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A M Polderman - One of the best experts on this subject based on the ideXlab platform.
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oesophagostomum bifurcum in non human primates is not a potential reservoir for human infection in ghana
Tropical Medicine & International Health, 2005Co-Authors: Lisette Van Lieshout, Johanna M De Gruijter, Michael Adunsiah, Michael Haizel, Jaco J Verweij, Eric A T Brienen, Robin B Gasser, A M PoldermanAbstract:Summary In northern Togo and Ghana, human infection with the parasitic nematode Oesophagostomum bifurcum is of major health importance. Elsewhere, oesophagostomiasis is considered a zoonotic infection, non-human primates being the natural host. We examined 349 faecal samples of the olive baboon, Mona Monkey and black and white colobus Monkey from two geographically distinct areas in Ghana, outside the region endemic for O. bifurcum in humans. Using both microscopy and species-specific PCR, we found a high prevalence of O. bifurcum (75–99%) in olive baboons and Mona Monkeys. The majority of the test-positive faecal samples contained large numbers of larvae after copro-culture (>100). No O. bifurcum was detected in the faeces of the black and white colobus Monkeys. Observational studies on the behaviour of the non-human primates, focusing on defecation, food consumption and the sharing of habitat with the local human population, indicated favourable conditions for zoonotic transmission. Given that no human infection with O. bifurcum has been reported from either study area, the present findings support the hypothesis that O. bifurcum from humans in the north of Ghana, and O. bifurcum from olive baboons and/or Mona Monkeys are distinct.
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definition of genetic markers in nuclear ribosomal dna for a neglected parasite of primates ternidens deminutus nematoda strongylida diagnostic and epidemiological implications
Parasitology, 2005Co-Authors: A R Schindler, A M Polderman, J M De Gruijter, Robin B GasserAbstract:Ternidens deminutus (Strongylida) is a parasitic nematode infecting non-human and human primates in parts of Africa, Asia and the Pacific islands. The present study genetically characterized T. deminutus and defined genetic markers in nuclear ribosomal DNA (rDNA) as a basis for developing molecular-diagnostic tools. The sequences of the second internal transcribed spacer (ITS-2) of rDNA were determined for adult specimens of T. deminutus (Nematoda: Strongylida: Oesophagostominae) from the Olive baboon and the Mona Monkey.Nucleotide sequence data used in this paper are available in the EMBL, GenBank and DDJB databases under the Accession nos. AJ888729, AJ888730, AF136576, Y10789, Y10790, Y11733, Y11735, Y11736, AJ001594, AJ001599, AJ006149 and AJ006150. The former 2 sequences represent original data reported in this paper. The length and G+C content of the ITS-2 sequences was 216 bp and ~43%, respectively. While there was no sequence variation among individual T. deminutus specimens from the baboon, 6 (2·8%) nucleotide differences were detected in the ITS-2 between the parasite from baboon and that of the Mona Monkey, which is similar to the difference (3·2%) between 2 other species of Oesophagostominae (Oesophagostomum bifurcum and O. stephanostomum) from non-human primates, suggesting significant population variation or the existence of cryptic (i.e. hidden) species within T. deminutus. Pairwise comparisons of the ITS-2 sequences of the 2 operational taxonomic units of T. deminutus with previously published ITS-2 sequences for selected members of the subfamilies Oesophagostominae and Chabertiinae indicated that species from primates (including those representing the subgenera Conoweberia and Ihleia) are closely related, in accordance with previous morphological studies. The sequence differences (27–48·3%) in the ITS-2 between the 2 taxonomic units of T. deminutus and hookworms (superfamily Ancylostomatoidea) enabled their identification and delineation by polymerase chain reaction (PCR)-based mutation scanning. The genetic markers in the ITS-2 provide a foundation for improved, PCR-based diagnosis of T. deminutus infections and for investigating the life-cycle, transmission patterns and ecology of this parasite.
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high resolution dna fingerprinting by aflp to study the genetic variation among oesophagostomum bifurcum nematoda from human and non human primates from ghana
Parasitology, 2005Co-Authors: Johanna M De Gruijter, A M Polderman, Robin B Gasser, V Asigri, Lenie DijkshoornAbstract:: An AFLP approach was established to investigate genetic diversity within Oesophagostomum bifurcum (order Strongylida) from human and non-human primates. Evaluation of different combinations of restriction enzymes (n = 8) and primers (n = 29) demonstrated that the use of HindIII/BglII digested templates and primers with the selective nucleotides + AG/ +AC, respectively, was the most effective for the analysis of O. bifurcum DNA. A total of 63 O. bifurcum adults from human, Patas Monkey, Mona Monkey and Olive baboon hosts from different geographical regions in Ghana were subjected to analysis using this method. Cluster analysis revealed 4 genetically distinct groups, namely O. bifurcum from the Patas Monkey (I), from the Mona Monkey (II), from humans (III) and from the Olive baboon (IV). These findings were concordant with those achieved previously using RAPD analysis and supports population genetic substructuring within O. bifurcum according to host species. The results demonstrated the effectiveness of the present AFLP method for establishing genetic variation within O. bifurcum, and indicates its applicability to other parasitic nematodes of human and/or veterinary health importance.
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genetic substructuring within oesophagostomum bifurcum nematoda from human and non human primates from ghana based on random amplified polymorphic dna analysis
American Journal of Tropical Medicine and Hygiene, 2004Co-Authors: Johanna M De Gruijter, A M Polderman, Jaco J Verweij, Juventus B Ziem, Robin B GasserAbstract:Random amplified polymorphic DNA (RAPD) was used to study genetic variation within Oesophagostomum bifurcum in Ghana. Four different decamer primers were used for the amplification of DNA from individual O. bifurcum adults (n = 41) from humans and non-human primates (including the Mona Monkey, Patas Monkey and Olive baboon) from different geographic regions. Analysis of the amplicons from all 41 nematodes by high resolution, denaturing polyacrylamide gel electrophoresis defined a total of 326 informative RAPD bands. Cluster analysis of the RAPD data (based on pairwise comparison of banding profiles) showed that O. bifurcum from humans was genetically distinct from O. bifurcum from the Mona and Patas Monkeys, and from the Olive baboon. These findings clearly demonstrate the existence of population genetic substructuring within O. bifurcum from different primate hosts in Ghana, and raise interesting questions about host specificity, epidemiology (e.g., zoonotic transmission), and ecology of the different genotypes of O. bifurcum.
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screening for haplotypic variability within oesophagostomum bifurcum nematoda employing a single strand conformation polymorphism approach
Molecular and Cellular Probes, 2002Co-Authors: Johanna M De Gruijter, A M PoldermanAbstract:Abstract Genetic markers in the mitochondrial genome have proven useful for population genetic studies because of their maternal inheritance and relatively high evolutionary rates. In this study, we exploited the high resolution capacity of PCR-coupled single-strand conformation polymorphism (SSCP) to screen for sequence variation in part of the cytochrome c oxidase subunit 1 gene (p cox 1) among individuals of the parasitic nematode, Oesophagostomum bifurcum from human or Mona Monkey hosts from Africa. SSCP analysis revealed distinct profiles among some of the individuals, and subsequent sequence analysis of representative samples defined 10 different haplotypes. For comparative purposes, the p cox 1 sequences for representatives of four other species of Oesophagostomum from livestock were included. While there were high levels (11·5–13·7%) of sequence difference among the latter species, there was no fixed nucleotide difference between O. bifurcum individuals from humans and those from Monkeys. The data support the proposal that O. bifurcum from the two primate hosts represents a single species and that the haplotypic variability in p cox 1 represents population variation. The results reinforce the usefulness of the SSCP-sequencing approach for studying genetic variation in nematode populations using mitochondrial markers.
Adeniyi C Adeola - One of the best experts on this subject based on the ideXlab platform.
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population genomics reveals incipient speciation introgression and adaptation in the african Mona Monkey cercopithecus Mona
Molecular Biology and Evolution, 2021Co-Authors: Adeola Oluwakemi Ayoola, Baolin Zhang, Richard P Meisel, Lotanna M Nneji, Yong Shao, Olanrewaju B Morenikeji, Adeniyi C AdeolaAbstract:Guenons (tribe Cercopithecini) are the most widely distributed non-human primate in the tropical forest belt of Africa and show considerable phenotypic, taxonomic, and ecological diversity. However, genomic information for most species within this group is still lacking. Here, we present a high-quality de novo genome (total 2.90 Gb, contig N50 equal to 22.7 Mb) of the Mona Monkey (Cercopithecus Mona), together with genome resequencing data of 13 individuals sampled across Nigeria. Our results showed differentiation between populations from East and West of the Niger River ∼84 thousands years ago and potential ancient introgression in the East population from other Mona group species. The PTPRK, FRAS1, BNC2, and EDN3 genes related to pigmentation displayed signals of introgression in the East population. Genomic scans suggest that immunity genes such as AKT3 and IL13 (possibly involved in simian immunodeficiency virus defense), and G6PD, a gene involved in malaria resistance, are under positive natural selection. Our study gives insights into differentiation, natural selection and introgression in guenons.
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population genomics reveals incipient speciation introgression and adaptation in the african Mona Monkey cercopithecus Mona
Molecular Biology and Evolution, 2021Co-Authors: Adeola Oluwakemi Ayoola, Baolin Zhang, Richard P Meisel, Lotanna M Nneji, Yong Shao, Olanrewaju B Morenikeji, Adeniyi C AdeolaAbstract:Guenons (tribe Cercopithecini) are the most widely distributed nonhuman primate in the tropical forest belt of Africa and show considerable phenotypic, taxonomic, and ecological diversity. However, genomic information for most species within this group is still lacking. Here, we present a high-quality de novo genome (total 2.90 Gb, contig N50 equal to 22.7 Mb) of the Mona Monkey (Cercopithecus Mona), together with genome resequencing data of 13 individuals sampled across Nigeria. Our results showed differentiation between populations from East and West of the Niger River ∼84 ka and potential ancient introgression in the East population from other Mona group species. The PTPRK, FRAS1, BNC2, and EDN3 genes related to pigmentation displayed signals of introgression in the East population. Genomic scans suggest that immunity genes such as AKT3 and IL13 (possibly involved in simian immunodeficiency virus defense), and G6PD, a gene involved in malaria resistance, are under positive natural selection. Our study gives insights into differentiation, natural selection, and introgression in guenons.
Robin B Gasser - One of the best experts on this subject based on the ideXlab platform.
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oesophagostomum bifurcum in non human primates is not a potential reservoir for human infection in ghana
Tropical Medicine & International Health, 2005Co-Authors: Lisette Van Lieshout, Johanna M De Gruijter, Michael Adunsiah, Michael Haizel, Jaco J Verweij, Eric A T Brienen, Robin B Gasser, A M PoldermanAbstract:Summary In northern Togo and Ghana, human infection with the parasitic nematode Oesophagostomum bifurcum is of major health importance. Elsewhere, oesophagostomiasis is considered a zoonotic infection, non-human primates being the natural host. We examined 349 faecal samples of the olive baboon, Mona Monkey and black and white colobus Monkey from two geographically distinct areas in Ghana, outside the region endemic for O. bifurcum in humans. Using both microscopy and species-specific PCR, we found a high prevalence of O. bifurcum (75–99%) in olive baboons and Mona Monkeys. The majority of the test-positive faecal samples contained large numbers of larvae after copro-culture (>100). No O. bifurcum was detected in the faeces of the black and white colobus Monkeys. Observational studies on the behaviour of the non-human primates, focusing on defecation, food consumption and the sharing of habitat with the local human population, indicated favourable conditions for zoonotic transmission. Given that no human infection with O. bifurcum has been reported from either study area, the present findings support the hypothesis that O. bifurcum from humans in the north of Ghana, and O. bifurcum from olive baboons and/or Mona Monkeys are distinct.
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definition of genetic markers in nuclear ribosomal dna for a neglected parasite of primates ternidens deminutus nematoda strongylida diagnostic and epidemiological implications
Parasitology, 2005Co-Authors: A R Schindler, A M Polderman, J M De Gruijter, Robin B GasserAbstract:Ternidens deminutus (Strongylida) is a parasitic nematode infecting non-human and human primates in parts of Africa, Asia and the Pacific islands. The present study genetically characterized T. deminutus and defined genetic markers in nuclear ribosomal DNA (rDNA) as a basis for developing molecular-diagnostic tools. The sequences of the second internal transcribed spacer (ITS-2) of rDNA were determined for adult specimens of T. deminutus (Nematoda: Strongylida: Oesophagostominae) from the Olive baboon and the Mona Monkey.Nucleotide sequence data used in this paper are available in the EMBL, GenBank and DDJB databases under the Accession nos. AJ888729, AJ888730, AF136576, Y10789, Y10790, Y11733, Y11735, Y11736, AJ001594, AJ001599, AJ006149 and AJ006150. The former 2 sequences represent original data reported in this paper. The length and G+C content of the ITS-2 sequences was 216 bp and ~43%, respectively. While there was no sequence variation among individual T. deminutus specimens from the baboon, 6 (2·8%) nucleotide differences were detected in the ITS-2 between the parasite from baboon and that of the Mona Monkey, which is similar to the difference (3·2%) between 2 other species of Oesophagostominae (Oesophagostomum bifurcum and O. stephanostomum) from non-human primates, suggesting significant population variation or the existence of cryptic (i.e. hidden) species within T. deminutus. Pairwise comparisons of the ITS-2 sequences of the 2 operational taxonomic units of T. deminutus with previously published ITS-2 sequences for selected members of the subfamilies Oesophagostominae and Chabertiinae indicated that species from primates (including those representing the subgenera Conoweberia and Ihleia) are closely related, in accordance with previous morphological studies. The sequence differences (27–48·3%) in the ITS-2 between the 2 taxonomic units of T. deminutus and hookworms (superfamily Ancylostomatoidea) enabled their identification and delineation by polymerase chain reaction (PCR)-based mutation scanning. The genetic markers in the ITS-2 provide a foundation for improved, PCR-based diagnosis of T. deminutus infections and for investigating the life-cycle, transmission patterns and ecology of this parasite.
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high resolution dna fingerprinting by aflp to study the genetic variation among oesophagostomum bifurcum nematoda from human and non human primates from ghana
Parasitology, 2005Co-Authors: Johanna M De Gruijter, A M Polderman, Robin B Gasser, V Asigri, Lenie DijkshoornAbstract:: An AFLP approach was established to investigate genetic diversity within Oesophagostomum bifurcum (order Strongylida) from human and non-human primates. Evaluation of different combinations of restriction enzymes (n = 8) and primers (n = 29) demonstrated that the use of HindIII/BglII digested templates and primers with the selective nucleotides + AG/ +AC, respectively, was the most effective for the analysis of O. bifurcum DNA. A total of 63 O. bifurcum adults from human, Patas Monkey, Mona Monkey and Olive baboon hosts from different geographical regions in Ghana were subjected to analysis using this method. Cluster analysis revealed 4 genetically distinct groups, namely O. bifurcum from the Patas Monkey (I), from the Mona Monkey (II), from humans (III) and from the Olive baboon (IV). These findings were concordant with those achieved previously using RAPD analysis and supports population genetic substructuring within O. bifurcum according to host species. The results demonstrated the effectiveness of the present AFLP method for establishing genetic variation within O. bifurcum, and indicates its applicability to other parasitic nematodes of human and/or veterinary health importance.
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genetic substructuring within oesophagostomum bifurcum nematoda from human and non human primates from ghana based on random amplified polymorphic dna analysis
American Journal of Tropical Medicine and Hygiene, 2004Co-Authors: Johanna M De Gruijter, A M Polderman, Jaco J Verweij, Juventus B Ziem, Robin B GasserAbstract:Random amplified polymorphic DNA (RAPD) was used to study genetic variation within Oesophagostomum bifurcum in Ghana. Four different decamer primers were used for the amplification of DNA from individual O. bifurcum adults (n = 41) from humans and non-human primates (including the Mona Monkey, Patas Monkey and Olive baboon) from different geographic regions. Analysis of the amplicons from all 41 nematodes by high resolution, denaturing polyacrylamide gel electrophoresis defined a total of 326 informative RAPD bands. Cluster analysis of the RAPD data (based on pairwise comparison of banding profiles) showed that O. bifurcum from humans was genetically distinct from O. bifurcum from the Mona and Patas Monkeys, and from the Olive baboon. These findings clearly demonstrate the existence of population genetic substructuring within O. bifurcum from different primate hosts in Ghana, and raise interesting questions about host specificity, epidemiology (e.g., zoonotic transmission), and ecology of the different genotypes of O. bifurcum.
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screening for nucleotide variations in ribosomal dna arrays of oesophagostomum bifurcum by polymerase chain reaction coupled single strand conformation polymorphism
Electrophoresis, 1999Co-Authors: Robin B Gasser, Wayne G Woods, Jaco J Verweij, Coby Blotkamp, Philipe A Storey, A M PoldermanAbstract:: We exploited the high resolution capacity of polymerase chain reaction (PCR)-coupled single-strand conformation polymorphism (SSCP) to screen for sequence variation in the second internal transcribed spacer (ITS-2) of ribosomal DNA (rDNA) among 77 individuals representing Oesophagostumum bifurcum from human or Mona Monkey hosts from Africa. SSCP analysis revealed distinct profiles among some of the individuals, and sequence analysis of representative samples defined different ITS-2 sequence types attributable to polymorphism at particular nucleotide positions. However, there was no unequivocal sequence difference between O. bifurcum individuals from humans and that from Monkeys. This provided some support for the hypothesis that the parasite from the two hosts represents a single species and that the sequence microheterogeneity detected in the ITS-2 rDNA region represents population variation, although the findings were insufficient to reject the proposal that the parasite represents different species. Overall, the results showed the usefulness of the SSCP-sequencing approach for studying the genetic variation in O. bifurcum populations and indicated its potential to study macromolecular evolution and elucidate population differentiation at the molecular level.
Nathan D Wolfe - One of the best experts on this subject based on the ideXlab platform.
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genetic characterization of the complete genome of a highly divergent simian t lymphotropic virus stlv type 3 from a wild cercopithecus Mona Monkey
Retrovirology, 2009Co-Authors: David Sintasath, Nathan D Wolfe, Hao Qiang Zheng, Matthew Lebreton, Martine Peeters, Ubald Tamoufe, Cyrille F Djoko, Joseph Le Doux Diffo, Eitel MpoudingoleAbstract:Background The recent discoveries of novel human T-lymphotropic virus type 3 (HTLV-3) and highly divergent simian T-lymphotropic virus type 3 (STLV-3) subtype D viruses from two different Monkey species in southern Cameroon suggest that the diversity and cross-species transmission of these retroviruses are much greater than currently appreciated.
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Genetic characterization of the complete genome of a highly divergent simian T-lymphotropic virus (STLV) type 3 from a wild Cercopithecus Mona Monkey
Retrovirology, 2009Co-Authors: David Sintasath, Nathan D Wolfe, Hao Qiang Zheng, Matthew Lebreton, Martine Peeters, Ubald Tamoufe, Cyrille F Djoko, Joseph Le Doux Diffo, Eitel Mpoudi-ngole, Walid HeneineAbstract:Background The recent discoveries of novel human T-lymphotropic virus type 3 (HTLV-3) and highly divergent simian T-lymphotropic virus type 3 (STLV-3) subtype D viruses from two different Monkey species in southern Cameroon suggest that the diversity and cross-species transmission of these retroviruses are much greater than currently appreciated. Results We describe here the first full-length sequence of a highly divergent STLV-3d(Cmo8699AB) virus obtained by PCR-based genome walking using DNA from two dried blood spots (DBS) collected from a wild-caught Cercopithecus Mona Monkey. The genome of STLV-3d(Cmo8699AB) is 8913-bp long and shares only 77% identity to other PTLV-3s. Phylogenetic analyses using Bayesian and maximum likelihood inference clearly show that this highly divergent virus forms an independent lineage with high posterior probability and bootstrap support within the diversity of PTLV-3. Molecular dating of concatenated gag-pol-env-tax sequences inferred a divergence date of about 115,117 years ago for STLV-3d(Cmo8699AB) indicating an ancient origin for this newly identified lineage. Major structural, enzymatic, and regulatory gene regions of STLV-3d(Cmo8699AB) are intact and suggest viral replication and a predicted pathogenic potential comparable to other PTLV-3s. Conclusion When taken together, the inferred ancient origin of STLV-3d(Cmo8699AB), the presence of this highly divergent virus in two primate species from the same geographical region, and the ease with which STLVs can be transmitted across species boundaries all suggest that STLV-3d may be more prevalent and widespread. Given the high human exposure to nonhuman primates in this region and the unknown pathogenicity of this divergent PTLV-3, increased surveillance and expanded prevention activities are necessary. Our ability to obtain the complete viral genome from DBS also highlights further the utility of this method for molecular-based epidemiologic studies.
David Sintasath - One of the best experts on this subject based on the ideXlab platform.
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genetic characterization of the complete genome of a highly divergent simian t lymphotropic virus stlv type 3 from a wild cercopithecus Mona Monkey
Retrovirology, 2009Co-Authors: David Sintasath, Nathan D Wolfe, Hao Qiang Zheng, Matthew Lebreton, Martine Peeters, Ubald Tamoufe, Cyrille F Djoko, Joseph Le Doux Diffo, Eitel MpoudingoleAbstract:Background The recent discoveries of novel human T-lymphotropic virus type 3 (HTLV-3) and highly divergent simian T-lymphotropic virus type 3 (STLV-3) subtype D viruses from two different Monkey species in southern Cameroon suggest that the diversity and cross-species transmission of these retroviruses are much greater than currently appreciated.
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Genetic characterization of the complete genome of a highly divergent simian T-lymphotropic virus (STLV) type 3 from a wild Cercopithecus Mona Monkey
Retrovirology, 2009Co-Authors: David Sintasath, Nathan D Wolfe, Hao Qiang Zheng, Matthew Lebreton, Martine Peeters, Ubald Tamoufe, Cyrille F Djoko, Joseph Le Doux Diffo, Eitel Mpoudi-ngole, Walid HeneineAbstract:Background The recent discoveries of novel human T-lymphotropic virus type 3 (HTLV-3) and highly divergent simian T-lymphotropic virus type 3 (STLV-3) subtype D viruses from two different Monkey species in southern Cameroon suggest that the diversity and cross-species transmission of these retroviruses are much greater than currently appreciated. Results We describe here the first full-length sequence of a highly divergent STLV-3d(Cmo8699AB) virus obtained by PCR-based genome walking using DNA from two dried blood spots (DBS) collected from a wild-caught Cercopithecus Mona Monkey. The genome of STLV-3d(Cmo8699AB) is 8913-bp long and shares only 77% identity to other PTLV-3s. Phylogenetic analyses using Bayesian and maximum likelihood inference clearly show that this highly divergent virus forms an independent lineage with high posterior probability and bootstrap support within the diversity of PTLV-3. Molecular dating of concatenated gag-pol-env-tax sequences inferred a divergence date of about 115,117 years ago for STLV-3d(Cmo8699AB) indicating an ancient origin for this newly identified lineage. Major structural, enzymatic, and regulatory gene regions of STLV-3d(Cmo8699AB) are intact and suggest viral replication and a predicted pathogenic potential comparable to other PTLV-3s. Conclusion When taken together, the inferred ancient origin of STLV-3d(Cmo8699AB), the presence of this highly divergent virus in two primate species from the same geographical region, and the ease with which STLVs can be transmitted across species boundaries all suggest that STLV-3d may be more prevalent and widespread. Given the high human exposure to nonhuman primates in this region and the unknown pathogenicity of this divergent PTLV-3, increased surveillance and expanded prevention activities are necessary. Our ability to obtain the complete viral genome from DBS also highlights further the utility of this method for molecular-based epidemiologic studies.