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1.
Nat Commun ; 15(1): 2887, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575573

RESUMO

Anthropogenic disturbances and the subsequent loss of biodiversity are altering species abundances and communities. Since species vary in their pathogen competence, spatio-temporal changes in host assemblages may lead to changes in disease dynamics. We explore how longitudinal changes in bat species assemblages affect the disease dynamics of coronaviruses (CoVs) in more than 2300 cave-dwelling bats captured over two years from five caves in Ghana. This reveals uneven CoV infection patterns between closely related species, with the alpha-CoV 229E-like and SARS-related beta-CoV 2b emerging as multi-host pathogens. Prevalence and infection likelihood for both phylogenetically distinct CoVs is influenced by the abundance of competent species and naïve subadults. Broadly, bat species vary in CoV competence, and highly competent species are more common in less diverse communities, leading to increased CoV prevalence in less diverse bat assemblages. In line with the One Health framework, our work supports the notion that biodiversity conservation may be the most proactive measure to prevent the spread of pathogens with zoonotic potential.


Assuntos
Quirópteros , Infecções por Coronavirus , Coronavirus , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Animais , Coronavirus/genética , Prevalência , Filogenia , Infecções por Coronavirus/epidemiologia
2.
Mol Ecol ; 32(14): 3989-4002, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37203872

RESUMO

Understanding the immunogenetic basis of coronavirus (CoV) susceptibility in major pathogen reservoirs, such as bats, is central to inferring their zoonotic potential. Members of the cryptic Hipposideros bat species complex differ in CoV susceptibility, but the underlying mechanisms remain unclear. The genes of the major histocompatibility complex (MHC) are the best understood genetic basis of pathogen resistance, and differences in MHC diversity are one possible reason for asymmetrical infection patterns among closely related species. Here, we aimed to link asymmetries in observed CoV (CoV-229E, CoV-2B and CoV-2Bbasal) susceptibility to immunogenetic differences amongst four Hipposideros bat species. From the 2072 bats assigned to their respective species using the mtDNA cytochrome b gene, members of the most numerous and ubiquitous species, Hipposideros caffer D, were most infected with CoV-229E and SARS-related CoV-2B. Using a subset of 569 bats, we determined that much of the existent allelic and functional (i.e. supertype) MHC DRB class II diversity originated from common ancestry. One MHC supertype shared amongst all species, ST12, was consistently linked to susceptibility with CoV-229E, which is closely related to the common cold agent HCoV-229E, and infected bats and those carrying ST12 had a lower body condition. The same MHC supertype was connected to resistance to CoV-2B, and bats with ST12 were less likely be co-infected with CoV-229E and CoV-2B. Our work suggests a role of immunogenetics in determining CoV susceptibility in bats. We advocate for the preservation of functional genetic and species diversity in reservoirs as a means of mitigating the risk of disease spillover.


Assuntos
Quirópteros , Coronavirus Humano 229E , Infecções por Coronavirus , Coronavirus , Animais , Quirópteros/genética , Genes MHC da Classe II , Filogenia , Coronavirus/genética , Coronavirus Humano 229E/genética , Antígenos de Histocompatibilidade Classe II/genética
3.
mBio ; 12(1)2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33468689

RESUMO

Bats host many viruses pathogenic to humans, and increasing evidence suggests that rotavirus A (RVA) also belongs to this list. Rotaviruses cause diarrheal disease in many mammals and birds, and their segmented genomes allow them to reassort and increase their genetic diversity. Eighteen out of 2,142 bat fecal samples (0.8%) collected from Europe, Central America, and Africa were PCR-positive for RVA, and 11 of those were fully characterized using viral metagenomics. Upon contrasting their genomes with publicly available data, at least 7 distinct bat RVA genotype constellations (GCs) were identified, which included evidence of reassortments and 6 novel genotypes. Some of these constellations are spread across the world, whereas others appear to be geographically restricted. Our analyses also suggest that several unusual human and equine RVA strains might be of bat RVA origin, based on their phylogenetic clustering, despite various levels of nucleotide sequence identities between them. Although SA11 is one of the most widely used reference strains for RVA research and forms the backbone of a reverse genetics system, its origin remained enigmatic. Remarkably, the majority of the genotypes of SA11-like strains were shared with Gabonese bat RVAs, suggesting a potential common origin. Overall, our findings suggest an underexplored genetic diversity of RVAs in bats, which is likely only the tip of the iceberg. Increasing contact between humans and bat wildlife will further increase the zoonosis risk, which warrants closer attention to these viruses.IMPORTANCE The increased research on bat coronaviruses after severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) allowed the very rapid identification of SARS-CoV-2. This is an excellent example of the importance of knowing viruses harbored by wildlife in general, and bats in particular, for global preparedness against emerging viral pathogens. The current effort to characterize bat rotavirus strains from 3 continents sheds light on the vast genetic diversity of rotaviruses and also hints at a bat origin for several atypical rotaviruses in humans and animals, implying that zoonoses of bat rotaviruses might occur more frequently than currently realized.


Assuntos
Quirópteros/virologia , Infecções por Rotavirus/transmissão , Infecções por Rotavirus/virologia , Rotavirus/genética , Zoonoses/transmissão , Zoonoses/virologia , Animais , COVID-19/transmissão , COVID-19/virologia , Diarreia/virologia , Variação Genética , Genoma Viral , Genótipo , Cavalos , Humanos , Metagenômica , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Filogenia , SARS-CoV-2/isolamento & purificação
4.
Zootaxa ; 4577(1): zootaxa.4577.1.9, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-31715741

RESUMO

Several house bat specimens superficially resembling the white-bellied house bat Scotophilus leucogaster (Cretzschmar, 1830), were recently captured in southwestern Ethiopia and southern South Sudan. These S. cf. leucogaster differed from typical S. leucogaster by their slightly smaller size and ventral coloration, conforming instead with the original description of S. altilis Allen, 1914. Scotophilus altilis is an overlooked taxon known from the Blue Nile region in Sudan that is currently considered a junior synonym of S. leucogaster. Phylogenetic analysis of mitochondrial cytochrome b gene (cytb) sequences revealed S. cf. leucogaster as a sister clade to S. leucogaster with a genetic distance of ca. 10%. Comparative specimens of questionable S. nigritellus de Winton, 1899 from northwestern Ethiopia and a wing biopsy sample of another S. cf. leucogaster from western Kenya also fell within this clade. Sequence data from two nuclear markers (zfy and fgb7) corroborated the distinction of S. cf. leucogaster from S. leucogaster. Likewise, morphometric analysis of cranial data largely supported this distinction, as well as taxonomic affiliation with S. altilis based on comparison with the only available paratype specimen. The position of this paratype specimen within the new Scotophilus clade, inferred from analysis of a short fragment of cytb, confirmed its taxonomic identity. Based on the presented evidence, the overlooked East African taxon S. altilis should be resurrected as a full species within the genus Scotophilus.


Assuntos
Quirópteros , Animais , Etiópia , Genes Mitocondriais , Quênia , Filogenia
5.
Parasitology ; 145(14): 1959-1968, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29781415

RESUMO

Five of the 13 known species of Mammomonogamus have been described in members of the family Felidae, including domestic cats, making felids the most frequent hosts of Mammomonogamus. The occurrence of Mammomonogamus in felids is geographically scattered and information on the life cycle and other aspects of infections is lacking. The paucity of data opens the questions on possible conspecificity of some of the described species of Mammomonogamus and on the existence of possible reservoirs for infections in domestic cats in geographically isolated endemic foci of infection. To test such hypotheses, we compared sequences of mitochondrial and nuclear markers obtained from Mammomonogamus adults or eggs collected from domestic cats in three geographically distant localities. Based on morphology, geographic origin and site of infection, the worms examined can be referred to as Mammomonogamus ierei and Mammomonogamus auris. Phylogenetic analyses of both mitochondrial and ribosomal DNA markers showed monophyly of the genus Mammomonogamus and suggested the existence of at least two species in cats. Review of the literature, the existence of several species and the discontinuous geographic distribution of Mammomonogamus infections in domestic cats suggest an historical spillover of infection from wild reservoirs, presumably wild felids.


Assuntos
Animais Selvagens/parasitologia , Gatos/parasitologia , Reservatórios de Doenças/veterinária , Infecções por Strongylida/veterinária , Strongyloidea/classificação , Distribuição Animal , Animais , Animais Domésticos/parasitologia , DNA Mitocondrial/genética , DNA Ribossômico/genética , Reservatórios de Doenças/parasitologia , Felidae/parasitologia , Feminino , Geografia , Masculino , Filogenia , Strongyloidea/isolamento & purificação
6.
Sci Rep ; 8(1): 5933, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29651122

RESUMO

Strongylid nematodes in large terrestrial herbivores such as great apes, equids, elephants, and humans tend to occur in complex communities. However, identification of all species within strongylid communities using traditional methods based on coproscopy or single nematode amplification and sequencing is virtually impossible. High-throughput sequencing (HTS) technologies provide opportunities to generate large amounts of sequence data and enable analyses of samples containing a mixture of DNA from multiple species/genotypes. We designed and tested an HTS approach for strain-level identification of gastrointestinal strongylids using ITS-2 metabarcoding at the MiSeq Illumina platform in samples from two free-ranging non-human primate species inhabiting the same environment, but differing significantly in their host traits and ecology. Although we observed overlapping of particular haplotypes, overall the studied primate species differed in their strongylid nematode community composition. Using HTS, we revealed hidden diversity in the strongylid nematode communities in non-human primates, more than one haplotype was found in more than 90% of samples and coinfections of more than one putative species occurred in 80% of samples. In conclusion, the HTS approach on strongylid nematodes, preferably using fecal samples, represents a time and cost-efficient way of studying strongylid communities and provides a resolution superior to traditional approaches.


Assuntos
Código de Barras de DNA Taxonômico , Doenças dos Cavalos/genética , Infecções por Strongylida/genética , Estrongilídios/genética , Animais , Fezes/parasitologia , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Doenças dos Cavalos/parasitologia , Cavalos/genética , Cavalos/parasitologia , Sequências Repetitivas Dispersas/genética , Estrongilídios/classificação , Infecções por Strongylida/parasitologia , Simpatria
7.
Parasitol Res ; 117(4): 1013-1024, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29470712

RESUMO

Four species of Mammomonogamus are known from large African herbivores. A recent study demonstrated that a single Mammomonogamus species was shared by both western lowland gorillas (Gorilla gorilla gorilla) and African forest elephants (Loxodonta cyclotis) in Central African Republic, suggesting lower species diversity than previously described in literature. We examined more than 500 fecal samples collected from sympatric African forest elephants, western lowland gorillas, and African forest buffaloes (Syncerus caffer nanus) at four study sites across Central Africa and examined them by coproscopic methods to detect Mammomonogamus eggs, which were found at three of the study sites. Subsequently, sequences of 18S rDNA, 28S rDNA, and cox1 amplified from individual eggs were analyzed. Phylogenetic analyses of both nuclear and mitochondrial DNA revealed two clades: one formed by sequences originating from Gabonese buffaloes and the other comprising gorillas and elephants. The gorilla-elephant clade was further differentiated depending on the locality. We show the existence of at least two distinct species of Mammomonogamus, M. loxodontis in elephants and gorillas and M. nasicola in buffaloes. The available information on Mammomonogamus in African herbivores is reviewed.


Assuntos
Entamoeba/genética , Entamoeba/isolamento & purificação , Helmintíase Animal/parasitologia , Strongyloidea , Animais , Búfalos/parasitologia , Carboxipeptidases/genética , República Centro-Africana , DNA Mitocondrial/genética , DNA Ribossômico/genética , Elefantes/parasitologia , Fezes/parasitologia , Feminino , Gorilla gorilla/parasitologia , Herbivoria , Interações Hospedeiro-Parasita , Humanos , Masculino , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Strongyloidea/classificação , Strongyloidea/genética , Strongyloidea/isolamento & purificação
8.
Parasitology ; 144(8): 1016-1025, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28274296

RESUMO

Syngamid strongylids of the genus Mammomonogamus undoubtedly belong among the least known nematodes with apparent zoonotic potential and the real diversity of the genus remains hard to evaluate without extensive molecular data. Eggs of Mammomonogamus sp. are frequently found in feces of African forest elephants (Loxodonta cyclotis) and western lowland gorillas (Gorilla gorilla gorilla) in Dzanga-Sangha Protected Areas. Using sedimentation-based coproscopic techniques, we found the eggs of Mammomonogamus in 19·7% elephant and 54·1% gorilla fecal samples with 8-55 and 1-24 eggs per gram of fecal sediment for elephants and gorillas, respectively. We used a combination of light microscopy, scanning electron microscopy and analysis of cytochrome c oxidase subunit I (cox1) and a partial sequence of 18S rDNA isolated from single eggs to test the hypothesis of possible Mammomonogamus conspecificity in gorillas and elephants. Whereas 18S rDNA sequences were identical in both gorillas and elephants, we distinguished seven different haplotypes within the cox1. Two haplotypes were found in both gorillas and elephants suggesting sharing of Mammomonogamus. Assignment of the parasite to M. loxodontis is proposed. Provided sequences represent the first genomic data on Mammomonogamus spp.


Assuntos
Doenças dos Símios Antropoides/epidemiologia , Elefantes , Gorilla gorilla , Infecções por Strongylida/veterinária , Strongyloidea/fisiologia , Animais , Doenças dos Símios Antropoides/parasitologia , República Centro-Africana/epidemiologia , DNA de Helmintos/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Proteínas de Helminto/genética , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Masculino , Filogenia , Prevalência , RNA Ribossômico 18S/genética , Análise de Sequência de DNA/veterinária , Infecções por Strongylida/epidemiologia , Infecções por Strongylida/parasitologia , Strongyloidea/classificação , Strongyloidea/genética
9.
Malar J ; 15(1): 423, 2016 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-27543045

RESUMO

BACKGROUND: Habitat types can affect vector and pathogen distribution and transmission dynamics. The prevalence and genetic diversity of Plasmodium spp. in two eastern chimpanzee populations-Kalinzu Forest Reserve, Uganda and Issa Valley, Tanzania-inhabiting different habitat types was investigated. As a follow up study the effect of host sex and age on infections patterns in Kalinzu Forest Reserve chimpanzees was determined. METHODS: Molecular methods were employed to detect Plasmodium DNA from faecal samples collected from savanna-woodland (Issa Valley) and forest (Kalinzu Forest Reserve) chimpanzee populations. RESULTS: Based on a Cytochrome-b PCR assay, 32 out of 160 Kalinzu chimpanzee faecal samples were positive for Plasmodium DNA, whilst no positive sample was detected in 171 Issa Valley chimpanzee faecal samples. Sequence analysis revealed that previously known Laverania species (Plasmodium reichenowi, Plasmodium billbrayi and Plasmodium billcollinsi) are circulating in the Kalinzu chimpanzees. A significantly higher proportion of young individuals were tested positive for infections, and switching of Plasmodium spp. was reported in one individual. Amongst the positive individuals sampled more than once, the success of amplification of Plasmodium DNA from faeces varied over sampling time. CONCLUSION: The study showed marked differences in the prevalence of malaria parasites among free ranging chimpanzee populations living in different habitats. In addition, a clear pattern of Plasmodium infections with respect to host age was found. The results presented in this study contribute to understanding the ecological aspects underlying the malaria infections in the wild. Nevertheless, integrative long-term studies on vector abundance, Plasmodium diversity during different seasons between sites would provide more insight on the occurrence, distribution and ecology of these pathogens.


Assuntos
Malária/veterinária , Pan troglodytes , Plasmodium/isolamento & purificação , Doenças dos Primatas/epidemiologia , Doenças dos Primatas/parasitologia , Animais , Citocromos b/genética , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Fezes/parasitologia , Feminino , Malária/epidemiologia , Malária/parasitologia , Masculino , Plasmodium/classificação , Plasmodium/genética , Prevalência , Proteínas de Protozoários/genética , Análise de Sequência de DNA , Tanzânia/epidemiologia , Uganda/epidemiologia
10.
Sci Rep ; 6: 26637, 2016 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-27217069

RESUMO

Crimean Congo hemorrhagic fever virus (CCHFV) is a highly virulent tick-borne pathogen that causes hemorrhagic fever in humans. The geographic range of human CCHF cases largely reflects the presence of ticks. However, highly similar CCHFV lineages occur in geographically distant regions. Tick-infested migratory birds have been suggested, but not confirmed, to contribute to the dispersal. Bats have recently been shown to carry nairoviruses distinct from CCHFV. In order to assess the presence of CCHFV in a wide range of bat species over a wide geographic range, we analyzed 1,135 sera from 16 different bat species collected in Congo, Gabon, Ghana, Germany, and Panama. Using a CCHFV glycoprotein-based indirect immunofluorescence test (IIFT), we identified reactive antibodies in 10.0% (114/1,135) of tested bats, pertaining to 12/16 tested species. Depending on the species, 3.6%-42.9% of cave-dwelling bats and 0.6%-7.1% of foliage-living bats were seropositive (two-tailed t-test, p = 0.0447 cave versus foliage). 11/30 IIFT-reactive sera from 10 different African bat species had neutralizing activity in a virus-like particle assay. Neutralization of full CCHFV was confirmed in 5 of 7 sera. Widespread infection of cave-dwelling bats may indicate a role for bats in the life cycle and geographic dispersal of CCHFV.


Assuntos
Quirópteros , Vírus da Febre Hemorrágica da Crimeia-Congo , Febre Hemorrágica da Crimeia , África Central/epidemiologia , Animais , Quirópteros/sangue , Quirópteros/virologia , Alemanha/epidemiologia , Febre Hemorrágica da Crimeia/sangue , Febre Hemorrágica da Crimeia/epidemiologia , Humanos , Panamá/epidemiologia
11.
Proc Natl Acad Sci U S A ; 112(49): 15190-5, 2015 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-26575627

RESUMO

Hepatitis A virus (HAV) is an ancient and ubiquitous human pathogen recovered previously only from primates. The sole species of the genus Hepatovirus, existing in both enveloped and nonenveloped forms, and with a capsid structure intermediate between that of insect viruses and mammalian picornaviruses, HAV is enigmatic in its origins. We conducted a targeted search for hepatoviruses in 15,987 specimens collected from 209 small mammal species globally and discovered highly diversified viruses in bats, rodents, hedgehogs, and shrews, which by pairwise sequence distance comprise 13 novel Hepatovirus species. Near-complete genomes from nine of these species show conservation of unique hepatovirus features, including predicted internal ribosome entry site structure, a truncated VP4 capsid protein lacking N-terminal myristoylation, a carboxyl-terminal pX extension of VP1, VP2 late domains involved in membrane envelopment, and a cis-acting replication element within the 3D(pol) sequence. Antibodies in some bat sera immunoprecipitated and neutralized human HAV, suggesting conservation of critical antigenic determinants. Limited phylogenetic cosegregation among hepatoviruses and their hosts and recombination patterns are indicative of major hepatovirus host shifts in the past. Ancestral state reconstructions suggest a Hepatovirus origin in small insectivorous mammals and a rodent origin of human HAV. Patterns of infection in small mammals mimicked those of human HAV in hepatotropism, fecal shedding, acute nature, and extinction of the virus in a closed host population. The evolutionary conservation of hepatovirus structure and pathogenesis provide novel insight into the origins of HAV and highlight the utility of analyzing animal reservoirs for risk assessment of emerging viruses.


Assuntos
Evolução Biológica , Vírus da Hepatite A/genética , Mamíferos/virologia , Animais , Humanos , Dados de Sequência Molecular , Filogenia
12.
J Virol ; 89(23): 11858-70, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26378164

RESUMO

UNLABELLED: We previously showed that close relatives of human coronavirus 229E (HCoV-229E) exist in African bats. The small sample and limited genomic characterizations have prevented further analyses so far. Here, we tested 2,087 fecal specimens from 11 bat species sampled in Ghana for HCoV-229E-related viruses by reverse transcription-PCR (RT-PCR). Only hipposiderid bats tested positive. To compare the genetic diversity of bat viruses and HCoV-229E, we tested historical isolates and diagnostic specimens sampled globally over 10 years. Bat viruses were 5- and 6-fold more diversified than HCoV-229E in the RNA-dependent RNA polymerase (RdRp) and spike genes. In phylogenetic analyses, HCoV-229E strains were monophyletic and not intermixed with animal viruses. Bat viruses formed three large clades in close and more distant sister relationships. A recently described 229E-related alpaca virus occupied an intermediate phylogenetic position between bat and human viruses. According to taxonomic criteria, human, alpaca, and bat viruses form a single CoV species showing evidence for multiple recombination events. HCoV-229E and the alpaca virus showed a major deletion in the spike S1 region compared to all bat viruses. Analyses of four full genomes from 229E-related bat CoVs revealed an eighth open reading frame (ORF8) located at the genomic 3' end. ORF8 also existed in the 229E-related alpaca virus. Reanalysis of HCoV-229E sequences showed a conserved transcription regulatory sequence preceding remnants of this ORF, suggesting its loss after acquisition of a 229E-related CoV by humans. These data suggested an evolutionary origin of 229E-related CoVs in hipposiderid bats, hypothetically with camelids as intermediate hosts preceding the establishment of HCoV-229E. IMPORTANCE: The ancestral origins of major human coronaviruses (HCoVs) likely involve bat hosts. Here, we provide conclusive genetic evidence for an evolutionary origin of the common cold virus HCoV-229E in hipposiderid bats by analyzing a large sample of African bats and characterizing several bat viruses on a full-genome level. Our evolutionary analyses show that animal and human viruses are genetically closely related, can exchange genetic material, and form a single viral species. We show that the putative host switches leading to the formation of HCoV-229E were accompanied by major genomic changes, including deletions in the viral spike glycoprotein gene and loss of an open reading frame. We reanalyze a previously described genetically related alpaca virus and discuss the role of camelids as potential intermediate hosts between bat and human viruses. The evolutionary history of HCoV-229E likely shares important characteristics with that of the recently emerged highly pathogenic Middle East respiratory syndrome (MERS) coronavirus.


Assuntos
Evolução Biológica , Quirópteros/virologia , Coronavirus Humano 229E/genética , Variação Genética , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Camelídeos Americanos/virologia , Primers do DNA/genética , Fezes/virologia , Gana , Humanos , Modelos Genéticos , Dados de Sequência Molecular , RNA Polimerase Dependente de RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Glicoproteína da Espícula de Coronavírus/genética
13.
Parasitology ; 142(10): 1278-89, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26046952

RESUMO

Anoplocephalid tapeworms of the genus Bertiella Stiles and Hassall, 1902 and Anoplocephala Blanchard, 1848, found in the Asian, African and American non-human primates are presumed to sporadic ape-to-man transmissions. Variable nuclear (5.8S-ITS2; 28S rRNA) and mitochondrial genes (cox1; nad1) of isolates of anoplocephalids originating from different primates (Callicebus oenanthe, Gorilla beringei, Gorilla gorilla, Pan troglodytes and Pongo abelii) and humans from various regions (South America, Africa, South-East Asia) were sequenced. In most analyses, Bertiella formed a monophyletic group within the subfamily Anoplocephalinae, however, the 28S rRNA sequence-based analysis indicated paraphyletic relationship between Bertiella from primates and Australian marsupials and rodents, which should thus be regarded as different taxa. Moreover, isolate determined as Anoplocephala cf. gorillae from mountain gorilla clustered within the Bertiella clade from primates. This either indicates that A. gorillae deserves to be included into the genus Bertiella, or, that an unknown Bertiella species infects also mountain gorillas. The analyses allowed the genetic differentiation of the isolates, albeit with no obvious geographical or host-related patterns. The unexpected genetic diversity of the isolates studied suggests the existence of several Bertiella species in primates and human and calls for revision of the whole group, based both on molecular and morphological data.


Assuntos
Cestoides/classificação , Cestoides/genética , Filogenia , Primatas/parasitologia , África , Animais , Sudeste Asiático , DNA Espaçador Ribossômico/genética , Genes Mitocondriais/genética , Variação Genética , Humanos , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , América do Sul , Especificidade da Espécie
14.
BMC Res Notes ; 7: 607, 2014 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-25189128

RESUMO

BACKGROUND: Noack's leaf-nosed bat, Hipposideros ruber, is a cryptic species within the Hipposideros caffer species complex. Despite a widespread distribution in Africa and being host to potentially zoonotic viruses, the genetic structure and ecology of H. ruber is poorly known. Here we describe the development of 11 novel polymorphic microsatellite loci to facilitate the investigation of genetic structure. FINDINGS: We selected 20 microsatellite sequences identified from high throughput sequence reads and PCR amplified these for 38 individuals, yielding 11 consistently amplifying and scorable loci. The number of alleles per locus ranged from two to 12, and observed heterozygosities from 0.00 to 0.865. No evidence of linkage disequilibrium was observed, and nine of the markers showed no departure from Hardy-Weinberg equilibrium. We demonstrate successful amplification in two closely related species and two divergent lineages of the H. caffer species complex. CONCLUSIONS: These new markers will provide a valuable tool to investigate genetic structure in the poorly understood Hipposideros caffer species complex.


Assuntos
Quirópteros/genética , Repetições de Microssatélites/genética , Animais , Sequência de Bases , Primers do DNA , Heterozigoto , Dados de Sequência Molecular
15.
PLoS One ; 9(6): e100172, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24959855

RESUMO

The rising incidence of emerging infectious diseases (EID) is mostly linked to biodiversity loss, changes in habitat use and increasing habitat fragmentation. Bats are linked to a growing number of EID but few studies have explored the factors of viral richness in bats. These may have implications for role of bats as potential reservoirs. We investigated the determinants of viral richness in 15 species of African bats (8 Pteropodidae and 7 microchiroptera) in Central and West Africa for which we provide new information on virus infection and bat phylogeny. We performed the first comparative analysis testing the correlation of the fragmented geographical distribution (defined as the perimeter to area ratio) with viral richness in bats. Because of their potential effect, sampling effort, host body weight, ecological and behavioural traits such as roosting behaviour, migration and geographical range, were included into the analysis as variables. The results showed that the geographical distribution size, shape and host body weight have significant effects on viral richness in bats. Viral richness was higher in large-bodied bats which had larger and more fragmented distribution areas. Accumulation of viruses may be related to the historical expansion and contraction of bat species distribution range, with potentially strong effects of distribution edges on virus transmission. Two potential explanations may explain these results. A positive distribution edge effect on the abundance or distribution of some bat species could have facilitated host switches. Alternatively, parasitism could play a direct role in shaping the distribution range of hosts through host local extinction by virulent parasites. This study highlights the importance of considering the fragmentation of bat species geographical distribution in order to understand their role in the circulation of viruses in Africa.


Assuntos
Biodiversidade , Quirópteros/virologia , Reservatórios de Doenças/veterinária , Vírus/isolamento & purificação , África , Animais , Quirópteros/classificação , Doenças Transmissíveis Emergentes/transmissão , Citocromos b/genética , Geografia , Filogenia , Densidade Demográfica , Dinâmica Populacional
16.
Proc Natl Acad Sci U S A ; 110(40): 16151-6, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24043818

RESUMO

The hepatitis B virus (HBV), family Hepadnaviridae, is one of most relevant human pathogens. HBV origins are enigmatic, and no zoonotic reservoirs are known. Here, we screened 3,080 specimens from 54 bat species representing 11 bat families for hepadnaviral DNA. Ten specimens (0.3%) from Panama and Gabon yielded unique hepadnaviruses in coancestral relation to HBV. Full genome sequencing allowed classification as three putative orthohepadnavirus species based on genome lengths (3,149-3,377 nt), presence of middle HBV surface and X-protein genes, and sequence distance criteria. Hepatic tropism in bats was shown by quantitative PCR and in situ hybridization. Infected livers showed histopathologic changes compatible with hepatitis. Human hepatocytes transfected with all three bat viruses cross-reacted with sera against the HBV core protein, concordant with the phylogenetic relatedness of these hepadnaviruses and HBV. One virus from Uroderma bilobatum, the tent-making bat, cross-reacted with monoclonal antibodies against the HBV antigenicity determining S domain. Up to 18.4% of bat sera contained antibodies against bat hepadnaviruses. Infectious clones were generated to study all three viruses in detail. Hepatitis D virus particles pseudotyped with surface proteins of U. bilobatum HBV, but neither of the other two viruses could infect primary human and Tupaia belangeri hepatocytes. Hepatocyte infection occurred through the human HBV receptor sodium taurocholate cotransporting polypeptide but could not be neutralized by sera from vaccinated humans. Antihepadnaviral treatment using an approved reverse transcriptase inhibitor blocked replication of all bat hepadnaviruses. Our data suggest that bats may have been ancestral sources of primate hepadnaviruses. The observed zoonotic potential might affect concepts aimed at eradicating HBV.


Assuntos
Quirópteros/virologia , Hepadnaviridae/genética , Hepadnaviridae/patogenicidade , Zoonoses/virologia , Animais , Sequência de Bases , Linhagem Celular Tumoral , Reações Cruzadas/imunologia , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Genoma/genética , Vírus da Hepatite B/genética , Hepatócitos/virologia , Humanos , Immunoblotting , Hibridização In Situ , Dados de Sequência Molecular , Análise de Sequência de DNA , Especificidade da Espécie , Tupaiidae
18.
Am J Phys Anthropol ; 148(4): 525-33, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22576323

RESUMO

The entodiniomorphid ciliate Troglodytella abrassarti is a colonic mutualist of great apes. Its host specificity makes it a suitable model for studies of primate evolution. We explored molecular diversity of T. abrassarti with regard to large geographical distribution and taxonomic diversity of its most common host, the chimpanzee. We found a very low diversification of T. abrassarti in chimpanzees across Africa. Distribution of two types of T. abrassarti supports evolutionary separation of the Western chimpanzee, P. t. verus, from populations in Central and East Africa. Type I T. abrassarti is probably a derived form, which corresponds with the Central African origin of chimpanzees and a founder event leading to P. t. verus. Exclusivity of the respective types of T. abrassarti to Western and Central/Eastern chimpanzees corroborates the difference found between an introduced population of presumed Western chimpanzees on Rubondo Island and an autochthonous population in mainland Tanzania. The identity of T. abrassarti from Nigerian P. t. ellioti and Central African chimpanzees suggests their close evolutionary relationship. Although this contrasts with published mtDNA data, it corroborates current opinion on the exclusive position of P. t. verus within the chimpanzee phylogeny. The type of T. abrassarti occurring in Central and East African common chimpanzee was confirmed also in bonobos. This may point to the presence of an ancestral Type II found throughout the Lower Guinean rainforest dating back to the common Pan ancestor. Alternatively, the molecular uniformity of T. abrassarti may imply a historical overlap of the species' distribution ranges.


Assuntos
Infecções por Cilióforos/veterinária , Cilióforos/genética , Evolução Molecular , Pan troglodytes/genética , Pan troglodytes/parasitologia , África Subsaariana , Animais , Infecções por Cilióforos/genética , Infecções por Cilióforos/parasitologia , Análise por Conglomerados , DNA de Protozoário/análise , Fezes/parasitologia , Variação Genética , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Especificidade da Espécie , Simbiose/genética
19.
Nat Commun ; 3: 796, 2012 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-22531181

RESUMO

The large virus family Paramyxoviridae includes some of the most significant human and livestock viruses, such as measles-, distemper-, mumps-, parainfluenza-, Newcastle disease-, respiratory syncytial virus and metapneumoviruses. Here we identify an estimated 66 new paramyxoviruses in a worldwide sample of 119 bat and rodent species (9,278 individuals). Major discoveries include evidence of an origin of Hendra- and Nipah virus in Africa, identification of a bat virus conspecific with the human mumps virus, detection of close relatives of respiratory syncytial virus, mouse pneumonia- and canine distemper virus in bats, as well as direct evidence of Sendai virus in rodents. Phylogenetic reconstruction of host associations suggests a predominance of host switches from bats to other mammals and birds. Hypothesis tests in a maximum likelihood framework permit the phylogenetic placement of bats as tentative hosts at ancestral nodes to both the major Paramyxoviridae subfamilies (Paramyxovirinae and Pneumovirinae). Future attempts to predict the emergence of novel paramyxoviruses in humans and livestock will have to rely fundamentally on these data.


Assuntos
Quirópteros/virologia , Reservatórios de Doenças/virologia , Mamíferos/virologia , Infecções por Paramyxoviridae/virologia , Paramyxoviridae/classificação , Paramyxoviridae/isolamento & purificação , Animais , Cães , Humanos , Camundongos , Dados de Sequência Molecular , Paramyxoviridae/genética , Filogenia
20.
J Virol ; 84(21): 11336-49, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20686038

RESUMO

Bats may host emerging viruses, including coronaviruses (CoV). We conducted an evaluation of CoV in rhinolophid and vespertilionid bat species common in Europe. Rhinolophids carried severe acute respiratory syndrome (SARS)-related CoV at high frequencies and concentrations (26% of animals are positive; up to 2.4×10(8) copies per gram of feces), as well as two Alphacoronavirus clades, one novel and one related to the HKU2 clade. All three clades present in Miniopterus bats in China (HKU7, HKU8, and 1A related) were also present in European Miniopterus bats. An additional novel Alphacoronavirus clade (bat CoV [BtCoV]/BNM98-30) was detected in Nyctalus leisleri. A CoV grouping criterion was developed by comparing amino acid identities across an 816-bp fragment of the RNA-dependent RNA polymerases (RdRp) of all accepted mammalian CoV species (RdRp-based grouping units [RGU]). Criteria for defining separate RGU in mammalian CoV were a >4.8% amino acid distance for alphacoronaviruses and a >6.3% distance for betacoronaviruses. All the above-mentioned novel clades represented independent RGU. Strict associations between CoV RGU and host bat genera were confirmed for six independent RGU represented simultaneously in China and Europe. A SARS-related virus (BtCoV/BM48-31/Bulgaria/2008) from a Rhinolophus blasii (Rhi bla) bat was fully sequenced. It is predicted that proteins 3b and 6 were highly divergent from those proteins in all known SARS-related CoV. Open reading frame 8 (ORF8) was surprisingly absent. Surface expression of spike and staining with sera of SARS survivors suggested low antigenic overlap with SARS CoV. However, the receptor binding domain of SARS CoV showed higher similarity with that of BtCoV/BM48-31/Bulgaria/2008 than with that of any Chinese bat-borne CoV. Critical spike domains 472 and 487 were identical and similar, respectively. This study underlines the importance of assessments of the zoonotic potential of widely distributed bat-borne CoV.


Assuntos
Quirópteros/virologia , Coronavirus/classificação , Genoma Viral/genética , RNA Polimerase Dependente de RNA/genética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Animais , Sequência de Bases , China , Europa (Continente) , Humanos
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