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1.
Mol Phylogenet Evol ; 188: 107890, 2023 11.
Article in English | MEDLINE | ID: mdl-37517508

ABSTRACT

African-Malagasy species of the bat genus Miniopterus are notable both for the dramatic increase in the number of newly recognized species over the last 15 years, as well as for the profusion of new taxa from Madagascar and the neighboring Comoros. Since 2007, seven new Malagasy Miniopterus species have been described compared to only two new species since 1936 from the Afrotropics. The conservative morphology of Miniopterus and limited geographic sampling in continental Africa have undoubtedly contributed to the deficit of continental species. In addition to uncertainty over species limits, phylogenetic relationships of Miniopterus remain mostly unresolved, particularly at deeper backbone nodes. Previous phylogenetic studies were based on limited taxon sampling and/or limited genetic sampling involving no more than five loci. Here, we conduct the first phylogenomic study of the Afrotropical Miniopteridae by analyzing up to 3772 genome-wide ultraconserved elements (UCEs) from historic and modern samples of 70 individuals from 25 Miniopterus species/lineages. We analyze multiple datasets of varying degrees of completeness (70, 90, and 100 percent complete) using partitioned concatenated maximum likelihood and multispecies coalescent methods. Our well-supported, species-level phylogenies resolved most (6/8 or 7/8) backbone nodes and strongly support for the first time the monophyly of the Malagasy radiation. We inferred the crown age of African Miniopteridae in the late Miocene (10.4 Ma), while the main lineages of Miniopterus appear to have contemporaneously diversified in two sister radiations in the Afrotropics and Madagascar. Species-level divergence of 23 of 25 African + Malagasy Miniopterus were estimated to have 95 % HPDs that overlap with the late Miocene (5.3-10.4 Ma). We present ancestral range estimates that unambiguously support a continental African radiation that originated in the Zambezian and Somalian/Ethiopian biogeographic regions, but we cannot rule out back colonization of Africa from Madagascar. The phylogeny indicates genetic support for up to seven new species.


Subject(s)
Chiroptera , Humans , Animals , Phylogeny , Chiroptera/genetics , Africa , Madagascar
2.
Conserv Biol ; : e14221, 2023 Nov 08.
Article in English | MEDLINE | ID: mdl-37937455

ABSTRACT

Reliable maps of species distributions are fundamental for biodiversity research and conservation. The International Union for Conservation of Nature (IUCN) range maps are widely recognized as authoritative representations of species' geographic limits, yet they might not always align with actual occurrence data. In recent area of habitat (AOH) maps, areas that are not habitat have been removed from IUCN ranges to reduce commission errors, but their concordance with actual species occurrence also remains untested. We tested concordance between occurrences recorded in camera trap surveys and predicted occurrences from the IUCN and AOH maps for 510 medium- to large-bodied mammalian species in 80 camera trap sampling areas. Across all areas, cameras detected only 39% of species expected to occur based on IUCN ranges and AOH maps; 85% of the IUCN only mismatches occurred within 200 km of range edges. Only 4% of species occurrences were detected by cameras outside IUCN ranges. The probability of mismatches between cameras and the IUCN range was significantly higher for smaller-bodied mammals and habitat specialists in the Neotropics and Indomalaya and in areas with shorter canopy forests. Our findings suggest that range and AOH maps rarely underrepresent areas where species occur, but they may more often overrepresent ranges by including areas where a species may be absent, particularly at range edges. We suggest that combining range maps with data from ground-based biodiversity sensors, such as camera traps, provides a richer knowledge base for conservation mapping and planning.


Combinación de censos con fototrampas y mapas de extensión de la UICN para incrementar el conocimiento sobre la distribución de las especies Resumen Los mapas confiables de la distribución de las especies son fundamentales para la investigación y conservación de la biodiversidad. Los mapas de distribución de la Unión Internacional para la Conservación de la Naturaleza (UICN) están reconocidos como representaciones de autoridad de los límites geográficos de las especies, aunque no siempre se alinean con los datos actuales de su presencia. En los mapas recientes de área de hábitat (ADH), las áreas que no son hábitat han sido eliminadas de la distribución de la UICN para reducir los errores de comisión, pero su concordancia con la presencia actual de las especies tampoco ha sido analizada. Analizamos la concordancia entre la presencia registrada por los censos de fototrampas y pronosticamos la presencia a partir de los mapas de la UICN y de ADH de 510 especies de mamíferos de talla mediana a grande en 80 áreas de muestreo de fototrampas. Las cámaras detectaron sólo el 39% de las especies esperadas con base en la distribución de la UICN y los mapas de ADH en todas las áreas; el 85% de las disparidades con la UICN ocurrieron dentro de los 200 km a partir del borde de la distribución. Sólo el 4% de la presencia de las especies fue detectada por las cámaras ubicadas fuera de la distribución de la UICN. La probabilidad de disparidad entre las cámaras y la UICN fue significativamente mayor para los mamíferos de talla pequeña y para los especialistas de hábitat en las regiones Neotropical e Indomalaya y en áreas con doseles forestales más bajos. Nuestros hallazgos sugieren que los mapas de distribución y ADH pocas veces subrepresentan las áreas con presencia de las especies, pero con frecuencia pueden sobrerrepresentar la distribución al incluir áreas en donde las especies pueden estar ausentes, en particular los bordes de la distribución. Sugerimos que la combinación de los mapas de distribución con los sensores de biodiversidad en tierra, como las fototrampas, proporciona una base más rica de conocimiento para el mapeo y la planeación de la conservación.

3.
Arch Virol ; 166(12): 3513-3566, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34463877

ABSTRACT

In March 2021, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by four families (Aliusviridae, Crepuscuviridae, Myriaviridae, and Natareviridae), three subfamilies (Alpharhabdovirinae, Betarhabdovirinae, and Gammarhabdovirinae), 42 genera, and 200 species. Thirty-nine species were renamed and/or moved and seven species were abolished. This article presents the updated taxonomy of Negarnaviricota as now accepted by the ICTV.


Subject(s)
Mononegavirales , Viruses , Humans
4.
Rev Med Virol ; 29(6): e2079, 2019 11.
Article in English | MEDLINE | ID: mdl-31410931

ABSTRACT

In the last decade, virus hunting and discovery has gained pace. This achievement has been driven by three major factors: (a) advancements in sequencing technologies, (b) scaled-up routine arbovirus surveillance strategies, and (c) the "hunt" for emerging pathogens and novel viruses. Many novel viruses have been discovered from a myriad of hosts, vectors, and environmental samples. To help promote understanding of the global diversity and distribution of mosquito-associated viruses and facilitate future studies, we review mosquito-associated viruses discovered between years 2007 and 2017, across the world. In the analyzed period, novel mosquito-associated viruses belonging to 25 families and a general group of unclassified viruses were categorized. The top three discovered novel mosquito-associated viruses belonged to families Flaviviridae (n=32), Rhabdoviridae (n=16), and Peribunyaviridae (n=14). Also, 67 unclassified viruses were reported. Majority of these novel viruses were identified from Culex spp, Anopheles spp, Aedes spp, and Mansonia spp mosquitoes, respectively. Notably, the number of these discovered novels is not representative of intercontinental virus diversity but rather is influenced by the number of studies done in the study period. Some of these newly discovered mosquito-associated viruses have medical significance, either directly or indirectly. For instance, in the study period, 14 novel mosquito-borne viruses that infect mammalian cells in vitro were reported. These viruses pose a danger to the global health security on emerging viral diseases. On the other hand, some of the newly discovered insect specific viruses described herein have potential application as future biocontrol and vaccine agents against known pathogenic arboviruses. Overall, this review outlines the crucial role played by mosquitoes as viral vectors in the global virosphere.


Subject(s)
Aedes/virology , Mosquito Vectors/virology , Viruses/classification , Viruses/genetics , Animals , Genes, Viral , Phylogeny , Phylogeography , Viruses/isolation & purification
5.
Ecology ; 98(7): 1839-1848, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28403506

ABSTRACT

Biodiversity loss can alter disease transmission; however, the magnitude and direction of these effects vary widely across ecosystems, scales, and pathogens. Here we experimentally examine the effects of one of the most globally pervasive patterns of biodiversity decline, the selective loss of large wildlife, on infection probability, intensity and population size of a group of common rodent-borne parasites - macroparasitic helminths. Consistent with previous work on vector-borne pathogens, we found that large wildlife removal causes strong and systematic increases of rodent-borne parasites, largely due to increases in rodent density, as rodents are released from competition with larger herbivores. Although we predicted that increased host density would also increase per capita infection among all directly transmitted parasites, this additional amplification occurred for only two of three examined parasites. Furthermore, the actual effects of large mammal loss on per capita infection were mediated by the complex suite of abiotic and biotic factors that regulate parasite transmission. Thus, while these results strongly suggest that large wildlife loss will cause systematic increases in rodent parasite populations, they also underscore the difficulty of making more specific predictions for a given parasite based on simple attributes such as transmission mode or life history strategy. Instead, detailed information on the ecology of each parasite species would be necessary to make more accurate predictions of how biodiversity loss will affect infection.


Subject(s)
Ecosystem , Grassland , Parasites , Africa , Animals , Animals, Wild , Biodiversity , Host-Parasite Interactions
7.
Proc Natl Acad Sci U S A ; 110(20): 8194-9, 2013 May 14.
Article in English | MEDLINE | ID: mdl-23610427

ABSTRACT

Although there are over 1,150 bat species worldwide, the diversity of viruses harbored by bats has only recently come into focus as a result of expanded wildlife surveillance. Such surveys are of importance in determining the potential for novel viruses to emerge in humans, and for optimal management of bats and their habitats. To enhance our knowledge of the viral diversity present in bats, we initially surveyed 415 sera from African and Central American bats. Unbiased high-throughput sequencing revealed the presence of a highly diverse group of bat-derived viruses related to hepaciviruses and pegiviruses within the family Flaviridae. Subsequent PCR screening of 1,258 bat specimens collected worldwide indicated the presence of these viruses also in North America and Asia. A total of 83 bat-derived viruses were identified, representing an infection rate of nearly 5%. Evolutionary analyses revealed that all known hepaciviruses and pegiviruses, including those previously documented in humans and other primates, fall within the phylogenetic diversity of the bat-derived viruses described here. The prevalence, unprecedented viral biodiversity, phylogenetic divergence, and worldwide distribution of the bat-derived viruses suggest that bats are a major and ancient natural reservoir for both hepaciviruses and pegiviruses and provide insights into the evolutionary history of hepatitis C virus and the human GB viruses.


Subject(s)
Chiroptera/virology , Disease Reservoirs/veterinary , Flaviviridae/genetics , Hepacivirus/genetics , Virus Diseases/virology , Amino Acid Sequence , Animals , Bayes Theorem , Codon , Disease Reservoirs/virology , Genetic Variation , Genome, Viral , Geography , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Virus Diseases/veterinary
8.
Emerg Infect Dis ; 21(10): 1840-3, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26402433

ABSTRACT

As part of a larger survey for detection of pathogens among wildlife in sub-Saharan Africa conducted during 2007-2012, multiple diverse paramyxovirus sequences were detected in renal tissues of bats. Phylogenetic analysis supports the presence of at least 2 major viral lineages and suggests that paramyxoviruses are strongly associated with several bat genera.


Subject(s)
Chiroptera/virology , Henipavirus/pathogenicity , Paramyxoviridae Infections/epidemiology , Paramyxovirinae/classification , Prevalence , Africa South of the Sahara/epidemiology , Animals , Paramyxoviridae Infections/virology , Phylogeny , Population Surveillance/methods , RNA, Viral/classification , RNA, Viral/genetics
9.
Ecol Appl ; 25(2): 348-60, 2015 Mar.
Article in English | MEDLINE | ID: mdl-26263659

ABSTRACT

Many species of large wildlife have declined drastically worldwide. These reductions often lead to profound shifts in the ecology of entire communities and ecosystems. However, the effects of these large-wildlife declines on other taxa likely hinge upon both underlying abiotic properties of these systems and on the types of secondary anthropogenic changes associated with wildlife loss, making impacts difficult to predict. To better understand how these important contextual factors determine the consequences of large-wildlife declines on other animals in a community, we examined the effects of three common forms of large-wildlife loss (removal without replacement [using fences], removal followed by replacement with domestic stock, and removal accompanied by crop agricultural use) on small-mammal abundance, diversity, and community composition, in landscapes that varied in several abiotic attributes (rainfall, soil fertility, land-use intensity) in central Kenya. We found that small-mammal communities were indeed heavily impacted by all forms of large-wildlife decline, showing, on average: (1) higher densities, (2) lower species richness per site, and (3) different species assemblages in sites from which large wildlife were removed. However, the nature and magnitude of these effects were strongly context dependent. Rainfall, type of land-use change, and the interaction of these two factors were key predictors of both the magnitude and type of responses of small mammals. The strongest effects, particularly abundance responses, tended to be observed in low-rainfall areas. Whereas isolated wildlife removal primarily led to increased small-mammal abundance, wildlife removal associated with secondary uses (agriculture, domestic stock) had much more variable effects on abundance and stronger impacts on diversity and composition. Collectively, these results (1) highlight the importance of context in determining the impacts of large-wildlife decline on small-mammal communities, (2) emphasize the challenges in extrapolating results from controlled experimental studies to predict the effects of wildlife declines that are accompanied by secondary land-uses, and (3) suggest that, because of the context-dependent nature of the responses to large-wildlife decline, large-wildlife status alone cannot be reliably used to predict small-mammal community changes.


Subject(s)
Animals, Wild , Biodiversity , Body Size , Animals , Conservation of Natural Resources , Kenya , Population Dynamics
10.
Mol Phylogenet Evol ; 71: 41-54, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24184338

ABSTRACT

The Eastern Afromontane region of Africa is characterized by striking levels of endemism and species richness accompanied by significant conservation threat, a pattern typical across biodiversity hotspots. Using multi-locus molecular data under a coalescent species tree framework we identify major cryptic biogeographic patterns within and between two endemic montane small mammal species complexes, Hylomyscus mice and Sylvisorex shrews, co-distributed across the Albertine Rift and Kenya Highlands of the Eastern Afromontane Biodiversity Hotspot (EABH). Hypotheses put forward to account for the high diversity of the region include retention of older palaeo-endemic lineages across major regions in climatically stable refugia, as well as the accumulation of lineages associated with more recent differentiation between allopatric populations separated by unsuitable habitat during periods of Pleistocene aridification. Sympatric pairs of sister lineages were found to have significantly older divergence times than allopatric pairs. Genetic analyses and historical distribution modeling suggest that regional meta-populations have persisted since the Pliocene to mid-Pleistocene across a climatic gradient from the Albertine Rift in the west to the Kenya Highlands in the east for both focal taxa. Differing patterns of regional sub-division and demographic expansion were detected and are consistent with differing life histories as well as shared responses to regional variation in stability of suitable habitat. There is also strong support in both mice and shrew species for Late Miocene divergence with subsequent range expansion into sympatry in previously unidentified cryptic species pairs. These results highlight the broad temporal scale at which climatic and geological changes may have facilitated rare dispersal events between montane habitats as well as the long-term persistence of populations in both the Albertine Rift and the Kenyan Highlands that together contributed to the high species diversity and endemism in the EABH.


Subject(s)
Biodiversity , Murinae/genetics , Phylogeny , Shrews/genetics , Africa, Eastern , Animals , Sequence Analysis, DNA
11.
Ecol Evol ; 14(4): e11151, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38601855

ABSTRACT

Conservation areas encompassing elevation gradients are biodiversity hotspots because they contain a wide range of habitat types in a relatively small space. Studies of biodiversity patterns along elevation gradients, mostly on small mammal or bird species, have documented a peak in diversity at mid elevations. Here, we report on a field study of medium and large mammals to examine the impact of elevation, habitat type, and gross primary productivity on community structure. Species richness was observed using a camera trap transect with 219 sites situated across different habitat types from 2329 to 4657 m above the sea level on the western slope of Mt Kenya, the second highest mountain in Africa. We found that the lowest elevation natural habitats had the highest species richness and relative abundance and that both metrics decreased steadily as elevation increased, paralleling changes in gross primary productivity, and supporting the energy richness hypothesis. We found no evidence for the mid-domain effect on species diversity. The lowest elevation degraded Agro-Forestry lands adjacent to the National Park had high activity of domestic animals and reduced diversity and abundance of native species. The biggest difference in community structure was between protected and unprotected areas, followed by more subtle stepwise differences between habitats at different elevations. Large carnivore species remained relatively consistent but dominant herbivore species shifted along the elevation gradient. There was some habitat specialization and turnover in species, such that the elevation gradient predicts a high diversity of species, demonstrating the high conservation return for protecting mountain ecosystems for biodiversity conservation.

12.
Virus Res ; 339: 199266, 2024 01 02.
Article in English | MEDLINE | ID: mdl-37944758

ABSTRACT

Surveillance of mosquito vectors is critical for early detection, prevention and control of vector borne diseases. In this study we used advanced molecular tools, such as DNA barcoding in combination with novel sequencing technologies to discover new and already known viruses in genetically identified mosquito species. Mosquitoes were captured using BG sentinel traps in Western Kenya during May and July 2019, and homogenized individually before pooled into groups of ten mosquitoes. The pools and individual samples were then used for molecular analysis and to infect cell cultures. Of a total of fifty-four (54) 10-pools, thirteen (13) showed cytopathic effect (CPE) on VeroB4 cells, eighteen (18) showed CPE on C6/36 cells. Eight (8) 10-pools out of the 31 CPE positive pools showed CPE on both VeroB4 and C6/36 cells. When using reverse transcriptase polymerase chain reaction (RT-PCR), Sanger sequencing and Twist Comprehensive Viral Research Panel (CVRP) (Twist Biosciences), all pools were found negative by RT-PCR when using genus specific primers targeting alphaviruses, orthobunyaviruses and virus specific primers towards o'nyong-nyong virus, chikungunya virus and Sindbis virus (previously reported to circulate in the region). Interestingly, five pools were RT-PCR positive for flavivirus. Two of the RT-PCR positive pools showed CPE on both VeroB4 and C6/36 cells, two pools showed CPE on C6/36 cells alone and one pool on VeroB4 cells only. Fifty individual mosquito homogenates from the five RT-PCR positive 10-pools were analyzed further for flavivirus RNA. Of these, 19 out of the 50 individual mosquito homogenates indicated the presence of flavivirus RNA. Barcoding of the flavivirus positive mosquitoes revealed the mosquito species as Aedes aegypti (1), Mansonia uniformis (6), Anopheles spp (3), Culex pipiens (5), Culex spp (1), Coquilletidia metallica (2) and Culex quinquefasciatus (1). Of the 19 flavivirus positive individual mosquitoes, five (5) virus positive homogenates were sequenced. Genome sequences of two viruses were completed. One was identified as the single-stranded RNA Culex flavivirus and the other as the double-stranded RNA Hubei chryso-like virus 1. Both viruses were found in the same Anopheles spp. homogenate extracted from a sample that showed CPE on both VeroB4 and C6/36 cells. The detection of both viruses in a single mosquito homogenate indicated coinfection. Phylogenetic analyses suggested that the Culex flavivirus sequence detected was closely related to a Culex flavivirus isolated from Uganda in 2008. All four Hubei chryso-like virus 1 segments clusters closely to Hubei chryso-like virus 1 strains isolated in Australia, China and USA. Two novel strains of insect-specific viruses in Anopheles mosquitoes were detected and characterized.


Subject(s)
Anopheles , Culex , Flavivirus , Insect Viruses , Animals , Anopheles/genetics , Phylogeny , Kenya , Insect Viruses/genetics , RNA
13.
Infect Dis (Lond) ; : 1-7, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38913503

ABSTRACT

BACKGROUND: Although the diverse communities of tick-borne viruses (TBVs) have recently been proposed, the threat of infection and exposure to TBVs among humans across Kenya has been poorly understood. OBJECTIVE: Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne viral agent associated with the epidemic of severe fever with thrombocytopenia syndrome (SFTS) disease in East Asian countries. This study investigated the seroprevalence of SFTSV among humans in Kenya. METHODS: Serum samples were collected from 459 healthy people in Kenya and tested for anti-SFTSV antibodies, which were further confirmed by immunofluorescence assays. Micro neutralization assays were performed to identify neutralising antibodies against SFTSV and SFTSV-related viruses. RESULTS: A high seroprevalence (162/459, 35.3%) of SFTSV was found in the samples from nine of the ten surveyed counties in Kenya, with higher rates in the eastern plateau forelands, semiarid and arid areas, and coastal areas than in the area aside Rift valley. The seropositive rate was slightly higher in women than in men and was significantly higher in the 55-64 age group. Neutralising activity against SFTSV was detected in four samples, resulting in a rate of 0.9%. No cross-neutralising activity against the SFTSV-related Guertu virus and Heartland virus was detected in the anti-SFTSV positive serum samples. CONCLUSION: The results provide serologic evidence of human exposure to SFTSV in Kenya and extend our understanding of SFTSV prevalence from Asia to Africa. The findings suggest an increasing threat of exposure to emerging TBVs and the need to investigate tick viromes in Kenya.

14.
Microbiome ; 12(1): 72, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38600530

ABSTRACT

BACKGROUND: Zoonotic viruses cause substantial public health and socioeconomic problems worldwide. Understanding how viruses evolve and spread within and among wildlife species is a critical step when aiming for proactive identification of viral threats to prevent future pandemics. Despite the many proposed factors influencing viral diversity, the genomic diversity and structure of viral communities in East Africa are largely unknown. RESULTS: Using 38.3 Tb of metatranscriptomic data obtained via ultradeep sequencing, we screened vertebrate-associated viromes from 844 bats and 250 rodents from Kenya and Uganda collected from the wild. The 251 vertebrate-associated viral genomes of bats (212) and rodents (39) revealed the vast diversity, host-related variability, and high geographic specificity of viruses in East Africa. Among the surveyed viral families, Coronaviridae and Circoviridae showed low host specificity, high conservation of replication-associated proteins, high divergence among viral entry proteins, and frequent recombination. Despite major dispersal limitations, recurrent mutations, cocirculation, and occasional gene flow contribute to the high local diversity of viral genomes. CONCLUSIONS: The present study not only shows the landscape of bat and rodent viromes in this zoonotic hotspot but also reveals genomic signatures driven by the evolution and dispersal of the viral community, laying solid groundwork for future proactive surveillance of emerging zoonotic pathogens in wildlife. Video Abstract.


Subject(s)
Chiroptera , Viruses , Animals , Animals, Wild , Genome, Viral/genetics , Phylogeny , Recombination, Genetic , Rodentia , Uganda/epidemiology
15.
J Gen Virol ; 94(Pt 11): 2393-2398, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23939976

ABSTRACT

Zoonotic and vector-borne pathogens have comprised a significant component of emerging human infections in recent decades, and bats are increasingly recognized as reservoirs for many of these disease agents. To identify novel pathogens associated with bats, we screened tissues of bats collected in Kenya. Virus isolates were identified by next generation sequencing of viral nucleic acid preparations from the infected cell culture supernatant and characterized. Here we report the identification of Fikirini rhabdovirus, a novel rhabdovirus isolated from a bat, Hipposideros vittatus, captured along the Kenyan coast.


Subject(s)
Chiroptera/virology , Rhabdoviridae Infections/veterinary , Rhabdoviridae/genetics , Animals , Disease Reservoirs/virology , High-Throughput Nucleotide Sequencing/methods , Kenya , Liver/virology , Molecular Sequence Data , Phylogeny , RNA, Viral/genetics , Rhabdoviridae/classification , Rhabdoviridae/isolation & purification , Rhabdoviridae Infections/virology , Sequence Analysis, DNA/methods
16.
J Gen Virol ; 94(Pt 4): 738-748, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23239573

ABSTRACT

Polyomaviruses (PyVs) have been identified in a wide range of avian and mammalian species. However, little is known about their occurrence, genetic diversity and evolutionary history in bats, even though bats are important reservoirs for many emerging viral pathogens. This study screened 380 specimens from 35 bat species from Kenya and Guatemala for the presence of PyVs by semi-nested pan-PyV PCR assays. PyV DNA was detected in 24 of the 380 bat specimens. Phylogenetic analysis revealed that the bat PyV sequences formed 12 distinct lineages. Full-genome sequences were obtained for seven representative lineages and possessed similar genomic features to known PyVs. Strikingly, this evolutionary analysis revealed that the bat PyVs were paraphyletic, suggestive of multiple species jumps between bats and other mammalian species, such that the theory of virus-host co-divergence for mammalian PyVs as a whole could be rejected. In addition, evidence was found for strong heterogeneity in evolutionary rate and potential recombination in a number of PyV complete genomes, which complicates both phylogenetic analysis and virus classification. In summary, this study revealed that bats are important reservoirs of PyVs and that these viruses have a complex evolutionary history.


Subject(s)
Chiroptera/virology , DNA, Viral/genetics , Evolution, Molecular , Genetic Variation , Genome, Viral , Polyomavirus/genetics , Polyomavirus/isolation & purification , Animals , Cluster Analysis , DNA, Viral/chemistry , Guatemala , Kenya , Molecular Sequence Data , Phylogeny , Polyomavirus/classification , Sequence Analysis, DNA
17.
Am J Primatol ; 75(4): 350-60, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23307319

ABSTRACT

African green monkeys (Chlorocebus) represent a widely distributed and morphologically diverse primate genus in sub-Saharan Africa. Little attention has been paid to their genetic diversity and phylogeny. Based on morphological data, six species are currently recognized, but their taxonomy remains disputed. Here, we aim to characterize the mitochondrial (mt) DNA diversity, biogeography and phylogeny of African green monkeys. We analyzed the complete mitochondrial cytochrome b gene of 126 samples using feces from wild individuals and material from zoo and museum specimens with clear geographical provenance, including several type specimens. We found evidence for nine major mtDNA clades that reflect geographic distributions rather than taxa, implying that the mtDNA diversity of African green monkeys does not conform to existing taxonomic classifications. Phylogenetic relationships among clades could not be resolved suggesting a rapid early divergence of lineages. Several discordances between mtDNA and phenotype indicate that hybridization may have occurred in contact zones among species, including the threatened Bale monkey (Chlorocebus djamdjamensis). Our results provide both valuable data on African green monkeys' genetic diversity and evolution and a basis for further molecular studies on this genus.


Subject(s)
Chlorocebus aethiops/classification , Chlorocebus aethiops/genetics , DNA, Mitochondrial/genetics , Genetic Variation/genetics , Africa South of the Sahara , Animals , Cytochromes b/genetics , DNA/analysis , Demography , Hybridization, Genetic/genetics , Phylogeny , Polymerase Chain Reaction/veterinary , Sequence Analysis, DNA
18.
Proc Biol Sci ; 279(1729): 675-80, 2012 Feb 22.
Article in English | MEDLINE | ID: mdl-21813554

ABSTRACT

Plant toxins are sequestered by many animals and the toxicity is frequently advertised by aposematic displays to deter potential predators. Such 'unpalatability by appropriation' is common in many invertebrate groups and also found in a few vertebrate groups. However, potentially lethal toxicity by acquisition has so far never been reported for a placental mammal. Here, we describe complex morphological structures and behaviours whereby the African crested rat, Lophiomys imhausi, acquires, dispenses and advertises deterrent toxin. Roots and bark of Acokanthera schimperi (Apocynaceae) trees are gnawed, masticated and slavered onto highly specialized hairs that wick up the compound, to be delivered whenever the animal is bitten or mouthed by a predator. The poison is a cardenolide, closely resembling ouabain, one of the active components in a traditional African arrow poison long celebrated for its power to kill elephants.


Subject(s)
Apocynaceae/chemistry , Hair , Muridae/physiology , Toxins, Biological , Adaptation, Physiological , Animals , Behavior, Animal , Hair/anatomy & histology , Hair/ultrastructure , Muridae/anatomy & histology , Ouabain/chemistry , Spectroscopy, Fourier Transform Infrared
19.
Virol Sin ; 37(4): 491-502, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35680114

ABSTRACT

Emergence and re-emergence of infectious diseases of wildlife origin have led pre-emptive pathogen surveillances in animals to be a public health priority. Rodents and shrews are among the most numerically abundant vertebrate taxa and are known as natural hosts of important zoonotic viruses. Many surveillance programs focused more on RNA viruses. In comparison, much less is known about DNA viruses harbored by these small mammals. To fill this knowledge gap, tissue specimens of 232 animals including 226 rodents, five shrews and one hedgehog were collected from 5 counties in Kenya and tested for the presence of DNA viruses belonging to 7 viral families by PCR. Diverse DNA sequences of adenoviruses, adeno-associated viruses, herpesviruses and polyomaviruses were detected. Phylogenetic analyses revealed that most of these viruses showed distinction from previously described viruses and formed new clusters. Furthermore, this is the first report of the discovery and full-length genome characterization of a polyomavirus in Lemniscomys species. This novel polyomavirus, named LsPyV KY187, has less than 60% amino acid sequence identity to the most related Glis glis polyomavirus 1 and Sciurus carolinensis polyomavirus 1 in both large and small T-antigen proteins and thus can be putatively allocated to a novel species within Betapolyomavirus. Our findings help us better understand the genetic diversity of DNA viruses in rodent and shrew populations in Kenya and provide new insights into the evolution of those DNA viruses in their small mammal reservoirs. It demonstrates the necessity of ongoing pathogen discovery studies targeting rodent-borne viruses in East Africa.


Subject(s)
Herpesviridae , Polyomavirus , Animals , Genome, Viral , Kenya , Murinae , Phylogeny , Polyomavirus/genetics , Shrews/genetics
20.
Zootaxa ; 4948(2): zootaxa.4948.2.5, 2021 Mar 19.
Article in English | MEDLINE | ID: mdl-33757027

ABSTRACT

A new subspecies of giant sengi or elephant-shrew, first documented in 2008, is described from northern coastal Kenya. All five currently described species and most known subspecies of Rhynchocyon are compared to this new lineage. Molecular analyses using mitochondrial and nuclear markers from the single DNA sample available for the new lineage show differences from other forms and reveal a close relationship with the allopatric golden-rumped sengi R. chrysopygus (0.43% divergence at the 12S mitochondrial locus). This level of 12S divergence is similar to that between other subspecies pairs within Rhynchocyon. Based on three voucher specimens and 843 images from camera traps, the new lineage is similar to R. chrysopygus in the rufous-maroon sides and shoulders but is distinguished by the lack of the golden rump, the presence of jet-black distal rump and thighs, dark dorsal line, and a pronounced nuchal crest of hairs. Though it also shows superficial pelage similarities to two Tanzania species, R. udzungwensis and the dark coastal form of R. cirnei macrurus, the new form has differences in pelage coloration that are clearly diagnosable from all other taxa. This new lineage has an allopatric distribution to all known Rhynchocyon taxa, with the closest congener being R. chrysopygus located 140 km apart. We estimate a potential range size for the new taxon of ~1980 km2 in the Boni and Dodori National Reserves with habitat consisting of mixed thickets and dry forests. Because of its close genetic relationship with R. chrysopygus, its allopatric distribution, and divergent coloration, the new subspecies is designated Rhynchocyon chrysopygus mandelai. The previously described populations of R. chrysopygus from southern coastal Kenya are now designated R. chrysopygus chrysopygus. As the current severe political insecurity in the area threatens the new taxon, we hope that its description will help establish immediate conservation priorities and action for the subspecies and its habitat.


Subject(s)
Ecosystem , Shrews , Animals , Kenya , Phylogeny
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