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Further characterisation of Haemocystidium chelodinae-like Haemoproteidae isolated from the Bellinger River snapping turtle (Myuchelys georgesi). Parasitol Res 2019; 119:601-609. [PMID: 31754857 DOI: 10.1007/s00436-019-06547-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 11/06/2019] [Indexed: 10/25/2022]
Abstract
The Bellinger River snapping turtle (Myuchelys georgesi) is endemic to Australia and is confined to a highly restricted distribution in the Bellinger River in New South Wales. Routine veterinary health examinations of 17 healthy turtles were undertaken, along with the collection and analysis of blood samples, during conservation efforts to save the species following a catastrophic population decline. Microscopy analysis of blood films detected Haemoproteidae parasites that morphologically resembled Haemocystidium chelodinae inside turtle erythrocytes. Of the 17 turtles examined, 16 were positive for infection with H. chelodinae by both light microscopy and PCR. DNA sequencing of a partial fragment of the mitochondrial cytochrome b (cytb) gene and phylogenetic analysis identified two different H. chelodinae-like genotypes. The phylogenetic relationship of H. chelodinae-like to other Haemoproteidae species based on cytb sequences grouped H. chelodinae-like into the reptile clade, but revealed the Haemocystidium genus to be paraphyletic as the clade also contained Haemoproteus, thus supporting a re-naming of Haemoproteus species from reptiles to Haemocystidium species. This study reports for the first time the genetic characterisation of H. chelodinae-like organisms isolated from a new Testudine host species, the Bellinger River snapping turtle. As evidence grows, further research will be necessary to understand the mode of transmission and to investigate whether these parasites are pathogenic to their hosts.
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Abstract
Morphological and molecular techniques were used to investigate the presence of hemogregarines and haemosporidians in biological samples of free-living Geoffroy's side-necked turtles (Phrynops geoffroanus) and Giant Amazon turtles (Podocnemis expansa) from Brazil. No evolutionary form of haemosporidians or hemogregarines were observed in the blood smears of 83 P. geoffroanus samples, and there were no meronts in the histological sections of 31 necropsied P. geoffroanus samples. All DNA samples extracted from P. geoffroanus tissues and blood aliquots were negative in haemosporidian PCR assays (based on the mitochondrial cytochrome b gene) and hemogregarine PCR assays (based on the 18S rRNA gene). In the analysis of blood smears of all seven Podocnemis expansa evaluated, gametocytes of hemogregarines were observed. The seven P. expansa were negative in the haemosporidian PCR assays. Moreover, hemogregarine DNA was detected in blood samples from all of the sampled P. expansa. The phylogenetic maximum likelihood inference and probabilistic Bayesian inference revealed five closely related genotypes that formed a monophyletic group. There was also a sister group to the lineage that consisted of Haemogregarina spp. of freshwater turtles from Canada, Italy, Mozambique, Kenya, Gabon, Vietnam, and China. The findings suggest that free-living P. expansa were parasitized by a new genotype or even a possible new species of the genus Haemogregarina. Haemosporidians and hemogregarines are not frequently found in P. geoffroanus in the studied region under the local conditions of that period.
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Oliveira JPD, André MR, Alves Júnior JRF, Lustosa APG, Werther K. Molecular detection of hemogregarines and haemosporidians in Brazilian free-living testudines. INTERNATIONAL JOURNAL FOR PARASITOLOGY-PARASITES AND WILDLIFE 2018; 7:75-84. [PMID: 30050752 PMCID: PMC6058349 DOI: 10.1016/j.ijppaw.2018.01.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 12/11/2017] [Accepted: 01/24/2018] [Indexed: 12/21/2022]
Abstract
Morphological and molecular techniques were used to investigate the presence of hemogregarines and haemosporidians in biological samples of free-living Geoffroy's side-necked turtles (Phrynops geoffroanus) and Giant Amazon turtles (Podocnemis expansa) from Brazil. No evolutionary form of haemosporidians or hemogregarines were observed in the blood smears of 83 P. geoffroanus samples, and there were no meronts in the histological sections of 31 necropsied P. geoffroanus samples. All DNA samples extracted from P. geoffroanus tissues and blood aliquots were negative in haemosporidian PCR assays (based on the mitochondrial cytochrome b gene) and hemogregarine PCR assays (based on the 18S rRNA gene). In the analysis of blood smears of all seven Podocnemis expansa evaluated, gametocytes of hemogregarines were observed. The seven P. expansa were negative in the haemosporidian PCR assays. Moreover, hemogregarine DNA was detected in blood samples from all of the sampled P. expansa. The phylogenetic maximum likelihood inference and probabilistic Bayesian inference revealed five closely related genotypes that formed a monophyletic group. There was also a sister group to the lineage that consisted of Haemogregarina spp. of freshwater turtles from Canada, Italy, Mozambique, Kenya, Gabon, Vietnam, and China. The findings suggest that free-living P. expansa were parasitized by a new genotype or even a possible new species of the genus Haemogregarina. Haemosporidians and hemogregarines are not frequently found in P. geoffroanus in the studied region under the local conditions of that period. Hemogregarines was detected in blood samples of free-living Brazilian testudines. Gametocytes of hemogregarines were observed in Podocnemis expansa blood smears. Hemogregarines DNA fragments based on the 18S rRNA gene were detected in P. expansa. We propose that P. expansa were parasitized by a new genotype of Haemogregarina. Haemosporidians was not observed in either P. expansa or Phrynops geoffroanus samples.
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Affiliation(s)
- Juliana Paula de Oliveira
- São Paulo State University (Unesp), School of Agricultural and Veterinarian Studies, Jaboticabal Campus, Via de Acesso Professor Paulo Donato Castellane s/n, 14.884-900, Jaboticabal, SP, Brazil
| | - Marcos Rogério André
- São Paulo State University (Unesp), School of Agricultural and Veterinarian Studies, Jaboticabal Campus, Via de Acesso Professor Paulo Donato Castellane s/n, 14.884-900, Jaboticabal, SP, Brazil
| | | | - Ana Paula Gomes Lustosa
- Chico Mendes Institute for Biodiversity Conservation (ICMBio), National Center for Research and Conservation of Reptiles and Amphibians (RAN), Rua 229, n 95, Setor Leste Universitário, 74.605-090, Goiânia, GO, Brazil
| | - Karin Werther
- São Paulo State University (Unesp), School of Agricultural and Veterinarian Studies, Jaboticabal Campus, Via de Acesso Professor Paulo Donato Castellane s/n, 14.884-900, Jaboticabal, SP, Brazil
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Prevalence and genetic diversity of blood parasite mixed infections in Spanish terrapins, Mauremys leprosa. Parasitology 2017. [PMID: 28641604 DOI: 10.1017/s0031182017000889] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Blood parasites such as haemogregarines and haemosporidians have been identified in almost all groups of vertebrates and may cause serious damages to their hosts. However, very little is known about biodiversity of these parasites and their effects on some groups of reptiles such as terrapins. Moreover, the information on virulence from blood parasites mixed infection is largely unknown in reptiles. With this aim, we investigated for the first time the prevalence and genetic diversity of blood parasites from one genus of haemoparasitic aplicomplexan (Hepatozoon) in two populations of Spanish terrapins (Mauremys leprosa), a semi-aquatic turtle from southwestern Europe with a vulnerable conservation status. We also examined the association between mixed blood parasite infection and indicators of health of terrapins (body condition, haematocrit values and immune response). Blood parasite infection with Hepatozoon spp was detected in 46·4% of 140 examined terrapins. The prevalence of blood parasites infection differed between populations. We found two different lineages of blood parasite, which have not been found in previous studies. Of the turtles with infection, 5·7% harboured mixed infection by the two lineages. There was no difference in body condition between uninfected, single-infected and mixed-infected turtles, but mixed-infected individuals had the lowest values of haematocrit, thus revealing the negative effects of blood parasite mixed infections. Immune response varied among terrapins with different infection status, where mixed infected individuals had higher immune response than uninfected or single-infected terrapins.
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Boundenga L, Perkins SL, Ollomo B, Rougeron V, Leroy EM, Renaud F, Prugnolle F. Haemosporidian Parasites of Reptiles and Birds from Gabon, Central Africa. J Parasitol 2017; 103:330-337. [PMID: 28509658 DOI: 10.1645/16-118] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Haemosporidian parasites are protozoans that infect many different vertebrate hosts. Re-examination of the diversity of haemosporidian parasites, using molecular tools, has generally led to rearrangements of traditional classifications. In this study, we explored the diversity of haemosporidian parasites infecting some species of reptile and birds living in the forests of Gabon, Central Africa, by analyzing a collection of 128 samples of reptiles and birds. We found that samples from 2 tortoise species (Pelusios castaneus and Kinixys erosa) and 3 bird species (Turtur afer, Ceratogymna atrata, and Agelastes niger) were infected by Haemocystidium spp. and Parahaemoproteus spp., respectively. From an ecological point of view, these lineages of parasites do not show host specificity because we have found them in several host species (2 tortoise and 3 bird species) that come from different areas of Gabon forest which are infected with these parasites. Also, our phylogenetic analyses revealed that the obtained lineages are related to isolates from other continents found in the same groups of vertebrates. Thus, our results show that haemosporidian parasites are also infecting central African vertebrates and that new lineages of these parasites are circulating in wild animals of the Gabon forest.
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Affiliation(s)
- Larson Boundenga
- Centre International de Recherche de Médicales de Franceville (CIRMF), BP: 769 Franceville, Gabon
| | - Susan L Perkins
- Centre International de Recherche de Médicales de Franceville (CIRMF), BP: 769 Franceville, Gabon
| | - Benjamin Ollomo
- Centre International de Recherche de Médicales de Franceville (CIRMF), BP: 769 Franceville, Gabon
| | - Virginie Rougeron
- Centre International de Recherche de Médicales de Franceville (CIRMF), BP: 769 Franceville, Gabon
| | - Eric M Leroy
- Centre International de Recherche de Médicales de Franceville (CIRMF), BP: 769 Franceville, Gabon
| | - François Renaud
- Centre International de Recherche de Médicales de Franceville (CIRMF), BP: 769 Franceville, Gabon
| | - Franck Prugnolle
- Centre International de Recherche de Médicales de Franceville (CIRMF), BP: 769 Franceville, Gabon
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Reconstruction of the evolutionary history of Haemosporida (Apicomplexa) based on the cyt b gene with characterization of Haemocystidium in geckos (Squamata: Gekkota) from Oman. Parasitol Int 2016; 65:5-11. [DOI: 10.1016/j.parint.2015.09.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Revised: 09/07/2015] [Accepted: 09/10/2015] [Indexed: 01/05/2023]
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Prevalence of Haemoproteus spp. (Apicomplexa: Haemoproteidae) in tortoises in Brazil and its molecular phylogeny. Parasitol Res 2015; 115:249-54. [PMID: 26358101 DOI: 10.1007/s00436-015-4741-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 09/04/2015] [Indexed: 10/23/2022]
Abstract
Captive terrestrial tortoises of the species Chelonoidis carbonaria (n = 17) and Chelonoidis denticulata (n = 37) in the state of Minas Gerais, southeastern Brazil, were examined for hematozoans by using a combination of microscopic and molecular methods. Microscopic examination revealed young intra-erythrocytic forms in blood smears from both species of tortoises. The results of PCR, sequencing, and phylogenetic analysis indicated that these parasites belonged to the Haemoproteus spp., whose observed prevalence was 17.6 % in C. carbonaria and 13.5 % in C. denticulata. Phylogenetic analysis indicated that these sequences formed a clade that was grouped with other sequences of Haemoproteus spp. parasites in birds, separate from the clade formed by Haemoproteus spp. of reptiles. This study expands the information regarding the occurrence and distribution of hemosporidia in turtles and is the first study of blood parasites in C. carbonaria.
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Sallaberry-Pincheira N, Gonzalez-Acuña D, Herrera-Tello Y, Dantas GPM, Luna-Jorquera G, Frere E, Valdés-Velasquez A, Simeone A, Vianna JA. Molecular Epidemiology of Avian Malaria in Wild Breeding Colonies of Humboldt and Magellanic Penguins in South America. ECOHEALTH 2015; 12:267-277. [PMID: 25492695 DOI: 10.1007/s10393-014-0995-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 09/21/2014] [Accepted: 10/25/2014] [Indexed: 06/04/2023]
Abstract
Avian malaria is a disease caused by species of the genera Haemoproteus, Leucocytozoon, and Plasmodium. It affects hundreds of bird species, causing varied clinical signs depending on the susceptibility of the host species. Although high mortality has been reported in captive penguins, limited epidemiological studies have been conducted in wild colonies, and isolated records of avian malaria have been reported mostly from individuals referred to rehabilitation centers. For this epidemiological study, we obtained blood samples from 501 adult Humboldt and 360 adult Magellanic penguins from 13 colonies throughout South America. To identify malaria parasitaemia, we amplified the mtDNA cytochrome b for all three parasite genera. Avian malaria was absent in most of the analyzed colonies, with exception of the Punta San Juan Humboldt penguin colony, in Peru, where we detected at least two new Haemoproteus lineages in three positive samples, resulting in a prevalence of 0.6% for the species. The low prevalence of avian malaria detected in wild penguins could be due to two possible causes: A low incidence, with high morbidity and mortality in wild penguins or alternatively, penguins sampled in the chronic stage of the disease (during which parasitaemia in peripheral blood samples is unlikely) would be detected as false negatives.
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Affiliation(s)
- Nicole Sallaberry-Pincheira
- Laboratorio Fauna Australis, Departamento de Ecosistemas y Medio Ambiente, Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago, Chile
- Escuela Medicina Veterinaria, Facultad Ecología y Recursos Naturales, Universidad Andrés Bello, Santiago, Chile
| | | | - Yertiza Herrera-Tello
- Laboratorio Fauna Australis, Departamento de Ecosistemas y Medio Ambiente, Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago, Chile
| | - Gisele P M Dantas
- Pontificia Universidade Catolica de Minas Gerais, Belo Horizonte, Brazil
| | - Guillermo Luna-Jorquera
- Universidad Católica del Norte, Millenium Nucleus of Ecology and Sustainable Management of Oceanic Islands ESMOI, Centro de Estudios Avanzados en Zonas Áridas CEAZA, Coquimbo, Chile
| | - Esteban Frere
- Centro de Investigaciones de Puerto Deseado, Universidad Nacional de la Patagonia Austral, Puerto Deseado, Argentina
| | - Armando Valdés-Velasquez
- Laboratorio de Estudios en Biodiversidad, Facultad de Ciencias Biológicas y Fisiológicas, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Alejandro Simeone
- Departamento de Ecología y Biodiversidad, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Santiago, Chile
| | - Juliana A Vianna
- Laboratorio Fauna Australis, Departamento de Ecosistemas y Medio Ambiente, Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago, Chile.
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Javanbakht H, Kvičerová J, Dvořáková N, Mikulíček P, Sharifi M, Kautman M, Maršíková A, Široký P. Phylogeny, Diversity, Distribution, and Host Specificity of Haemoproteus spp. (Apicomplexa: Haemosporida: Haemoproteidae) of Palaearctic Tortoises. J Eukaryot Microbiol 2015; 62:670-8. [PMID: 25939459 DOI: 10.1111/jeu.12227] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 01/02/2015] [Accepted: 02/09/2015] [Indexed: 11/29/2022]
Abstract
A complex wide-range study on the haemoproteid parasites of chelonians was carried out for the first time. Altogether, 811 samples from four tortoise species from an extensive area between western Morocco and eastern Afghanistan and between Romania and southern Syria were studied by a combination of microscopic and molecular-genetic methods. Altogether 160 Haemoproteus-positive samples were gathered in the area between central Anatolia and eastern Afghanistan. According to variability in the cytochrome b gene, two monophyletic evolutionary lineages were distinguished; by means of microscopic analysis it was revealed that they corresponded to two previously described species-Haemoproteus anatolicum and Haemoproteus caucasica. Their distribution areas overlap only in a narrow strip along the Zagros Mts. range in Iran. This fact suggests the involvement of two different vector species with separated distribution. Nevertheless, no vectors were confirmed. According to phylogenetic analyses, H. caucasica represented a sister group to H. anatolicum, and both of them were most closely related to H. pacayae and H. peltocephali, described from South American river turtles. Four unique haplotypes were revealed in the population of H. caucasica, compared with seven haplotypes in H. anatolicum. Furthermore, H. caucasica was detected in two tortoise species, Testudo graeca and Testudo horsfieldii, providing evidence that Haemoproteus is not strictly host-specific to the tortoise host species.
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Affiliation(s)
- Hossein Javanbakht
- Department of Biology, Faculty of Science, Razi University, Baghabrisham, 67149, Kermanshah, Iran
| | - Jana Kvičerová
- Biology Centre, Institute of Parasitology, Academy of Sciences of the Czech Republic, Branišovská 31, 370 05, České Budějovice, Czech Republic.,Department of Parasitology, Faculty of Science, University of South Bohemia, Branišovská 31, 370 05, České Budějovice, Czech Republic
| | - Nela Dvořáková
- Department of Biology and Wildlife Diseases, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences Brno, Palackého 1/3, 612 42, Brno, Czech Republic.,CEITEC-Central European Institute of Technology, University of Veterinary and Pharmaceutical Sciences Brno, Palackého 1/3, 612 42, Brno, Czech Republic
| | - Peter Mikulíček
- Department of Zoology, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina B-1, 842 15, Bratislava, Slovak Republic
| | - Mozafar Sharifi
- Department of Biology, Faculty of Science, Razi University, Baghabrisham, 67149, Kermanshah, Iran
| | - Matej Kautman
- Department of Biology and Wildlife Diseases, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences Brno, Palackého 1/3, 612 42, Brno, Czech Republic
| | - Aneta Maršíková
- Biology Centre, Institute of Parasitology, Academy of Sciences of the Czech Republic, Branišovská 31, 370 05, České Budějovice, Czech Republic.,Department of Parasitology, Faculty of Science, University of South Bohemia, Branišovská 31, 370 05, České Budějovice, Czech Republic
| | - Pavel Široký
- Department of Biology and Wildlife Diseases, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences Brno, Palackého 1/3, 612 42, Brno, Czech Republic.,CEITEC-Central European Institute of Technology, University of Veterinary and Pharmaceutical Sciences Brno, Palackého 1/3, 612 42, Brno, Czech Republic
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Fecchio A, Lima M, Silveira P, Ribas A, Caparroz R, Marini M. Age, but not sex and seasonality, influence Haemosporida prevalence in White-banded Tanagers (Neothraupis fasciata) from central Brazil. CAN J ZOOL 2015. [DOI: 10.1139/cjz-2014-0119] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Despite many studies on avian blood parasites, we still have a limited understanding of the mechanisms that drive patterns of haemosporidian infection among tropical birds, including effects associated with sex, age, and seasonality. Using molecular and morphological methods for blood-parasite detection, we found that juvenile White-banded Tanagers (Neothraupis fasciata (Lichtenstein, 1823)) had lower haemosporidian prevalence than adults in a population within central Brazil. However, no sex or seasonal differences were detected. Of the 92 White-banded Tanagers analyzed, 67 individuals (72.8% prevalence) were infected with either Haemoproteus or Plasmodium (phylum Sporozoa, class Coccidea, order Haemosporida). Sequencing of a portion of the mitochondrial cytochrome b gene revealed six haemosporidian lineages: two lineages within the genus Haemoproteus and four within the genus Plasmodium. The prevalences of Plasmodium and Haemoproteus parasites were 43.5% and 17.4%, respectively. Our results suggest that this species maintains chronic infections all year round and individuals are able to sustain high parasite pressure.
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Affiliation(s)
- A. Fecchio
- Laboratório de Evolução e Genética Animal, Departamento de Biologia, Universidade Federal do Amazonas, Avenida Gal. Rodrigo Octávio Jordão Ramos, 3000, Coroado I, Manaus, 69077-000, Brazil
| | - M.R. Lima
- Programa de Pós-Graduação em Ciências Biológicas, Departamento de Biologia Animal e Vegetal, Universidade Estadual de Londrina, 86051-990, Brazil
| | - P. Silveira
- Laboratório de Malária, Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil
| | - A.C.A. Ribas
- Faculdade de Computação, Universidade Federal de Mato Grosso do Sul, Campo Grande, 79070-900, Brazil
| | - R. Caparroz
- Departamento de Genética e Morfologia, Universidade de Brasília, Brasília, 70910-900, Brazil
| | - M.Â. Marini
- Departamento de Zoologia, Universidade de Brasília, Brasília, 70910-900, Brazil
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Perkins SL. Malaria's many mates: past, present, and future of the systematics of the order Haemosporida. J Parasitol 2013; 100:11-25. [PMID: 24059436 DOI: 10.1645/13-362.1] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Malaria has been one of the most important diseases of humans throughout history and continues to be a major public health concern. The 5 species of Plasmodium that cause the disease in humans are part of the order Haemosporida, a diverse group of parasites that all have heteroxenous life cycles, alternating between a vertebrate host and a free-flying, blood-feeding dipteran vector. Traditionally, the identification and taxonomy of these parasites relied heavily on life-history characteristics, basic morphological features, and the host species infected. However, molecular approaches to resolving the phylogeny of the group have sometimes challenged many of these traditional hypotheses. One of the greatest debates has concerned the origin of the most virulent of the human-infecting parasites, Plasmodium falciparum, with early results suggesting a close relationship with an avian parasite. Subsequent phylogenetic studies placed it firmly within the mammalian clade instead, but the avian origin hypothesis has been revived with recent genome-based analyses. The rooting of the tree of Haemosporida has also been inconsistent, and the various topologies that result certainly affect our interpretation of the history of the group. There is clearly a pressing need to obtain a much more complete degree of taxon sampling of haemosporidians, as well as a greater number of characters before confidence can be placed in any hypothesis regarding the evolutionary history of the order. There are numerous challenges moving forward, particularly for generating complete genome sequences of avian and saurian parasites.
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Affiliation(s)
- Susan L Perkins
- Sackler Institute for Comparative Genomics, American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024
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