RESUMO
BACKGROUND: Paragonimiasis, primarily caused by Paragonimus westermani and P. skrjabini in China, is a common food-borne parasitic zoonosis. However, the national distribution of Paragonimus spp. infection and its associated environmental determinants remain poorly understood. In this paper, we summarize the infection of P. westermani and P. skrjabini and describe key biogeographical characteristics of the endemic areas in China. METHODS: Data on Paragonimus infection in humans and animal hosts were extracted from eight electronic databases, including CNKI, CWFD, Chongqing VIP, SinoMed, Medline, Embase, PubMed, and Web of Science. A random-effects meta-analysis model was used to estimate the pooled prevalence. All survey locations were georeferenced and plotted on China map, and scatter plots were used to illustrate the biogeographical characteristics of regions reporting Paragonimus infection. RESULTS: A total of 28,948 cases of human paragonimiasis have been documented, with 2,401 cases reported after 2010. Among the 11,443 cases with reported ages, 88.05% were children or adolescents. The pooled prevalence of P. skrjabini is 0.45% (95% CI: 0.27-0.66%) in snails, 31.10% (95% CI: 24.77-37.80%) in the second intermediate host, and 20.31% (95% CI: 9.69-33.38%) in animal reservoirs. For P. westermani, the pooled prevalence is 0.06% (95% CI: 0.01-0.13%) in snails, 52.07% (95% CI: 43.56-60.52%) in the second intermediate host, and 21.40% (95% CI: 7.82-38.99%) in animal reservoirs. Paragonimus are primarily distributed in regions with low altitude, high temperature, and high precipitation. In northeastern China, only P. westermani infections have been documented, while in more southern areas, infections of both P. westermani and P. skrjabini have been reported. CONCLUSIONS: Paragonimiasis remains prevalent in China, particularly among children and adolescents. Variations exist in the intermediate hosts and geographical distribution of P. westermani and P. skrjabini. Additionally, altitude, temperature, and precipitation may influence the distribution of Paragonimus.
Assuntos
Paragonimíase , Paragonimus , Animais , Paragonimíase/epidemiologia , Paragonimíase/parasitologia , Humanos , China/epidemiologia , Paragonimus/isolamento & purificação , Paragonimus/classificação , Paragonimus/genética , Zoonoses/parasitologia , Zoonoses/epidemiologia , Prevalência , CriançaRESUMO
As a result of the experimental infection of rats with metacercariae of Paragonimus heterotremus Chen et Hsia, 1964 from crabs (Potamiscus tannanti) caught in Yen Bai province, Vietnam, it was found that worms migrated into the lungs, to the liver and less frequently to the tissue that lines body cavities of the hosts, where they reached the adult stage, but in the muscles, worms stayed at the larval stage. Studies have shown that for P. heterotremus, rats can simultaneously play the role of the final and paratenic host; herewith, an infection with the trematode of this species can lead to the development of three forms of paragonimiasis: pulmonary, hepatic and muscular. Eggs from the adult worms localised in the liver, unlike eggs from the adult worms localised in the lungs, were not excreted into the external environment, but accumulated inside the organ. Histology and description of changes, which take place on the external surface of organs affected with P. heterotremus, are given in this study. Based on the behavioural characteristics of worms during rat infection and molecular genetic data, we established that worms from Vietnam and India should be assigned to different species of Paragonimus. P. heterotremus distribution is limited to the territory of the Southeast China, Northern Vietnam, Laos and Thailand.
Assuntos
Fígado/parasitologia , Pulmão/parasitologia , Músculos/parasitologia , Paragonimíase/patologia , Paragonimus/classificação , Animais , Braquiúros/parasitologia , China , Índia , Laos , Metacercárias/patogenicidade , Paragonimus/genética , Paragonimus/patogenicidade , Ratos , Tailândia , VietnãRESUMO
BACKGROUND: Paragonimus spp. (lung flukes) are among the most injurious foodborne helminths, infecting â¼23 million people and subjecting â¼292 million to infection risk. Paragonimiasis is acquired from infected undercooked crustaceans and primarily affects the lungs but often causes lesions elsewhere including the brain. The disease is easily mistaken for tuberculosis owing to similar pulmonary symptoms, and accordingly, diagnostics are in demand. RESULTS: We assembled, annotated, and compared draft genomes of 4 prevalent and distinct Paragonimus species: Paragonimus miyazakii, Paragonimus westermani, Paragonimus kellicotti, and Paragonimus heterotremus. Genomes ranged from 697 to 923 Mb, included 12,072-12,853 genes, and were 71.6-90.1% complete according to BUSCO. Orthologous group analysis spanning 21 species (lung, liver, and blood flukes, additional platyhelminths, and hosts) provided insights into lung fluke biology. We identified 256 lung fluke-specific and conserved orthologous groups with consistent transcriptional adult-stage Paragonimus expression profiles and enriched for iron acquisition, immune modulation, and other parasite functions. Previously identified Paragonimus diagnostic antigens were matched to genes, providing an opportunity to optimize and ensure pan-Paragonimus reactivity for diagnostic assays. CONCLUSIONS: This report provides advances in molecular understanding of Paragonimus and underpins future studies into the biology, evolution, and pathogenesis of Paragonimus and related foodborne flukes. We anticipate that these novel genomic and transcriptomic resources will be invaluable for future lung fluke research.
Assuntos
Biologia Computacional , Perfilação da Expressão Gênica , Genômica , Paragonimíase/parasitologia , Paragonimus/genética , Transcriptoma , Animais , Biologia Computacional/métodos , Suscetibilidade a Doenças , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Genômica/métodos , Interações Hospedeiro-Parasita , Humanos , Anotação de Sequência Molecular , Família Multigênica , Paragonimus/classificação , FilogeniaRESUMO
Microcercous cercariae possess a very short tail and are produced by digenean species of several families including medically important species, such as members of the genera Paragonimus Braun, 1899, Nanophyetus Chapin, 1927 and Troglotrema Odhner, 1914. During our survey of cercariae of Paragonimus spp. in Vietnam, we found microcercous cercariae from ten (0.29%) out of 3,400 snails of Triculinae gen. sp. 2. They were morphologically and molecularly analysed for species identification. The molecular analysis, based on ITS2 sequences, revealed two distinct species: four specimens were identical to Paragonimus proliferus Hsia et Chen, 1964 (Paragonimidae Dollfus, 1939), and the other six specimens were closest to members of the family Troglotrematidae Odhner, 1914 and were temporarily named Troglotrematidae gen. sp. Morphologically, cercariae of the two species found in this study are similar to each other in their gross characteristics but can be distinguished from one another by subtle morphological details. The cercaria of P. proliferus has an I-shaped excretory bladder and does not have mucous gland cells. In contrast, that of Troglotrematidae gen. sp. has a Y-shaped excretory bladder and mucous gland cells. Besides, the redia of P. proliferus is elongate with a short intestine and contains 5-6 cercariae whereas that of Troglotrematidae gen. sp. is more round with a longer intestine and harbours 3-4 cercariae. Our results have shown the importance of the shape of the excretory bladder and the presence/absence of mucous gland cells of the cercaria as well as the shape and size of the redia, and its intestinal length as valuable taxonomic characters of intramolluscan trematode larvae. In addition, the finding of similar microcercous cercariae of different species in the same snail species suggests that careful attention to morphological details is required in the differentiation of Paragonimus cercariae and those of closely related species.
Assuntos
Paragonimus/isolamento & purificação , Caramujos/parasitologia , Troglotrematidae/isolamento & purificação , Animais , Cercárias/classificação , Cercárias/genética , Cercárias/crescimento & desenvolvimento , Cercárias/isolamento & purificação , DNA de Helmintos/análise , DNA Espaçador Ribossômico/análise , Paragonimus/classificação , Paragonimus/crescimento & desenvolvimento , Filogenia , Análise de Sequência de RNA , Troglotrematidae/classificação , Troglotrematidae/genética , Troglotrematidae/crescimento & desenvolvimento , VietnãRESUMO
BACKGROUND AND OBJECTIVES: Paragonimiasis is endemic in Eastern Nigeria. An upsurge was recorded after the Nigeria/Biafra war as protein lack in Biafra forced people to eat fresh water crabs. Its protean manifestations create confusion with several diseases. Elimination was assumed after a while and suspicion index fell. The interest in reporting this case follows its presentation outside the traditional endemic zone. RESULTS: The patient, though living in Eastern Nigeria and manifesting several pointers of Paragonimiasis, was treated as tuberculosis despite negative sputum AFB; without improving. He then presented up-country in Jos where history led to suspicion and confirmation of Paragonimiasis. By this time he had severe cor-pulmonale and died despite treatment. CONCLUSION: In this current economic downturn in Nigeria which may drive people to cheaper protein sources, a high index of suspicion should be raised for paragonimiasis when a patient presents with chronic cough productive of AFB-negative sputum and haemoptysis.
Assuntos
Paragonimíase/diagnóstico , Paragonimus/isolamento & purificação , Animais , Diagnóstico Diferencial , Evolução Fatal , Humanos , Pneumopatias Parasitárias , Masculino , Nigéria , Paragonimíase/parasitologia , Paragonimus/classificação , Escarro/parasitologia , Tuberculose Pulmonar/diagnósticoRESUMO
Paragonimiasis, or lung fluke disease, is a typical food-borne parasitic zoonosis caused by infection with trematodes belonging to the genus Paragonimus. More than 50 species of Paragonimus have been reported throughout the world, of which seven valid species infect humans, an estimated one million people annually worldwide. Among the seven species, P. westermani, P. heterotremus, and P. skrjabini/P. s. miyazakii, distributed in Asia, are the most important species as the cause of paragonimiasis. Humans acquire infection through the ingestion of raw, pickled or undercooked freshwater crustaceans, 2nd intermediate hosts, or consuming raw meat of wild boar or deer, paratenic hosts. Infections often occur clustered in foci where dietary habits allow transmission of the parasites. Paragonimiasis typically causes a subacute to chronic inflammatory disease of the lungs. The symptoms, including chronic cough, chest pain, dyspnea and hemoptysis, mimic those of tuberculosis and lung cancer. Serologic tests are commonly used for the diagnosis of paragonimiasis, and Praziquantel is the treatment of choice. In this review, the current status of Paragonimus and paragonimiasis in Asia is outlined based on the latest information and findings. We also summarize current trends of paragonimiasis in Japan, which is one of the most endemic area of paragonimiasis in the world, for the better understanding and control of paragonimiasis.
Assuntos
Paragonimíase/tratamento farmacológico , Paragonimíase/epidemiologia , Paragonimus/isolamento & purificação , Animais , Ásia/epidemiologia , Vetores de Doenças , Humanos , Paragonimus/classificação , Praziquantel/uso terapêuticoRESUMO
BACKGROUND: Members of the genus Paragonimus require at least three hosts in their life-cycles. The obligatory first intermediate hosts are freshwater snails. In Vietnam, although seven Paragonimus species have been recorded, the natural first intermediate hosts of almost all species have not been confirmed. The aim of this study was, therefore, to investigate snail hosts of Paragonimus species in Vietnam, and to identify Paragonimus species at intramolluscan stages. METHODS: Freshwater snails were collected from streams in Yen Bai and Quang Tri Provinces, where high prevalences of Paragonimus metacercariae in crab hosts have been reported. Snails were morphologically identified and then examined individually for Paragonimus cercariae using shedding and crushing methods. Chaetomicrocercous cercariae, the morphological class to which Paragonimus cercariae belong, were collected for morphological description and molecular species identification by analyses of ITS2 sequences. The infected snail species were identified based on analyses of nucleotide sequences of the cox1 gene. RESULTS: Three snail species were found to be infected with Paragonimus cercariae at low infection rates, ranging between 0.07-1.0%. The molecular analyses identified them as Sulcospira quangtriensis and 2 species of subfamily Triculinae. In a phylogenetic tree, these two triculine snails were related to the genera Gammatricula and Tricula with low posterior probabilities. Thus we named them as Triculinae sp. 1 and Triculinae sp. 2. Cercariae from the three snail species, Sulcospira quangtriensis, Triculinae sp. 1 and Triculinae sp. 2, were molecularly identified as Paragonimus westermani, P. heterotremus and P. proliferus, respectively. The cercariae of the three species are morphologically similar to each other, but their daughter rediae can be distinguished by the length of the intestine and the number of cercariae per redia. The rediae of P. westermani have a long intestine and each contain 6-8 cercariae. In contrast, those of P. heterotremus and P. proliferus have a short intestine and each redia contain 10-12 and 5-6 cercariae, respectively. CONCLUSIONS: Three snail species, Sulcospira quangtriensis, Triculinae sp. 1 and Triculinae sp. 2, serve as the first intermediate hosts of P. westermani, P. heterotremus and P. proliferus, respectively, in Vietnam. The length of the intestine of rediae and the number of cercariae per redia are valuable characteristics for distinguishing between larvae of these Paragonimus species.
Assuntos
Braquiúros/parasitologia , Paragonimíase/parasitologia , Paragonimus/classificação , Caramujos/parasitologia , Animais , Geografia , Especificidade de Hospedeiro , Larva , Estágios do Ciclo de Vida , Metacercárias , Paragonimus/genética , Paragonimus/isolamento & purificação , Filogenia , Caramujos/classificação , Vietnã/epidemiologiaRESUMO
A 30-year-old male, from a subtropical region of Ecuador, was hospitalized with a 5-year history of persistent cough with rusty brown sputum, chest pain, and progressive dyspnea. The patient underwent thoracic surgery 3 years ago for pleural effusion and subsequently received a 9-month regimen treatment of tuberculosis. However, there was no clinical resolution and symptoms became progressively worse. A chest radiograph and computerized tomography scan showed several small nodules in both lungs. Eggs of Paragonimus spp. were observed in sputum smears, but the smears were negative for acid-fast bacilli. Molecular characterization of eggs by the internal transcribed spacer-2 regions identified them as Paragonimus mexicanus The patient was treated with praziquantel and tested negative parasitologically for 12 months. There was clinical resolution of the cough and expectoration, but dyspnea and chest pain persisted.
Assuntos
Pneumopatias Parasitárias/patologia , Paragonimíase/epidemiologia , Paragonimíase/patologia , Paragonimus/isolamento & purificação , Doenças Pleurais/patologia , Adulto , Animais , Equador/epidemiologia , Humanos , Pneumopatias Parasitárias/tratamento farmacológico , Pneumopatias Parasitárias/parasitologia , Masculino , Paragonimíase/tratamento farmacológico , Paragonimus/classificação , Doenças Pleurais/tratamento farmacológico , Doenças Pleurais/parasitologia , Praziquantel/uso terapêuticoRESUMO
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.
Assuntos
Metacercárias/anatomia & histologia , Metacercárias/genética , Paragonimus/classificação , Animais , Sequência de Bases , Braquiúros/parasitologia , Costa Rica/epidemiologia , DNA de Helmintos/genética , DNA Espaçador Ribossômico/genética , Água Doce/parasitologia , Genes Mitocondriais , Metacercárias/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia de Polarização , Paragonimíase/epidemiologia , Paragonimíase/parasitologia , Paragonimus/genética , Paragonimus/crescimento & desenvolvimento , Paragonimus/ultraestrutura , Filogenia , Análise de Sequência de DNARESUMO
Cathepsin L is a cysteine protease belonging to the papain family. In parasitic trematodes, cathepsin L plays essential roles in parasite survival and host-parasite interactions. In this study, cathepsin L of the lung fluke Paragonimus pseudoheterotremus (PpsCatL) was identified and its molecular biological and immunological features characterized. A sequence analysis of PpsCatL showed that the gene encodes a 325-amino-acid protein that is most similar to P. westermani cathepsin L. The in silico three-dimensional structure suggests that PpsCatL is a pro-enzyme that becomes active when the propeptide is cleaved. A recombinant pro-PpsCatL lacking the signal peptide (rPpsCatL), with a molecular weight of 35 kDa, was expressed in E. coli and reacted with P. pseudoheterotremus-infected rat sera. The native protein was detected in crude worm antigens and excretory-secretory products and was localized in the cecum and in the lamellae along the intestinal tract of the adult parasite. Enzymatic activity of rPpsCatL showed that the protein could cleave the fluorogenic substrate Z-Phe-Arg-AMC after autocatalysis but was inhibited with E64. The immunodiagnostic potential of the recombinant protein was evaluated with an enzyme-linked immunosorbent assay (ELISA) and suggested that rPpsCatL can detect paragonimiasis with high sensitivity and specificity (100 and 95.6 %, respectively). This supports the further development of an rPpsCatL-ELISA as an immunodiagnostic tool.
Assuntos
Antígenos de Helmintos/imunologia , Catepsina L/genética , Catepsina L/imunologia , Proteínas de Helminto/genética , Proteínas de Helminto/imunologia , Paragonimíase/parasitologia , Paragonimus/enzimologia , Sequência de Aminoácidos , Animais , Antígenos de Helmintos/química , Antígenos de Helmintos/genética , Sequência de Bases , Catepsina L/química , Ensaio de Imunoadsorção Enzimática/métodos , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Proteínas de Helminto/química , Humanos , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Paragonimíase/diagnóstico , Paragonimus/classificação , Paragonimus/genética , Paragonimus/isolamento & purificação , Ratos , Ratos Wistar , Alinhamento de SequênciaRESUMO
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.
Assuntos
Doenças do Gato/diagnóstico , Fezes/parasitologia , Felidae/parasitologia , Técnicas de Diagnóstico Molecular/métodos , Paragonimíase/veterinária , Paragonimus/isolamento & purificação , Animais , Doenças do Gato/epidemiologia , Doenças do Gato/parasitologia , Gatos , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Variação Genética , Genótipo , Paragonimíase/diagnóstico , Paragonimíase/epidemiologia , Paragonimíase/parasitologia , Paragonimus/classificação , Paragonimus/genética , Vietnã/epidemiologiaRESUMO
Paragonimus macrorchis is rather a rare species with sporadic discovery reports. To date, little is known about morphological features and the molecular phylogenetic status of P. macrorchis. Here we provide such information on P. macrorchis, of which metacercariae were collected from freshwater crabs in Khammouane Province, central Lao PDR. After morphological observation, metacercariae were excysted and were injected intra-peritoneally into Mongolian gerbils. Paragonimus adult worms were collected from the lungs of experimental gerbils 45 days after infection. A small piece of body tissue was cut at the posterior part of each adult worm for genomic DNA extraction. Then, the adult worms were stained and mounted for morphological identification. The second internal transcribed spacer region (ITS2) of rDNA and partial cytochrome c oxidase subunit 1 (cox1) gene were amplified using PCR method and sequenced. The results of morphological identification of metacercariae and adult worms together with their DNA sequences of ITS2 and partial cox1 gene clearly show that the specimens we collected in the central Lao PDR were P. macrorchis. Phylogenetic analyses revealed that P. macrorchis forms an independent cluster from other Paragonimus species in Asia.
Assuntos
DNA de Helmintos/genética , Pneumopatias Parasitárias/parasitologia , Paragonimíase/parasitologia , Paragonimus/classificação , Paragonimus/isolamento & purificação , Animais , Sequência de Bases , Braquiúros/parasitologia , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Gerbillinae/parasitologia , Laos , Pulmão/parasitologia , Metacercárias/genética , Dados de Sequência Molecular , Tipagem Molecular , Paragonimus/genética , Filogenia , Análise de Sequência de DNARESUMO
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.
Assuntos
Braquiúros/parasitologia , Variação Genética , Paragonimíase/parasitologia , Paragonimus/classificação , Paragonimus/genética , Animais , Gatos , China , Feminino , Humanos , Índia , Masculino , Dados de Sequência Molecular , Paragonimus/crescimento & desenvolvimento , Paragonimus/isolamento & purificação , Filogenia , Tailândia , VietnãRESUMO
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 pulmonary paragonimiasis is commonly misdiagnosed and treated as tuberculosis and although studies have demonstrated the efficacy of praziquantel and triclabendazole for the treatment of human infections, neither drug is available in Ecuador. Official data recorded from 1978-2007 indicate an annual incidence of 85.5 cases throughout the 19 provinces, with an estimated 17.2% of the population at risk of infection. There are no current data on the incidence/prevalence of infection, nor is there a national control programme.
Assuntos
Pneumopatias Parasitárias/epidemiologia , Metacercárias/isolamento & purificação , Paragonimíase/epidemiologia , Paragonimus/classificação , Animais , Anti-Helmínticos/uso terapêutico , Astacoidea/parasitologia , Braquiúros/parasitologia , Doença Crônica , Equador/epidemiologia , Humanos , Pneumopatias Parasitárias/diagnóstico , Pneumopatias Parasitárias/tratamento farmacológico , Doenças Negligenciadas/epidemiologia , Paragonimíase/diagnóstico , Paragonimíase/tratamento farmacológicoRESUMO
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 pulmonary paragonimiasis is commonly misdiagnosed and treated as tuberculosis and although studies have demonstrated the efficacy of praziquantel and triclabendazole for the treatment of human infections, neither drug is available in Ecuador. Official data recorded from 1978-2007 indicate an annual incidence of 85.5 cases throughout the 19 provinces, with an estimated 17.2% of the population at risk of infection. There are no current data on the incidence/prevalence of infection, nor is there a national control programme.
Assuntos
Animais , Humanos , Pneumopatias Parasitárias/epidemiologia , Metacercárias/isolamento & purificação , Paragonimíase/epidemiologia , Paragonimus/classificação , Anti-Helmínticos/uso terapêutico , Astacoidea/parasitologia , Braquiúros/parasitologia , Doença Crônica , Equador/epidemiologia , Pneumopatias Parasitárias/diagnóstico , Pneumopatias Parasitárias/tratamento farmacológico , Doenças Negligenciadas/epidemiologia , Paragonimíase/diagnóstico , Paragonimíase/tratamento farmacológicoAssuntos
Paragonimíase/epidemiologia , Paragonimus/patogenicidade , Animais , Anti-Helmínticos/uso terapêutico , Evolução Biológica , Humanos , Paragonimíase/fisiopatologia , Paragonimíase/terapia , Paragonimíase/transmissão , Paragonimus/classificação , Paragonimus/genética , Filogenia , Procedimentos Cirúrgicos Operatórios , ZoonosesRESUMO
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.
Assuntos
Braquiúros/parasitologia , Metacercárias/isolamento & purificação , Paragonimus/isolamento & purificação , Animais , Sequência de Bases , Análise por Conglomerados , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Metacercárias/classificação , Metacercárias/genética , México , Microscopia , Dados de Sequência Molecular , Paragonimus/anatomia & histologia , Paragonimus/classificação , Paragonimus/genética , Filogenia , RNA Ribossômico 28S/genética , Análise de Sequência de DNARESUMO
Paragonimiasis is a parasitic lung infection caused by lung flukes of the genus Paragonimus, with most cases reported from Asia and caused by P. westermani following consumption of raw or undercooked crustaceans. With the exception of imported P. westermani cases in immigrants, in travelers returning from areas of disease endemicity, and in clusters of acquired cases following consumption of imported Asian crabs, human paragonimiasis caused by native lung flukes is rarely described in the United States, which has only one indigenous species of lung fluke, Paragonimus kellicotti. Clinicians should inquire about the consumption of raw or undercooked freshwater crabs by immigrants, expatriates, and returning travelers, and the consumption of raw or undercooked crayfish in U.S. freshwater river systems where P. kellicotti is endemic when evaluating patients presenting with unexplained fever, cough, rales, hemoptysis, pleural effusions, and peripheral eosinophilia. Diagnostic evaluation by specific parasitological, radiological, serological, and molecular methods will be required in order to differentiate paragonimiasis from tuberculosis, which is not uncommon in recent Asian immigrants. All cases of imported and locally acquired paragonimiasis will require treatment with oral praziquantel to avoid any potential pulmonary and cerebral complications of paragonimiasis, some of which may require surgical interventions.
Assuntos
Paragonimíase/parasitologia , Animais , Decápodes/parasitologia , Humanos , Paragonimus/classificação , Paragonimus/isolamento & purificação , Caramujos/parasitologia , Estados UnidosRESUMO
Paragonimus mexicanus is the causal agent of human paragonimiasis in several countries of the Americas. It is considered to be the only species of the genus present in Mexico, where it is responsible for human infection. Through the investigation of P. mexicanus specimens from several places throughout Mexico, we provide morphological, molecular and geographical evidence that strongly suggests the presence of at least three species from this genus in Mexico. These results raise questions regarding the diagnosis, treatment, prophylaxis and control of human paragonimiasis in Mexico. We also provide a brief discussion regarding biodiversity inventories and the convenience of providing molecular and morphological information in biodiversity studies.
Assuntos
Código de Barras de DNA Taxonômico , Paragonimus/genética , Animais , Biodiversidade , Humanos , Paragonimus/anatomia & histologia , Paragonimus/classificação , Paragonimus/isolamento & purificação , Alinhamento de Sequência , Especificidade da EspécieRESUMO
Paragonimus bangkokensis and Paragonimus harinasutai, which are morphologically distinguishable species, often co-infect in the same crab intermediate hosts. Recent molecular phylogenetic analyses revealed that these two species are genetically close to each other and are considered as the sister species. While we have been studying Paragonimus adult worms obtained from the lungs of a cat experimentally infected with Paragonimus metacercariae which were morphologically identified as P. harinasutai collected from central Viet Nam, one out of 6 adult worms has grouped cuticular spines, which is a feature of P. bangkokensis. By molecular analyses, the CO1 sequence of this specimen was identical with that of P. bangkokensis, but the ITS2 and the D2 region of 28S rDNA sequences showed a two peak pattern. Then, PCR products of the ITS2 and the D2 region of 28S rDNA sequences were ligated to TOPO vector and subcloned to determine the heterozygosity. Two types of sequences were obtained from each ITS2 and D2 region of 28S; one was identical with P. harinasutai and the other with P. bangkokensis. Taking all these morphological and molecular data together, we identified this adult worm as a hybrid specimen of P. bangkokensis and P. harinasutai.