensitive to sampling effort, implying mammal parasites are undersampled. Overall, our results support that parasite geographical extent is largely controlled by host characteristics, many of which are subsumed within host taxonomic identity.

Helminth parasites of wild Mexican mammals: list of species, hosts and geographical distribution

Zootaxa ◽  
2012 ◽  
Vol 3290 (1) ◽  
pp. 1 ◽  
Author(s):  
LUIS GARCÍA-PRIETO ◽  
JORGE FALCÓN-ORDAZ ◽  
CARMEN GUZMÁN-CORNEJO
Keyword(s):  
Geographical Distribution ◽  
Current Knowledge ◽  
Helminth Parasites ◽  
Wild Mammals ◽  
First Time

In the present work, a total of 339 nominal taxa of helminths (53 trematodes, 46 cestodes, 12 acanthocephalans, 227 nem-atodes, and 1 hirudinean), associated with 136 taxa of wild mammals from Mexico, are listed. Information on hosts, hab-itat, distribution, and records is included; these data come from 242 localities, pertaining to 31 of the 32 Mexican states,and represent the current knowledge on helminth parasites of wild mammals in Mexico. Eighteen taxa of helminths are registered for the first time in Mexico, and 46 new locality records are presented.

scholarly journals Dissecting the Formation Histories of Galaxies with Stellar Populations Models

2009 ◽  
Vol 5 (S262) ◽  
pp. 153-163
Author(s):  
Ivo Labbé
Keyword(s):  
Star Formation ◽  
Current Knowledge ◽  
High Redshift ◽  
Local Environment ◽  
Stellar Populations ◽  
Current Data ◽  
Star Formation History ◽  
Spectral Energy ◽  
Formation History ◽  
History Of

AbstractHow did galaxies evolve from primordial fluctuations to the well-ordered but diverse population of disk and elliptical galaxies that we observe today? Stellar populations synthesis models have become a crucial tool in addressing this question by helping us to interpret the spectral energy distributions of present-day galaxies and their high redshift progenitors in terms of fundamental characteristics such as stellar mass and age. I will review our current knowledge on the evolution of stellar populations in early- and late type galaxies at z < 1 and the tantalizing – but incomplete – view of the stellar populations in galaxies at 1 < z < 3, during the global peak of star formation. Despite great progress, many fundamental questions remain: what processes trigger episodes of galaxy-scale star formation and what quenches them? To what degree does the star formation history of galaxies depend on the merger history, (halo) mass, or local environment? I will discuss some of the challenges posed in interpreting current data and what improved results might be expected from new observational facilities in the near- and more distant future.

The occurrence of species flocks in the nematode genus Cloacina (Strongyloidea : Cloacininae), parasitic in the stomachs of kangaroos and wallabies

2002 ◽  
Vol 50 (6) ◽  
pp. 597 ◽  
Author(s):  
I. Beveridge ◽  
N. B. Chilton ◽  
D. M. Spratt
Keyword(s):  
Host Specificity ◽  
Host Species ◽  
Nematode Species ◽  
Morphological Data ◽  
Species Flock ◽  
Sampling Effort ◽  
Nematode Genus ◽  
Single Host ◽  
Species Flocks ◽  
Occurrence Of Species

The occurrence of species flocks within the nematode genus Cloacina was examined using the criteria of host specificity, co-occurrence and monophyly. Species of Cloacina generally exhibited a high degree of host specificity, with most species occurring either in a single host species or in two closely related host species. The frequency distribution of numbers of component species of Cloacina per host species indicated that most host species harboured 2–4 species of nematodes, with an approximately exponential decline in the number of species of parasites to a maximum of 20 species of nematode per host species. Host species harbouring eight or more species of Cloacina were found within a single recent macropodid clade, but there was no correlation between evolutionary age of the host and the number of parasite species harboured. Sampling effort was significantly correlated with the number of nematode species found and, in partial regression analysis, subsumed the effects of host body size and geographic range, which were found to be significant correlates with the number of nematode species present in preliminary analyses. Analysis of co-occurrences of nematode species indicated significant variation between host species, with some hosts (e.g. Macropus agilis) most commonly harbouring a single species of Cloacina, while closely related host species (e.g. M. dorsalis) most commonly harboured numerous species. Parsimony analysis of species of Cloacina based on morphological data suggested that while small series of related nematode species could be identified within a single host species, the species flock in each host species is polyphyletic in origin. Species flocks contributed significantly to community richness in some host species.

scholarly journals Molecular Properties and New Potentials of Plant Nepenthesins

Plants ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 570
Author(s):  
Zelalem Eshetu Bekalu ◽  
Giuseppe Dionisio ◽  
Henrik Brinch-Pedersen
Keyword(s):  
Current Knowledge ◽  
Industrial Applications ◽  
Biochemical Properties ◽  
Carnivorous Plant ◽  
Current Data ◽  
Fungal Resistance ◽  
Limited Attention ◽  
Specific Sequence ◽  
Aspartic Proteases ◽  
Trait Improvement

Nepenthesins are aspartic proteases (APs) categorized under the A1B subfamily. Due to nepenthesin-specific sequence features, the A1B subfamily is also named nepenthesin-type aspartic proteases (NEPs). Nepenthesins are mostly known from the pitcher fluid of the carnivorous plant Nepenthes, where they are availed for the hydrolyzation of insect protein required for the assimilation of insect nitrogen resources. However, nepenthesins are widely distributed within the plant kingdom and play significant roles in plant species other than Nepenthes. Although they have received limited attention when compared to other members of the subfamily, current data indicates that they have exceptional molecular and biochemical properties and new potentials as fungal-resistance genes. In the current review, we provide insights into the current knowledge on the molecular and biochemical properties of plant nepenthesins and highlights that future focus on them may have strong potentials for industrial applications and crop trait improvement.

scholarly journals Rhombencephalitis Caused byListeria monocytogenesin Humans and Ruminants: A Zoonosis on the Rise?

2010 ◽  
Vol 2010 ◽  
pp. 1-22 ◽  
Author(s):  
Anna Oevermann ◽  
Andreas Zurbriggen ◽  
Marc Vandevelde
Keyword(s):  
Listeria Monocytogenes ◽  
High Mortality ◽  
Host Species ◽  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Therapeutic Strategies ◽  
Zoonotic Infection ◽  
Cns Disease ◽  
The Brain

Listeriosis is an emerging zoonotic infection of humans and ruminants worldwide caused byListeria monocytogenes(LM). In both host species, CNS disease accounts for the high mortality associated with listeriosis and includes rhombencephalitis, whose neuropathology is strikingly similar in humans and ruminants. This review discusses the current knowledge about listeric encephalitis, and involved host and bacterial factors. There is an urgent need to study the molecular mechanisms of neuropathogenesis, which are poorly understood. Such studies will provide a basis for the development of new therapeutic strategies that aim to prevent LM from invading the brain and spread within the CNS.

scholarly journals Raw Sewage Harbors Diverse Viral Populations

mBio ◽  
2011 ◽  
Vol 2 (5) ◽  
Author(s):  
Paul G. Cantalupo ◽  
Byron Calgua ◽  
Guoyan Zhao ◽  
Ayalkibet Hundesa ◽  
Adam D. Wier ◽  
...  
Keyword(s):  
Genetic Material ◽  
Viral Diversity ◽  
Emerging Pathogens ◽  
Viral Genomes ◽  
Untreated Wastewater ◽  
Virus Diversity ◽  
Double Stranded Dna ◽  
Large Numbers ◽  
Ideal System ◽  
Species Specific

ABSTRACTAt this time, about 3,000 different viruses are recognized, but metagenomic studies suggest that these viruses are a small fraction of the viruses that exist in nature. We have explored viral diversity by deep sequencing nucleic acids obtained from virion populations enriched from raw sewage. We identified 234 known viruses, including 17 that infect humans. Plant, insect, and algal viruses as well as bacteriophages were also present. These viruses represented 26 taxonomic families and included viruses with single-stranded DNA (ssDNA), double-stranded DNA (dsDNA), positive-sense ssRNA [ssRNA(+)], and dsRNA genomes. Novel viruses that could be placed in specific taxa represented 51 different families, making untreated wastewater the most diverse viral metagenome (genetic material recovered directly from environmental samples) examined thus far. However, the vast majority of sequence reads bore little or no sequence relation to known viruses and thus could not be placed into specific taxa. These results show that the vast majority of the viruses on Earth have not yet been characterized. Untreated wastewater provides a rich matrix for identifying novel viruses and for studying virus diversity.IMPORTANCEAt this time, virology is focused on the study of a relatively small number of viral species. Specific viruses are studied either because they are easily propagated in the laboratory or because they are associated with disease. The lack of knowledge of the size and characteristics of the viral universe and the diversity of viral genomes is a roadblock to understanding important issues, such as the origin of emerging pathogens and the extent of gene exchange among viruses. Untreated wastewater is an ideal system for assessing viral diversity because virion populations from large numbers of individuals are deposited and because raw sewage itself provides a rich environment for the growth of diverse host species and thus their viruses. These studies suggest that the viral universe is far more vast and diverse than previously suspected.

Sign in / Sign up

Export Citation Format

Share Document