{"content"=>" (Decapoda: Pseudothelphusidae): A New Crab Intermediate Host of in Manabí Province, Ecuador.", "i"=>[{"content"=>"Hypolobocera guayaquilensis"}, {"content"=>"Paragonimus mexicanus"}]} (original) (raw)
Related papers
Detection of Paragonimus mexicanus (Trematoda) metacercariae in crabs from Oaxaca, Mexico
Metacercariae of Paragonimus mexicanus were collected in crabs Tehuana guerreroensis (Rathbun, 1933) in the municipality of Putla, Oaxaca, Mexico. Metacercariae were found in 20.8% of the crabs collected, with an average of 1.9 metacercarie per crab. Stained metacercariae showed the specific characteristics of P. mexicanus by morphology and sequencing a fragment of the 28S ribosomal gene obtained by PCR. These findings reveal that T. guerreroensis is an intermediate host for P. mexicanus; this new report is relevant considering the potential risk of transmission in the states of Oaxaca and Guerrero, Mexico.
Presence of Paragonimus species within secondary crustacean hosts in Bogotá, Colombia
Revista Colombiana de Ciencias Pecuarias, 2019
Background: Paragonimus spp. are trematode parasites that infect human populations worldwide. It is believed that infection rates within Asia reach five to ten percent of the total population. Three of the largest areas of possible infection are Asia, Central and South America as well as Africa, where the total population at risk is estimated to be 293 million people. Humans are infected via ingestion of raw or undercooked decapod crustaceans. Objective: To identify the presence of Paragonimus spp. in crabs from Bogotá, Colombia. Methods: The native crab Neostrengeria macropa and the aquatic invasive crayfish Procambarus clarkii in Bogotá, Colombia, were collected from local markets, pet stores and waterways and dissected to assess the presence of Paragonimus spp. Results: The native crab species, N. macropa (n=29) had an infection prevalence of 17.2%, while the invasive crayfish species, P. clarkii (n=22), had a prevalence of 36.4% combined from both field captured animals and pur...
Parasitology Research, 2007
In several mountainous regions of Northeastern India, foci of Paragonimus infection reportedly involving species that are known to prevail in China have been identified. The present study was undertaken to demonstrate the surface fine topography and sequence analysis of the ribosomal deoxyribonucleic acid (rDNA; second internal transcribed spacer, ITS2) of the metacercarial stages of the lung fluke collected from a mountain stream of the area (Miao, Changlang District in Arunachal Pradesh). The encysted metacercariae were oval in shape and had a smooth surface. The newly excysted metacercaria had a ventral sucker larger than the oral; the body surface was covered with numerous single-pointed and thorn-like tegumentary spines, of which those on the anterior part of the body were bigger in size and showed a gradual reduction in length and number towards the posterior end; dome-shaped papillae in variable numbers were seen around the rim of the oral sucker and were sparsely distributed all over the body surface. The polymerase chain reaction-amplified rDNA ITS2 sequences of the metacercariae were aligned with known sequences for the various species of Paragonimus, and the expectation value was found to be most significant with P. westermani, revealing an absolute match. The surface topography including the number and distribution of papillae and spination patterns and the ITS2 sequences of the metacercariae strongly suggest that the Paragonimus species, prevalent in the region of India, is in fact P. westermani. P. pulmonalis (Baelz 1880 P. ohirai Miyazaki 1939; P. iloktsunensis Chen 1940; P. skrjabini Chen 1959; P. miyazaki Kamo et al. 1961 and P. heterotremus Chen and Hsia 1964, all reported to be occurring in Asia, P. africanus and P. uterobilateralis Voelker and Vogel 1965 in Africa and P. mexicanus Miyazaki and Ishii 1968 in America are considered pathogenic to man. While P. westermani is distributed mostly in Asia, P. heterotremus is the predominant causative agent of paragonimiasis in Thailand (Blair et al. 1999a, b).
Parasitology International, 2017
The trematode Paragonimus mexicanus is the etiological agent of paragonimiasis, a food-borne zoonotic disease in Latin America. This species, as well as Paragonimus caliensis, have been reported from Costa Rica, but it is not known if the two are synonymous. Two types of Paragonimus metacercariae from freshwater pseudothelphusid crabs from several localities in Costa Rica were recognized by light microscopy. Morphologically, these corresponded to descriptions of P. mexicanus and P. caliensis. Metacercariae of the former species lacked a membrane or cyst and their bodies were yellow in color. Those of P. caliensis were contained in a transparent thin cyst and were pink in color. Morphotypes of metacercariae were determined using scanning electron microscopy (SEM). Based on the number and distribution of papillae in the ventral sucker, three morphotypes were found for P. mexicanus and two for P. caliensis. Analysis of DNA sequences (nuclear ribosomal 28S and ITS2 genes, and partial mitochondrial cox1 gene) confirmed the presence of P. mexicanus and provided the first molecular data for P. caliensis. The two species are phylogenetically distinct from each other and distant from the Asian species. The confirmation of P. caliensis as a separate species from P. mexicanus raises several questions about the ecology, biological diversity, and epidemiology of the genus Paragonimus in Costa Rica.
Paragonimus ohirai Metacercariae in Crabs Collected along the Arakawa River in Tokyo, Japan
Journal of Veterinary Medical Science, 2004
Brackish water crabs infected with Paragonimus ohirai metacercariae have been reported in various regions in Japan. However, infected crabs have not been identified in Tokyo. We therefore collected the crab, Chiromantes dehaani, between August 2002 and July 2003 from 12 locations along the Arakawa River that flows through Tokyo. Of the 922 captured crabs, 177 (19%) from 6 l ocations were infected with Paragonimus metacercariae. The prevalence of metacercariae at these 6 locations ranged from 5 to 89%. The number of metacercariae per infected crab ranged from 1 to 190, with an average of 13.1. The morphological features of the metacercariae and of adult worms recovered from test rats infected with metacercariae showed that the metacercariae in the infected crabs were P. ohirai Miyazaki, 1939. The ITS2 sequence data support this conclusion. This paper is the first description of P. ohirai infection of crabs in Tokyo.
Paragonimus metacercariae P. harinasutai/P. bangkokensis Central Viet Nam During our epidemiological surveys for Paragonimus species in central Viet Nam, we found four morphologically different Paragonimus metacercariae in mountainous crabs. They were identified as metacercariae of Paragonimus westermani, P. bangkokensis, P. proliferus, and P. harinasutai in the order of their prevalence in crab hosts. This is the first discovery of P. harinasutai in Viet Nam, co-inhabiting with P. bangkokensis and other species. Metacercariae of P. harinasutai were given orally to a cat to obtain adult worms. Then, ITS2 and CO1 sequences of metacercariae and adults of P. harinasutai, and metacercariae of P. bangkokensis collected from the same place were determined for analyses of phylogenetic relationships to other P. harinasutai and P. bangkokensis populations as well as related species. The results of molecular analyses showed that P. harinasutai from Quang Binh province of central Viet Nam was almost completely identical with those from Vientiane, Lao PDR; P. bangkokensis from Quang Binh, Viet Nam was also almost completely identical with those from Lao PDR and from Quang Ninh province, Viet Nam. Except for one P. harinasutai isolate from China, all populations of P. harinasutai and P. bangkokensis from Thailand, Lao and Viet Nam make a single clade in both ITS2 and CO1 trees. In ITS2 sequences, AT deletion and ATC insertion were observed in some isolates of both species, indicating recent gene flow between P. harinasutai and P. bangkokensis. Moreover, because of their extremely high genetic similarities and their co-inhabitation in the same crab hosts found in Thailand, Lao PDR and Viet Nam, they should be considered as the sister species at the early stage of divergence. In addition, P. microrchis previously described from Yunnan, China should be placed as the synonym of P. harinasutai, because of their morphological and molecular similarities.
Annals of Tropical Medicine & Parasitology, 1990
An explanation was sought for the high prevalence of paragonimiasis in children in Liberia by examining possible modes ofhuman infection from freshwater crabs. The occurrence, frequency of infection, and distribution of metacercariae of Paragonimus uterobilateralis in the freshwater crab Liberonautes latidactylus were studied. The muscles of the cephalothorax and of the legs were found to be the most frequently and most heavily infected parts of the crab. A likely risk of infection of children was considered to be the habit of chewing on, or ingesting in a raw state, the walking legs of infected crabs. Possible contamination of the hands of cooks with metacercariae from the internal organs or haemolymph of infected crabs was thought to be a minor route of infection.
Current status of Paragonimus and paragonimiasis in Ecuador
Memorias do Instituto Oswaldo Cruz, 2014
A review of national and international publications on paragonimiasis in Ecuador, epidemiological records from the Ministry of Public Health and unpublished research data was conducted to summarise the current status of the parasite/disease. The purpose of the review is to educate physicians, policy-makers and health providers on the status of the disease and to stimulate scientific investigators to conduct further research. Paragonimiasis was first diagnosed in Ecuador 94 years ago and it is endemic to both tropical and subtropical regions in 19 of 24 provinces in the Pacific Coast and Amazon regions. Paragonimus mexicanus is the only known species in the country, with the mollusc Aroapyrgus colombiensis and the crabs Moreirocarcinus emarginatus, Hypolobocera chilensis and Hypolobocera aequatorialis being the primary and secondary intermediate hosts, respectively. Recent studies found P. mexicanus metacercariae in Trichodactylus faxoni crabs of the northern Amazon. Chronic pulmonar...
Parasites and epibionts of grapsid crabs in Bahía Blanca estuary, Argentina
Crustaceana, 2011
Epibionts and parasites were recovered from the grapsid crabs Cyrtograpsus angulatus and Neohelice granulata in the Bahía Blanca estuary, Argentina. Among epibionts, we identified a filamentous bacterium, the protozoan Epistylis sp., and the copepod Neocancrincola platensis on the gills; and the barnacles Balanus amphitrite and Balanus glandula as well as the bryozoan Conopeum reticulum on the caparace. Among endoparasites, we identified the acanthocephalan Profilicollis chasmagnathi in the hindgut, nematodes of the subfamily Acuariinae and Ascarophis sp. in the haemocoel, and an encysted cyclophyllidean cestode in the gut wall. Among microphallid digeneans, we found four metacercariae: Maritrema bonaerensis in the gills, muscle, haemocoel, and gonads, Maritrema orensensis in the gills, Levinseniella cruzi in the gonads, and Odhneria sp. in the muscle. Except for P. chasmagnathi, N. platensis, and M. bonaerensis, all other epibionts and digeneans represent new host records. This paper also presents novel information regarding the possible sites of infection for M. bonaerensis. Our results add relevant data about possible life cycles of helminths in the study area.
Journal of Parasitic Diseases, 2021
Paragonimiasis, the disease caused by Paragonimus westermani, is transmitted primarily by freshwater crabs Sundathelphusa philippina in the Philippines. Human infection has been recorded, but there is a dearth of published information on the extent of infection in animal reservoirs, particularly in crabs and snails. This study aimed to investigate the infection status and risk factors of P. westermani in freshwater crabs and melaniid snails collected in an endemic village along Cadacan River in Irosin, Sorsogon, where human cases of paragonimiasis were previously reported. A total of 246 freshwater crabs (118 females, 128 males) were dissected, and the gills, muscles, gonads, and viscera were examined for the presence of metacercariae; of which, 41.87% were found infected. The metacercariae were recovered from the gills (100%) and muscle tissues (7.3%) of infected crabs. Male crabs were more likely to be infected (49.22%) than female crabs (33.90%) (p \ 0.05). Moreover, 70.87% of crabs showed low parasite intensity levels at B 30 metacercariae/g tissue. A negative weak correlation was observed between parasite intensity and crab weight and carapace length, i.e., highly infected crabs were found to be smaller in size. Meanwhile, only 12% of the 150 melaniid snails collected were positive with cercariae with Tarebia granifera and Jagora asperata as the most infected species. Household survey conducted revealed that some knowledge, attitudes, and practices of the locals contribute to the sustained transmission of the parasite in this endemic area. These findings revealed that P. westermani is still prevalent among intermediate hosts and that some social and environmental factors contributed to the sustained parasite transmission in this endemic community.