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Biswas PG, Ohari Y, Mohanta UK, Itagaki T. Molecular characterization of Oxyspirura mansoni and Philophthalmus gralli collected from the eyes of domestic chickens in Bangladesh. Parasitol Int 2020; 80:102243. [PMID: 33186725 DOI: 10.1016/j.parint.2020.102243] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 10/24/2020] [Accepted: 11/06/2020] [Indexed: 11/25/2022]
Abstract
A variety of helminths have been found in domestic chickens in Bangladesh, but little is known about their gene sequences. Here, parasitic nematodes and trematodes were collected from the eyes of domestic chickens and analyzed for their morphological and morphometric characteristics, and characterized molecularly. The helminths were identified as Oxyspirura mansoni and Philophthalmus gralli. The ITS1 and ITS2 sequences of O. mansoni were 532 bp and 306 bp in length, respectively, and showed low identity (50.7-62.7%) with those of O. petrowi and O. conjunctivalis. Furthermore, the O. mansoni CO1 sequences (393 bp) showed five haplotypes (97.5-99.5% similarity) that formed a monophyletic clade. With respect to P. gralli, the ITS1 (452 bp) and ITS2 (736 bp) sequences showed 100% similarity with the reference sequences in GenBank. Both the ND1 and CO1 phylograms showed that P. gralli from Bangladesh, Costa Rica and Peru form a monophyletic clade, distinct from the clades of P. lucipetus and P. lacrymosus. Our data show that, Philophthalmus gralli isolates from Bangladesh, Costa Rica and Peru are genetically close to each other.
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Affiliation(s)
- Peru Gopal Biswas
- Laboratory of Veterinary Parasitology, Faculty of Agriculture, Iwate University, 3-18-8 Ueda, Morioka 020-8550, Japan; Department of Pathogenetic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Yuma Ohari
- National Research Center for Protozoan Diseases, Obihiro University of Agricultural and Veterinary Medicine, Japan
| | - Uday Kumar Mohanta
- Department of Microbiology and Parasitology, Sher-E-Bangla Agricultural University, Dhaka, Bangladesh
| | - Tadashi Itagaki
- Laboratory of Veterinary Parasitology, Faculty of Agriculture, Iwate University, 3-18-8 Ueda, Morioka 020-8550, Japan; Department of Pathogenetic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
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Abstract
Abstract
Thelaziosis is a parasitic disease of the eye that has become more common in Europe over the last twenty years. It is caused by a nematode, order Spirurida, family Thelaziidae. The transmission of this parasite occurs by the dipteran flies. Thelazia callipaeda occurs in the conjunctival sac, under the third eyelid or in the lacrimal ducts, causing blepharospasm, conjunctivitis, keratitis and sometimes corneal ulceration. Thelaziosis is a zoonotic disease. It occurs in humans, domestic animals and wildlife. Between 2016 and 2018 three cases of canine ocular thelaziosis occurred in dogs admitted to the Small Animals Clinic in Kosice, Slovakia. In all cases, the systemic and local treatments were administered. The parasites were removed from the conjunctival sac. The identification of Thelazia callipaeda was performed by microscopic examinations.
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Chowdhury R, Gogoi M, Sarma A, Sharma A. Ocular thelaziasis: A case report from Assam, India. Trop Parasitol 2018; 8:94-97. [PMID: 30693214 PMCID: PMC6329271 DOI: 10.4103/tp.tp_49_17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/13/2018] [Indexed: 11/15/2022] Open
Abstract
We report here a case of human ocular thelaziasis that was discovered accidentally during cataract surgery. A 58-year-old farmer attended an eye camp for diminished vision of the left eye, which was diagnosed later on as cataract. He was referred to a tertiary care hospital in Assam. During the cataract surgery, two small, motile, chalky white, translucent worms were removed from the left fornix. They were identified as female Thelazia callipaeda. Rare occurrence of this disease and its association with both extra and intraocular manifestations leading to ocular morbidity is the rationale for presenting this case.
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Affiliation(s)
- Runumi Chowdhury
- Department of Microbiology, Gauhati Medical College, Guwahati, Assam, India
| | - Mayuri Gogoi
- Department of Microbiology, Gauhati Medical College, Guwahati, Assam, India
| | - Anjan Sarma
- Department of Microbiology, Gauhati Medical College, Guwahati, Assam, India
| | - Ajanta Sharma
- Department of Microbiology, Gauhati Medical College, Guwahati, Assam, India
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Rojas A, Dvir E, Farkas R, Sarma K, Borthakur S, Jabbar A, Markovics A, Otranto D, Baneth G. Phylogenetic analysis of Spirocerca lupi and Spirocerca vulpis reveal high genetic diversity and intra-individual variation. Parasit Vectors 2018; 11:639. [PMID: 30547850 PMCID: PMC6295112 DOI: 10.1186/s13071-018-3202-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 11/19/2018] [Indexed: 12/12/2022] Open
Abstract
Background Spirocerca lupi is a parasitic nematode of canids that can lead to a severe and potentially fatal disease. Recently, a new species, Spirocerca vulpis, was described from red foxes in Europe, suggesting a high genetic diversity of the Spirocerca spp. infecting canids. The genetic variation and phylogenetic relationships of S. lupi collected from naturally-infected domestic dogs from Australia, Hungary, Israel, Italy, India and South Africa, and S. vulpis from red foxes from Bosnia and Herzegovina, Italy and Spain, was studied using mitochondrial and rDNA markers. Results A high intra-individual variation was found in the first internal transcribed spacer (ITS1) locus in all Spirocerca spp., ranging between 0.37–2.84%, with up to six haplotypes per specimen. In addition, a combination of phylogenetic and haplotype analyses revealed a large variability between S. lupi specimens collected from different geographical locations using the ITS1 (0.37–9.33%) and the cytochrome c oxidase subunit 1 (cox1) gene (1.42–6.74%). This genetic diversity led to the identification of two S. lupi genotypes circulating among dogs (PTP support > 0.829), including genotype 1 found in S. lupi from Australia, India, Israel and South Africa, and genotype 2 represented by specimens from Hungary and Italy. These genotypes presented pairwise nucleotide distances of 0.14%, 8.06% and 6.48 ± 0.28% in the small rDNA subunit (18S), ITS1 and cox1 loci, respectively. Additionally, Nei’s genetic distance in the ITS1 showed a further subdivision of genotype 1 worms into 1A (Israel and South Africa) and 1B (Australia and India). A morphological analysis of the anterior and posterior extremities of genotype 1 and genotype 2 worms using scanning electron microscopy did not show any differences between the specimens, contrary to the morphological differences between S. lupi and S. vulpis. Conclusions These findings demonstrate the high genetic variability among Spirocerca spp. from different geographical locations, thereby expanding our understanding of the epidemiology, evolution and phylogenetic variability within the genus. Electronic supplementary material The online version of this article (10.1186/s13071-018-3202-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alicia Rojas
- Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Eran Dvir
- Department of Animal Sciences, Tel-Hai Academic College, Upper Galilee, Israel
| | - Róbert Farkas
- Department of Parasitology and Zoology, University of Veterinary Medicine, Budapest, Hungary
| | - Kalyan Sarma
- Department of Veterinary Medicine, College of Veterinary Sciences and Animal Husbandry, Central Agricultural University, Mizoram, India
| | - Sonjoy Borthakur
- Department of Veterinary Parasitology, College of Veterinary Sciences and Animal Husbandry, Central Agricultural University, Mizoram, India
| | - Abdul Jabbar
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Victoria, Australia
| | | | - Domenico Otranto
- Department of Veterinary Medicine, University of Bari, Valenzano, Italy
| | - Gad Baneth
- Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, Rehovot, Israel.
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5
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Zhang X, Shi YL, Han LL, Xiong C, Yi SQ, Jiang P, Wang ZX, Shen JL, Cui J, Wang ZQ. Population structure analysis of the neglected parasite Thelazia callipaeda revealed high genetic diversity in Eastern Asia isolates. PLoS Negl Trop Dis 2018; 12:e0006165. [PMID: 29324738 PMCID: PMC5783425 DOI: 10.1371/journal.pntd.0006165] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 01/24/2018] [Accepted: 12/13/2017] [Indexed: 01/20/2023] Open
Abstract
Background Thelazia callipaeda is the causative agent of thelaziasis in canids, felids and humans. However, the population genetic structure regarding this parasite remains unclear. Methodology/principal findings In this study, we first explored the genetic variation of 32 T. callipaeda clinical isolates using the following multi-molecular markers: cox1, cytb, 12S rDNA, ITS1 and 18S rDNA. The isolates were collected from 13 patients from 11 geographical locations in China. Next, the population structure of T. callipaeda from Europe and other Asian countries was analyzed using the cox1 sequences collected during this study and from the GenBank database. In general, the Chinese clinical isolates of T. callipaeda expressed high genetic diversity. Based on the cox1 gene, a total of 21 haplotypes were identified. One only circulated in European countries (Hap1), while the other 20 haplotypes were dispersed in Korea, Japan and China. There were five nucleotide positions in the cox1 sequences that were confirmed as invariable among individuals from Europe and Asia, but the sequences were distinct between these two regions. Population differences between Europe and Asian countries were greater than those among China, Korea and Japan. The T. callipaeda populations from Europe and Asia should be divided into two separate sub-populations. These two groups started to diverge during the middle Pleistocene. Neutrality tests, mismatch distribution and Bayesian skyline plot (BSP) analysis all rejected possible population expansion of T. callipaeda. Conclusions The Asian population of T. callipaeda has a high level of genetic diversity, but further studies should be performed to explore the biology, ecology and epidemiology of T. callipaeda. Thelazia callipaeda is the causative agent of thelaziasis canids, felids and humans. Despite the existing threat of thelaziosis in China, the genetic diversity of T. callipaeda has not been investigated across its wide geographical distribution in China, yet such information may provide insight into the disease epidemiology and the development of specific control measures. In this study, the genetic variation of 32 T. callipaeda clinical isolates collected from 13 patients from 11 geographical locations in China were explored using the following multi-molecular markers: cox1, cytb, 12S rDNA, ITS1 and 18S rDNA. In addition, the population structure of T. callipaeda from Europe and other Asian countries was analyzed using the cox1 sequences collected during this study and from the GenBank database. In general, the Chinese clinical isolates of T. callipaeda demonstrated high genetic diversity. Based on the cox1 gene, a total of 21 haplotypes were identified, one circulated in European countries (Hap1), while the other 20 haplotypes were dispersed in Korea, Japan and China. There were five nucleotide positions in the cox1 that were confirmed as invariable among individuals from Europe and Asia, but the sequences were distinct between these two regions. Population differences between Europe and Asian countries were greater than those among China, Korea and Japan, such that the T. callipaeda population from Europe and Asia should be divided into two separate sub-populations. These two groups started to diverge during the middle Pleistocene.
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MESH Headings
- Animals
- China
- Cluster Analysis
- Cytochromes b/genetics
- DNA, Helminth/chemistry
- DNA, Helminth/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- DNA, Ribosomal Spacer/chemistry
- DNA, Ribosomal Spacer/genetics
- Electron Transport Complex IV/genetics
- Europe
- Asia, Eastern
- Genetic Variation
- Haplotypes
- Humans
- Phylogeny
- RNA, Ribosomal/genetics
- RNA, Ribosomal, 18S/genetics
- Sequence Analysis, DNA
- Thelazioidea/classification
- Thelazioidea/genetics
- Thelazioidea/isolation & purification
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Affiliation(s)
- Xi Zhang
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, China
| | - Ya Li Shi
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, China
| | - Lu Lu Han
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, China
| | - Chen Xiong
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, China
| | - Shi Qi Yi
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, China
| | - Peng Jiang
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, China
| | - Zeng Xian Wang
- Department of Microbiology and Parasitology, Anhui Medical University, Anhui, China
| | - Ji Long Shen
- Department of Microbiology and Parasitology, Anhui Medical University, Anhui, China
| | - Jing Cui
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, China
- * E-mail: (ZQW); (JC)
| | - Zhong Quan Wang
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, China
- * E-mail: (ZQW); (JC)
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6
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Zhang X, Shi YL, Wang ZQ, Duan JY, Jiang P, Liu RD, Cui J. Morphological and Mitochondrial Genomic Characterization of Eyeworms ( Thelazia callipaeda) from Clinical Cases in Central China. Front Microbiol 2017; 8:1335. [PMID: 28751889 PMCID: PMC5508006 DOI: 10.3389/fmicb.2017.01335] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 06/30/2017] [Indexed: 11/30/2022] Open
Abstract
Thelazia callipaeda, also called the oriental eyeworm, is the major etiological agent of human thelaziasis. Cases of thelaziasis have increased in recent years in China. Although this species is of medical importance, the genetics and phylogenetic systematics of T. callipaeda are poorly understood. In this study, we first reported three cases of thelaziasis in central China. All clinical isolates were identified as T. callipaeda according to morphological characteristics by light microscopy and scanning electron microscopy. Next, complete mitochondrial (mt) genomes for the three T. callipaeda isolates from different geographical locations were fully characterized using an Illumina sequencing platform. In addition, all available mt genomes of spirurid nematodes in GenBank were included to reconstruct the phylogeny and to explore the evolutionary histories of the isolates. The genome features of the T. callipaeda isolates contained 12 PCGs, 22 transfer RNA genes, two ribosomal RNA genes and a major non-coding region. The mtDNA nucleotide sequences of the T. callipaeda isolates from different hosts and different locations were similar. The nad6 gene showed high sequence variability among all isolates, which is worth considering for future population genetic studies of T. callipaeda. Phylogenetic analyses based on maximum parsimony and Bayesian inference methods revealed close relationships among Thelaziidae, Onchocercidae, Setariidae, Gongylonematidae, Physalopteridae, Dracunculidae, and Philometridae. The monophyly of the T. callipaeda isolates from different hosts and distinct geographical locations was confirmed. The entire mt genomes of T. callipaeda presented in this study will serve as a useful dataset for studying the population genetics and phylogenetic relationships of Thelazia species.
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Affiliation(s)
- Xi Zhang
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou UniversityZhengzhou, China
| | - Ya L Shi
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou UniversityZhengzhou, China
| | - Zhong Q Wang
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou UniversityZhengzhou, China
| | - Jiang Y Duan
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou UniversityZhengzhou, China
| | - Peng Jiang
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou UniversityZhengzhou, China
| | - Ruo D Liu
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou UniversityZhengzhou, China
| | - Jing Cui
- Department of Parasitology, School of Basic Medical Sciences, Zhengzhou UniversityZhengzhou, China
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7
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Sun MM, Liu GH, Ando K, Woo HC, Ma J, Sohn WM, Sugiyama H, Zhu XQ. Complete mitochondrial genomes of Gnathostoma nipponicum and Gnathostoma sp., and their comparison with other Gnathostoma species. INFECTION GENETICS AND EVOLUTION 2016; 48:109-115. [PMID: 28025097 DOI: 10.1016/j.meegid.2016.12.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 12/12/2016] [Accepted: 12/21/2016] [Indexed: 11/17/2022]
Abstract
Gnathostomiasis is a foodborne zoonotic parasitosis caused by Gnathostoma nematodes. It has caused significant public problems worldwide, but its molecular biology is limited. The purpose of this study was to decode the complete mitochondrial (mt) genomes of Gnathostoma nipponicum and Gnathostoma sp., and compare their mt sequences with other Gnathostoma species. The complete mt genome sequences were amplified by long-range PCR and determined by subsequent primer walking. The complete mt genomes of G. nipponicum and Gnathostoma sp. were 14,093bp and 14,391bp, respectively. Both of the two mt genomes contain 12 protein-coding genes (PCGs), 2 ribosomal RNA genes and 22 transfer RNA genes. The gene order and transcription direction are the same as G. spinigerum and G. doloresi. The sequence difference across the entire mt genomes varied from 14.4% to 18.2% between G. nipponicum, Gnathostoma sp., G. spinigerum and G. doloresi of Japan and China isolates. Phylogenetic analyses by Bayesian inference (BI) using concatenated amino acid sequences of 12 PCGs showed that G. nipponicum and Gnathostoma sp. are two distinctive species of Gnathostoma, and G. nipponicum are more closely related to Gnathostoma sp. than to G. spinigerum. The mtDNA datasets provide abundant resources of novel markers, which can be used for the studies of molecular epidemiology and diagnosis of Gnathostoma spp.
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Affiliation(s)
- Miao-Miao Sun
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, PR China; College of Animal Science and Technology, Anhui Agricultural University, Hefei, Anhui Province 230036, PR China
| | - Guo-Hua Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, PR China; College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province 410128, PR China.
| | - Katsuhiko Ando
- Department of Medical Zoology, Mie University School of Medicine, Mie 514-8507, Japan
| | - Ho-Choon Woo
- Department of Veterinary Parasitology, Jeju National University College of Veterinary Medicine, Jeju 690-756, Republic of Korea
| | - Jun Ma
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, PR China
| | - Woon-Mok Sohn
- Department Parasitology and Tropical Medicine, Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 52727, Republic of Korea
| | - Hiromu Sugiyama
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, PR China; College of Animal Science and Technology, Anhui Agricultural University, Hefei, Anhui Province 230036, PR China; College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province 410128, PR China.
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Xiong F, Li WX, Wu SG, Zou H, Wang GT. Molecular Phylogeny and Host Specificity of the LarvalEustrongylides(Nematoda: Dioctophmidae) From Freshwater Fish in China. J Parasitol 2013; 99:137-44. [DOI: 10.1645/ge-3163.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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9
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Liu GH, Gasser RB, Otranto D, Xu MJ, Shen JL, Mohandas N, Zhou DH, Zhu XQ. Mitochondrial genome of the eyeworm, Thelazia callipaeda (Nematoda: Spirurida), as the first representative from the family Thelaziidae. PLoS Negl Trop Dis 2013; 7:e2029. [PMID: 23383353 PMCID: PMC3561134 DOI: 10.1371/journal.pntd.0002029] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 12/07/2012] [Indexed: 12/14/2022] Open
Abstract
Human thelaziosis is an underestimated parasitic disease caused by Thelazia species (Spirurida: Thelaziidae). The oriental eyeworm, Thelazia callipaeda, infects a range of mammalian definitive hosts, including canids, felids and humans. Although this zoonotic parasite is of socio-economic significance in Asian countries, its genetics, epidemiology and biology are poorly understood. Mitochondrial (mt) DNA is known to provide useful genetic markers to underpin fundamental investigations, but no mt genome had been characterized for any members of the family Thelaziidae. In the present study, we sequenced and characterized the mt genome of T. callipaeda. This AT-rich (74.6%) mt genome (13,668 bp) is circular and contains 12 protein-coding genes, 22 transfer RNA genes and two ribosomal RNA genes, but lacks an atp8 gene. All protein-coding genes are transcribed in the same direction; the gene order is the same as those of Dirofilaria immitis and Setaria digitata (Onchocercidae), but distinct from Dracunculus medinensis (Dracunculidae) and Heliconema longissimum (Physalopteridae). Phylogenetic analyses of the concatenated amino acid sequence data for all 12 protein-coding genes by Bayesian inference (BI) showed that T. callipaeda (Thelaziidae) is related to the family Onchocercidae. This is the first mt genome of any member of the family Thelaziidae and should represent a new source of genetic markers for studying the epidemiology, ecology, population genetics and systematics of this parasite of humans and other mammals. Human thelaziosis is an underestimated parasitic disease caused by the eyeworm Thelazia callipaeda (Spirurida: Thelaziidae). Although this parasite is of significance in humans in many Asian countries, its genetics, epidemiology and biology are poorly understood. Mitochondrial (mt) DNA can provide useful genetic markers for fundamental investigations, but no mt genome had been characterized for any members of the family Thelaziidae. In this study, we sequenced and characterized the mt genome of T. callipaeda. This circular mt genome is 13,668 bp long and contains 12 protein-coding genes, 22 transfer RNA genes and two ribosomal RNA genes, but lacks an atp8 gene. Phylogenetic analyses of the concatenated amino acid sequence data for all 12 protein-coding genes by Bayesian inference showed that T. callipaeda is closely related to the family Onchocercidae, consistent with previous study. This is the first mt genome of any member of the family Thelaziidae, and represents a new source of genetic markers for studies of the epidemiology, ecology, population genetics and systematics of this parasite of human and animal health significance.
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Affiliation(s)
- Guo-Hua Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, PR China
- College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province, PR China
| | - Robin B. Gasser
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
- * E-mail: (RBG); (XQZ)
| | - Domenico Otranto
- Dipartimento di Sanità Pubblica e Zootecnia, Università degli Studi di Bari, Valenzano, Bari, Italy
| | - Min-Jun Xu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, PR China
| | - Ji-Long Shen
- Department of Pathogen Biology, Anhui Medical University, Hefei, Anhui Province, China
| | - Namitha Mohandas
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Dong-Hui Zhou
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, PR China
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, PR China
- College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province, PR China
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang Province, PR China
- * E-mail: (RBG); (XQZ)
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10
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Caron Y, Premont J, Losson B, Grauwels M. Thelazia callipaeda
ocular infection in two dogs in Belgium. J Small Anim Pract 2012; 54:205-8. [DOI: 10.1111/jsap.12003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Y. Caron
- Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine; University of Liège; B-4000 Liège Belgium
| | - J. Premont
- Department of Clinical Sciences, Ophthalmology, Faculty of Veterinary Medicine; University of Liège; B-4000 Liège Belgium
| | - B. Losson
- Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine; University of Liège; B-4000 Liège Belgium
| | - M. Grauwels
- Department of Clinical Sciences, Ophthalmology, Faculty of Veterinary Medicine; University of Liège; B-4000 Liège Belgium
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11
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Demeler J, Schein E, von Samson-Himmelstjerna G. Advances in laboratory diagnosis of parasitic infections of sheep. Vet Parasitol 2012; 189:52-64. [DOI: 10.1016/j.vetpar.2012.03.032] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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12
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Testini G, Papini R, Lia R, Parisi A, Dantas-Torres F, Traversa D, Otranto D. New insights into the morphology, molecular characterization and identification of Baylisascaris transfuga (Ascaridida, Ascarididae). Vet Parasitol 2011; 175:97-102. [DOI: 10.1016/j.vetpar.2010.09.017] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Revised: 09/07/2010] [Accepted: 09/15/2010] [Indexed: 11/25/2022]
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13
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Biotechnological advances in the diagnosis of little-known parasitoses of pets. Parasitol Res 2008; 104:209-16. [DOI: 10.1007/s00436-008-1290-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Accepted: 11/13/2008] [Indexed: 11/25/2022]
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Wu SG, Wang GT, Xi BW, Gao D, Nie P. Molecular characteristics of Camallanus Spp. (Spirurida: Camallanidae) in fishes from China based on its rDNA sequences. J Parasitol 2008; 94:731-6. [PMID: 18605775 DOI: 10.1645/ge-1219.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2007] [Accepted: 11/21/2007] [Indexed: 11/10/2022] Open
Abstract
In the paper, we explored the intra- and interspecific evolutionary variation among species of Camallanus collected from different fish species in various regions of China. We determined the internal transcribed spacers of ribosomal DNA (ITS rDNA) sequences of these nematodes. The divergence (uncorrected p-distance) of ITS1, ITS2, and ITS rDNA data sets confirmed 2 valid species of Camallanus in China, i.e., C. cotti and C. hypophthalmichthys. The 2 species were distinguished not only by their different morphologies and host ranges but also by a tetranucleotide microsatellite (TTGC)n present in the ITS1 region of C. cotti. Phylogenetic analyses of the nematodes disclosed 2 main clades, corresponding to different individuals of C. cotti and C. hypophthalmichthys from different fish species in various geographical locations, although the interior nodes of each clade received poor support.
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Affiliation(s)
- Shan Gong Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, and Fish Immunology and Parasitology Group of the Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province, People's Republic of China
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Wu SG, Wang GT, Xi BW, Gao D, Nie P. Molecular Characteristics of Camallanus Spp. (Spirurida: Camallanidae) in Fishes from China Based On its rDNA Sequences. J Parasitol 2008. [DOI: 10.1645/ge-1219r2.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Naem S. Morphological differentiation among three Thelazia species (Nematoda: Thelaziidae) by scanning electron microscopy. Parasitol Res 2007; 101:145-51. [PMID: 17211660 DOI: 10.1007/s00436-006-0432-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2006] [Accepted: 12/06/2006] [Indexed: 10/23/2022]
Abstract
Thelaziasis is an ocular infection of several mammals caused by nematodes of the genus Thelazia (Spirurida, Thelaziidae). The adults live in the lachrymal ducts and conjunctival sacs of infected animals, and transmission occurs by means of different species of muscids. T. rhodesi, T. skrjabini, and T. gulosa affect mainly cattle, inducing conjunctivitis, keratitis, and ocular discharge. This article describes the morphological features of adult T. rhodesi, T. skrjabini, and T. gulosa by scanning electron microscopy and highlights the most relevant differences for their identification.
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Affiliation(s)
- Soraya Naem
- Department of Pathobiology, College of Veterinary Medicine, Urmia University, P.O. Box 1177, Urmia, Iran.
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Developmental Anomalies. JUBB, KENNEDY & PALMER'S PATHOLOGY OF DOMESTIC ANIMALS 2007. [PMCID: PMC7155661 DOI: 10.1016/b978-070202823-6.50055-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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Otranto D, Cantacessi C, Testini G, Lia RP. Phortica variegata as an intermediate host of Thelazia callipaeda under natural conditions: evidence for pathogen transmission by a male arthropod vector. Int J Parasitol 2006; 36:1167-73. [PMID: 16842795 DOI: 10.1016/j.ijpara.2006.06.006] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2006] [Revised: 06/02/2006] [Accepted: 06/08/2006] [Indexed: 10/24/2022]
Abstract
Knowledge about Phortica variegata (Drosophilidae, Steganinae), the intermediate host of the eyeworm Thelazia callipaeda (Spirurida, Thelaziidae), is confined to experimental studies. To investigate the role P. variegata plays in the transmission of T. callipaeda under natural conditions, the population dynamics of these flies in the natural environment and their feeding preferences (on vegetables and/or animal lachrymal secretions) were examined. From April to November 2005, a total number of 969 (557 males and 412 females) P. variegata flies were collected weekly in a region of southern Italy with a history of canine thelaziosis. The flies were identified and dissected or subjected to a PCR assay specific for a region within the ribosomal ITS-1 DNA of T. callipaeda. The zoophilic preferences of P. variegata were assessed by collecting flies around the eyes of a person or around a fruit bait. Seven hundred and twenty flies (398 males and 322 females) were dissected under a stereomicroscope; 249 flies (158 males and 91 females) that died prior to the dissection were subjected to molecular investigation. Only P. variegata males were infected with larval T. callipaeda both at dissection (six, 0.83%) and with the specific PCR (seven, 2.81%), representing a total percentage of 1.34% flies infected. Interestingly, only males were collected around the eyes, compared with a male/female ratio of 1:4 around the fruit. This survey indicated that P. variegata males act as intermediate hosts of T. callipaeda under natural conditions in Europe. Both the zoophilic behaviour of P. variegata males on lachrymal secretions and their role as vector of T. callipaeda have been discussed as they represent a peculiarity in medical and veterinary entomology. The synchrony between the fly population dynamics and the biology of the nematode in the definitive host provides an interesting model for exploring the co-evolution of Thelazia spp. with their hosts.
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Affiliation(s)
- D Otranto
- Department of Animal Health and Welfare, Faculty of Veterinary Medicine, University of Bari, Valenzano, Bari, Italy.
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Abstract
Modern molecular technologies are having a substantial impact in many fundamental and applied areas of parasitology. In particular, polymerase chain reaction (PCR)-coupled approaches have found broad applicability because their sensitivity permits the enzymatic amplification of gene fragments from minute quantities of nucleic acids from tiny amounts of parasite material. Also, high-resolution electrophoretic and genomic methods are finding increased utility. This paper briefly discusses some developments and applications of DNA methods to parasites and highlights their usefulness or potential for those of veterinary importance. Selected examples of applications with implications in fundamental (systematics, population genetics, epidemiology and ecology) and applied (diagnosis, prevention and control) areas are presented. The focus is mainly on tools for the accurate identification of parasitic nematodes and protozoa of socio-economic importance, the diagnosis of infections and the detection of genetic variability using PCR-coupled mutation scanning technology.
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Affiliation(s)
- Robin B Gasser
- Department of Veterinary Science, The University of Melbourne, Werribee, Victoria 3030, Australia.
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Otranto D, Lia RP, Cantacessi C, Testini G, Troccoli A, Shen JL, Wang ZX. Nematode biology and larval development of Thelazia callipaeda (Spirurida, Thelaziidae) in the drosophilid intermediate host in Europe and China. Parasitology 2005; 131:847-55. [PMID: 16336738 DOI: 10.1017/s0031182005008395] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2005] [Revised: 05/12/2005] [Accepted: 05/20/2005] [Indexed: 11/05/2022]
Abstract
Thelazia callipaeda, commonly known as the 'oriental eyeworm', has been recently reported in Italy and other European countries. The insect/s that act as intermediate hosts and details of larval development inside the vector remain unclear. In order to (1) demonstrate the species of fly that may act as vector/s for T. callipaeda in southern Italy (Site A) and China (Site B) and (2) describe the larval development of the nematode in the body of flies, 847 Phortica (Drosophilidae) flies were collected from the above two sites, each with a history of human and/or canine thelaziosis. Flies were identified as Phortica variegata (245 - site A) and Phortica okadai (602 - site B), experimentally infected by 1st-stage larvae (L1), kept at different temperatures and dissected daily until day 180 post-infection (p.i.). Dead flies from site A were subjected to specific polymerase chain reaction (PCR) assay to detect T. callipaeda. To demonstrate the role of Phortica as vectors of T. callipaeda, 3rd-stage larvae (L3) recovered from the proboscis of flies were deposited onto the cornea of the eyes of dogs and rabbits. Following dissection, 3 (2.9%) of P. variegata in site A were found to be infected by L3 in the proboscis on days +14, +21 and +53 p.i., compared with 26 (18.4%) of Phortica flies recorded as being positive by PCR. Sequences from positive PCR products were 99% identical to sequences of the corresponding species available in GenBank (AY207464). At site B, 106 (17.6%) of 602 dissected P. okadai were found to be infected by T. callipaeda larvae (different stages) and in total 62 L3 were recovered from the proboscis of 34 (5.6%) flies. The shortest time in which L3 were found was at day +14, +17, +19, and +50 p.i. respectively, depending on the environmental temperatures. Of 30 flies overwintered for 6 months, 6 L3 were detected at day +180 p.i. in 3 flies (10%). The biology of larval development was reconstructed on the basis of the dissection of 602 P. okadai-infected flies and the morphology of larval stages in the insect body described. The present work provides evidence that P. variegata and P. okadai act as vectors for T. callipaeda in southern Europe and in China, respectively. The phenomenon of overwintering is described here for the first time for T. callipaeda and discussed. Finally, the relationship between T. callipaeda and its fly vector is considered in light of disease prophylaxis and to model its dissemination into habitats and environments favourable to Phortica flies.
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Affiliation(s)
- D Otranto
- Department of Animal Health and Welfare, Faculty of Veterinary Medicine, University of Bari, P.O. Box 7, 70010, Valenzano, Bari, Italy.
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Otranto D, Lia RP, Testini G, Milillo P, Shen JL, Wang ZX. Musca domestica is not a vector of Thelazia callipaeda in experimental or natural conditions. MEDICAL AND VETERINARY ENTOMOLOGY 2005; 19:135-9. [PMID: 15958022 DOI: 10.1111/j.0269-283x.2005.00554.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Thelazia callipaeda Railliet and Henry (Spirurida: Thelaziidae), commonly called oriental eyeworm for its widespread presence in the Far East, has been recently found to affect dogs, cats and foxes in northern and southern Italy. Although the biology of T. callipaeda in the definitive hosts has been recently investigated, many doubts still remain about its biology in insect vectors. It has been suggested that more than one species of Diptera, namely Musca domestica Linnaeus (Diptera: Muscidae) and Amiota okadai Maca (Diptera: Drosophilidae), may be involved in the transmission of T. callipaeda in China. The aim of the work described here was to verify the role of M. domestica as a vector of T. callipaeda both in experimental and natural conditions. A total of 310 m. domestica (Group 1) were put in a cage and allowed to feed for 14 days around the eyes of a dog naturally infected by T. callipaeda. Ten flies were collected daily for 14 days. A total of 149 houseflies (Group 2) were fed with T. callipaeda first stage larvae (L1) and dissected at 1, 2 and 7 days post-infection. From June to August 2003, flies were netted (Group 3) in two different sites every 10 days both from the environment and directly from the periocular region of dogs affected by thelaziosis. Musca flies were examined for eyeworms by dissection and visual inspection of house flies (Groups 1 and 2) and using a molecular approach (Groups 1-3) via a specific amplification of the ribosomal internal transcribed spacer 1 (ITS1) sequence of T. callipaeda. On the whole, 180 pools of M. domestica flies were processed molecularly and all the experimentally infected flies (Groups 1 and 2) were found to be negative both at the visual dissection and at the molecular assay. Similarly, the 234 M. domestica collected from Group 3 were negative for T. callipaeda. The results clearly suggest that M. domestica is unlikely to act as a vector of T. callipaeda in southern Europe, in contrast with a single previous report.
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Affiliation(s)
- D Otranto
- Department of Animal Health and Welfare, Faculty of Veterinary Medicine, University of Bari, Italy.
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Traversa D, Otranto D, Iorio R, Giangaspero A. Molecular characterization of Thelazia lacrymalis (Nematoda, Spirurida) affecting equids: a tool for vector identification. Mol Cell Probes 2005; 19:245-9. [PMID: 16038792 DOI: 10.1016/j.mcp.2005.01.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2004] [Accepted: 01/25/2005] [Indexed: 11/17/2022]
Abstract
Equine thelaziosis caused by the eyeworm Thelazia lacrymalis is a parasitic disease transmitted by muscid flies. Although equine thelaziosis is known to have worldwide distribution, information on the epidemiology and presence of the intermediate hosts of T. lacrymalis is lacking. In the present work, a PCR-RFLP based assay on the first and/or second internal transcribed spacer (ITS1 and ITS2) of ribosomal DNA was developed for the detection of T. lacrymalis DNA in its putative vector(s). The sensitivity of the technique was also assessed. The restriction patterns obtained readily differentiated T. lacrymalis from four species of Musca (Diptera, Muscidae) (i.e. Musca autumnalis, Musca domestica, Musca larvipara and Musca osiris), which are potential vectors of equine eyeworms. The molecular assay presented herein is a useful tool to identify the intermediate host(s) of T. lacrymalis in natural conditions and to study its/their ecology and epidemiology.
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Affiliation(s)
- Donato Traversa
- Department of Biomedical Comparative Sciences, Faculty of Veterinary Medicine, University of Teramo, Piazza Aldo Moro 45, 64100 Teramo, Italy.
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Traversa D, Giangaspero A, Galli P, Paoletti B, Otranto D, Gasser RB. Specific identification of Habronema microstoma and Habronema muscae (Spirurida, Habronematidae) by PCR using markers in ribosomal DNA. Mol Cell Probes 2004; 18:215-21. [PMID: 15271381 DOI: 10.1016/j.mcp.2004.01.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2003] [Accepted: 01/21/2004] [Indexed: 10/26/2022]
Abstract
Gastric or cutaneous habronemosis caused by Habronema microstoma Creplin, 1849 and Habronema muscae Carter, 1865 is a parasitic disease of equids transmitted by muscid flies. There is a paucity of information on the epidemiology of this disease, which is mainly due to limitations with diagnosis in the live animal and with the identification of the parasites in the intermediate hosts. To overcome such limitations, a molecular approach, based on the use of genetic markers in the second internal transcribed spacer (ITS-2) of ribosomal DNA, was established for the two species of Habronema. Characterisation of the ITS-2 revealed sequence lengths and G+C contents of 296 bp and 29.5% for H. microstoma, and of 334 bp and 35.9% for H. muscae, respectively. Exploiting the sequence difference (approximately 40%) between the two species of nematode, primers were designed and tested by the polymerase chain reaction (PCR) for their specificity using a panel of control DNA samples from common equid endoparasites, and from host tissues, faeces or muscid flies. Effective amplification from each of the two species of Habronema was achieved from as little as 10 pg of genomic DNA. Hence, this molecular approach allows the specific identification and differentiation of the DNA from H. microstoma and H. muscae, and could thus provide a molecular tool for the specific detection of Habronema DNA (irrespective of developmental stage) from faeces, skin and muscid fly samples. The establishment of this tool has important implications for the specific diagnosis of clinical cases of gastric and cutaneous habronemosis in equids, and for studying the ecology and epidemiology of the two species of Habronema.
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Affiliation(s)
- Donato Traversa
- Department of Biomedical Comparative Sciences, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy
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Otranto D, Ferroglio E, Lia RP, Traversa D, Rossi L. Current status and epidemiological observation of Thelazia callipaeda (Spirurida, Thelaziidae) in dogs, cats and foxes in Italy: a “coincidence” or a parasitic disease of the Old Continent? Vet Parasitol 2003; 116:315-25. [PMID: 14580802 DOI: 10.1016/j.vetpar.2003.07.022] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Thelazia callipaeda is a spirurid nematode which causes ocular infections in dogs and man and, occasionally, in cats, foxes and rabbits. The intermediate host and vector of T. callipaeda is unknown. For a long time T. callipaeda incidence was reported only from the Russian Federation and the Far East, but recently it has also been found in Italy. In order to investigate the spread of T. callipaeda in Italy, a survey was carried out in two sites, site A in the Piedmont region (North West Italy), and site B in the Basilicata region (Southern Italy). Dogs, cats and foxes in site A and dogs in site B were examined for eyeworms, using different procedures and timing. From January 1995 to August 2002, 91 dogs, 4 cats and 903 fox carcasses were examined in site A, and from October 1999 to January 2003, 443 dogs were examined in site B, and the eyeworms collected were identified using morphological keys. Twenty-one (23.07%) and 185 (41.76%) of the dogs from sites A and B, respectively, were found to be infected by eyeworms; furthermore, all the cats examined and 46 fox carcasses (5.1%) were positive for eyeworms. All the nematodes collected were identified as T. callipaeda. These results indicate that T. callipaeda is not confined to Eastern Europe and Asia, but that it has spread to the Old Continent, and to both Northern and Southern Italy. Considering the high prevalence of infected dogs reported in some municipalities (e.g. 60.14% of 138 dogs examined in a municipality from site B), it is assumed that one or more vectors are significantly present in the areas under investigation. Furthermore, there is good reason to believe that T. callipaeda is also present in other European countries. Speculation as to the origins of this parasitic infestation in Europe and the biology of T. callipaeda and its vector/s is also discussed.
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Affiliation(s)
- Domenico Otranto
- Department of Animal Health and Welfare, Faculty of Veterinary Medicine, University of Bari, Str. Prov. per Casamassima km3, 70010, Bari, Italy.
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