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1.
J Helminthol ; 97: e23, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36799116

RESUMEN

Various dung beetle species of the family Scarabaeidae have been reported as intermediate hosts of Spirocerca lupi from different geographical locations, but there has been no data from south-east Asian countries. In the present study in Vietnam, by using morphological and molecular approaches, we identified the third-stage larvae of S. lupi for the first time in two dung beetle species, Catharsius molossus and Copris szechouanicus, adding them as new intermediate hosts of this nematode. In addition, both beetle species were infected with larvae of another spirurid nematode of Physocephalus sp. At large magnifications above 200×, these two spirurid larvae can be differentiated from each other by their body size (1880-2662 vs. 1417-1635 µm) and detailed morphological features of the anterior and posterior ends, such as the length of the buccal cavity, the position of the nerve ring and excretory pore, and tail characters. However, it is difficult to distinguish them at a lower magnification due to their minute size. Moreover, morphometric data of S. lupi larvae vary among reports and the body length may overlap with that of Physocephalus sp., thus, misidentification may occur, indicating the necessity of careful examination for accurate identification. The findings of the present study also supposed that larvae of S. lupi and more spirurid nematodes may be concurrently found in various dung beetle species, including C. molossus and C. szechouanicus, in other south-east Asian countries. Thus, more investigations in various countries should be conducted to identify spirurid larvae from dung beetles in order to fully understand their role as intermediate hosts of S. lupi and other spirurid nematodes.


Asunto(s)
Escarabajos , Infecciones por Spirurida , Spiruroidea , Thelazioidea , Animales , Larva , Infecciones por Spirurida/veterinaria , Heces
2.
J Helminthol ; 90(6): 658-662, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26388560

RESUMEN

Conventional identification of Paragonimus species and their natural definitive hosts is based on the morphological features of adult parasites isolated from the lungs of wild mammalian hosts. However, wild animals are protected by strict regulations and sampling is not always possible. Recently, molecular techniques have been developed to identify the internal transcribed spacer (ITS) sequences of Paragonimus eggs in faeces/sputum of human patients. Also, mammalian hosts can be identified using the D-loop sequence of mitochondrial DNA in faecal samples. In this study, we used molecular techniques on faeces from wild animals collected in Da Krong Nature Reserve, Quang Tri province, central Vietnam, where Paragonimus metacercariae are highly prevalent in mountain crabs, to identify Paragonimus species and their natural definitive hosts. The results indicated that wild cats, Prionailurus bengalensis, were infected with at least three different Paragonimus species, P. westermani, P. skrjabini and P. heterotremus. Because all of these species can infect humans in Asian countries, human paragonimiasis should be considered in this area.


Asunto(s)
Enfermedades de los Gatos/diagnóstico , Heces/parasitología , Felidae/parasitología , Técnicas de Diagnóstico Molecular/métodos , Paragonimiasis/veterinaria , Paragonimus/aislamiento & purificación , Animales , Enfermedades de los Gatos/epidemiología , Enfermedades de los Gatos/parasitología , Gatos , ADN de Helmintos/química , ADN de Helmintos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Variación Genética , Genotipo , Paragonimiasis/diagnóstico , Paragonimiasis/epidemiología , Paragonimiasis/parasitología , Paragonimus/clasificación , Paragonimus/genética , Vietnam/epidemiología
3.
J Helminthol ; 89(2): 182-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24229574

RESUMEN

Paragonimus heterotremus, which is an important pathogen for human paragonimiasis in Asia, is recognized as having the smallest metacercariae (maximum diameter < 300 µm) of any previously reported Paragonimus species. Recently, P. pseudoheterotremus has been described from Thailand as a new species having metacercariae (about 200 µm) slightly smaller than those of Thai P. heterotremus. In fact, the small size of P. pseudoheterotremus metacercariae is compatible with those of P. heterotremus from India and China. In this study in Vietnam, we found variably sized small metacercariae which are expected to consist of both P. heterotremus and P. pseudoheterotremus. Contrary to expectation, the adult flukes obtained by separate infection of experimental cats with different sized metacercariae were all identified as P. heterotremus, using both morphological and molecular characteristics. The molecular analyses of an extensive collection of P. heterotremus/P. pseudoheterotremus isolates from Asian countries also indicated that genetic distances between different populations of P. heterotremus are even larger than that between P. pseudoheterotremus and P. heterotremus. The haplotype network showed that all P. heterotremus and P. pseudoheterotremus isolates formed a P. heterotremus complex consisting of three groups with strong geographical origins. In addition, the Indian P. heterotremus group is the root of the other P. heterotremus and P. pseudoheterotremus populations. Based on the observed metacercarial polymorphisms and genetic variation in P. heterotremus, P. pseudoheterotremus should be considered a geographically isolated population of the P. heterotremus complex.


Asunto(s)
Braquiuros/parasitología , Variación Genética , Paragonimiasis/parasitología , Paragonimus/clasificación , Paragonimus/genética , Animales , Gatos , China , Femenino , Humanos , India , Masculino , Datos de Secuencia Molecular , Paragonimus/crecimiento & desarrollo , Paragonimus/aislamiento & purificación , Filogenia , Tailandia , Vietnam
4.
J Helminthol ; 87(2): 141-6, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22354973

RESUMEN

Among about 50 nominal Paragonimus species, Paragonimus proliferus is rather a rare species, found only in Yunnan province, China, until our recent discovery of this species in Lai Chau province, northern Vietnam close to Yunnan, China. Here we add Quang Binh province, central Vietnam as a new endemic area of P. proliferus. Large excysted metacercariae found in mountainous crabs, Potamiscus tannanti, were morphologically identified as P. proliferus, which was confirmed further by molecular analyses. Second internal transcribed spacer (ITS2) sequences of the P. proliferus population in Quang Binh province were completely (100%) identical with those of P. proliferus populations in Lai Chau province, northern Vietnam and Yunnan province, China. However, cytochrome oxidase subunit 1 (CO1) gene sequences of Quang Binh population were significantly different (5.6%) from that of previously reported northern Vietnam and Yunnan, China populations. A phylogenetic tree revealed that all CO1 sequences of P. proliferus Quang Binh population formed a distinct group, which was clustered with northern Vietnam and Yunnan, China populations with the bootstrap value of 75%. This is the first record of the genetically variant population of P. proliferus, distribution of which is geographically remote from the previously reported endemic areas in the border between northern Vietnam and Yunnan, China, suggesting that P. proliferus may be much more widely distributed in the Indochina peninsula (or South-East Asia) than expected.


Asunto(s)
Braquiuros/parasitología , Variación Genética , Paragonimus/clasificación , Paragonimus/genética , Animales , Análisis por Conglomerados , ADN de Helmintos/química , ADN de Helmintos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Complejo IV de Transporte de Electrones/genética , Datos de Secuencia Molecular , Paragonimus/aislamiento & purificación , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Vietnam
5.
J Helminthol ; 87(4): 450-6, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23067567

RESUMEN

Two members of the Paragonimus skrjabini complex, P. skrjabini and P. miyazakii, are now considered as two sub-species, P. skrjabini skrjabini and P. skrjabini miyazakii. They are well known as important pathogens for human paragonimiasis in China and Japan. Recently, members of this species complex have been reported from India. Here we report the first discovery of P. skrjabini from freshwater crab hosts in Thanh Hoa province, Vietnam. For morphological and molecular phylogenetic studies, adult worms were obtained by experimental infection in cats and dogs. Molecular analyses of metacercariae and adults revealed that the P. skrjabini population from Thanh Hoa, Vietnam was almost completely identical with that from Yunnan province, China. Those populations from Thanh Hoa, Vietnam and Yunnan, China and those from Manipur, India were significantly different from P. skrjabini populations reported from other localities of China in cytochrome oxidase subunit 1 (CO1) gene sequences, indicating considerable genetic variation within the P. skrjabini complex. Moreover, low bootstrap values in the CO1 tree suggested that more variant genotypes belonging to P. skrjabini complex may be found in other Asian countries in between Vietnam and India, such as Myanmar, Laos and Thailand. Since P. skrjabini is known as a pathogen for humans, paragonimiasis cases caused by P. skrjabini might be found in Vietnam and other Asian countries.


Asunto(s)
Braquiuros/parasitología , Paragonimus/clasificación , Paragonimus/aislamiento & purificación , Animales , Análisis por Conglomerados , ADN de Helmintos/química , ADN de Helmintos/genética , Complejo IV de Transporte de Electrones/genética , Datos de Secuencia Molecular , Paragonimus/genética , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia , Vietnam
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