RESUMO
Here we describe a new species of the genus Saccocoelioides found parasitizing Astyanax dissimilis Garavello & Sampaio, Psalidodon bifasciatus (Garavello and Sampaio) and Bryconamericus ikaa Casciotta, Almirón & Azpelicueta from the Iguazu National Park, Misiones province, Argentina. Saccocoelioides miguelmontesi n. sp. was studied based on morphological and molecular (28S rDNA and COI mtDNA sequences) data. The COI mtDNA tree indicated that the specimens collected from the three fish hosts are conspecific, with an intragroup p-distance of 0%. The new species shows an intermediate morphological configuration between the diminutive and robust forms described for Saccocoelioides by Curran (2018). Although, in the 28S rDNA tree, it is placed in a well-supported clade with the two robust species analysed (S. elongatus and S. magnus; p-distance of 1 and 2%, respectively), it differs from the robust group by the range of body size, mature egg size, oral and ventral sucker size, sucker ratio, oral sucker to pharynx ratio, and post-cecal or post-testis/body length percentage. Our results led us to redefine the robust group as having eggs shorter or equal in length to the pharynx. Saccocoelioides miguelmontesi n. sp. the 10th species reported from Argentina and the 7th species within the robust group.
Assuntos
Characidae , Doenças dos Peixes , Trematódeos , Infecções por Trematódeos , Masculino , Animais , Rios , Filogenia , Óvulo , DNA Ribossômico , DNA Mitocondrial , RNA Ribossômico 28S/genéticaRESUMO
BACKGROUND: Soil-transmitted helminths (STHs) are widely distributed throughout the world. Various factors, including the environment, socioeconomic characteristics, and access to water and sanitation, play an important role in the spread and persistence of these parasites within communities. They, in turn, affect the growth and development of members of the community, especially children. Studies in the northern provinces of Argentina have shown variable prevalence of STHs, but the factors associated with their presence have not been completely elucidated. OBJECTIVE: This cross-sectional study aimed to identify the socioeconomic and environmental factors related to STH infection in indigenous villages located in Puerto Iguazú (Misiones), Argentina. METHODS: Between 2018 and 2019, stool samples were collected from individuals ≥1 year residing in 3 villages: Mini-Marangatú, Yriapú, and Fortín Mbororé. Standard parasitological methods were used to determine STH prevalence. Standardized questionnaires were used to assess participants' habits, customs, and household characteristics, and environmental data were obtained through satellite imagery. Multilinear regression with Akaike information criterion stepwise variables was used to explore relevant associations. RESULTS: A total of 342 individuals from the 3 villages participated in this study. The prevalence of STHs varied across villages: 89.6% (43/48), in Mini-Marangatú, 80.8% (101/125) in Yriapú, and 68.5% (115/169) in Fortín Mbororé. Notably, there was a significant difference in hookworm infection among the villages (P=.02). The analysis highlighted the significant influence of specific environmental factors on STH presence and spatial distribution, particularly in relation to hookworm infection. Vegetation patterns represented by the Vegetation Heterogeneity Index, created ad hoc for this study, emerged as a critical factor, with 2 significant predictors related to it (P=.002 and P=.004) alongside impervious surface density with a significant predictor (P<.001). The multilinear regression model yielded a high F test score (F108=4.75, P<.001), indicating a strong fit (R2=0.5465). Furthermore, socioeconomic factors, including walking barefoot in houses with dirt floors and overcrowding, were significantly correlated with hookworm infection intensity (P<.001 and P=.001, respectively). We also used the multilinear regression model to calculate hookworm infection intensity (F110=21.15, P<.001; R2=0.4971). CONCLUSIONS: Our study underscores the complexity of STH transmission, as villages with similar living conditions and environmental characteristics displayed varied STH prevalence and spatial distribution. Specific environmental factors, such as vegetation pattern and impervious surface density, played major roles in STH presence, demonstrating the crucial relationship between environmental factors and hookworm infection distribution. Moreover, our findings emphasize the significant influence of socioeconomic factors on hookworm infection intensity. By gaining insights into this complex interplay, our research contributes to a better understanding of STH transmission characteristics, thereby informing targeted public health interventions for effective control.
Assuntos
Infecções por Uncinaria , Saúde Pública , Criança , Humanos , Estudos Transversais , Argentina , SaneamentoRESUMO
In Argentina, the family Diplostomidae is composed of eight genera: Austrodiplostomum Szidat & Nani; Diplostomum von Nordmann; Dolichorchis Dubois; Hysteromorpha Lutz; Neodiplostomum Railliet; Posthodiplostomum Dubois; Sphincterodiplostomum Dubois; and Tylodelphys Diesing. During a parasitological survey of fishes from the Iguazú National Park we detected diplostomid metacercariae in the brain of Erythrinus cf. erythrinus. Fish were caught using crab traps, transported alive to the field laboratory, cold-anaesthetized and euthanized by cervical dissection. Some metacercariae were heat-killed in water and fixed in 10% formalin and others were preserved in alcohol 96% for DNA extraction. They were sequenced for the partial segment of the 28S rDNA, internal transcribed spacer (ITS) rDNA and cytochrome c oxidase subunit I (COI) mtDNA genes. Phylogenetic reconstruction was carried out using Bayesian inference and the proportion (p) of absolute nucleotide sites (p-distance) was obtained. In the 28S rDNA tree, the metacercaria sequenced grouped as Dolichorchis sp. The COI mtDNA p-distance between the metacercariae with Dolichorchis lacombeensis was 0.01. There is a small number of ITS sequences for the Diplostomidae family deposited in the GenBank. The oral sucker, ventral sucker, holdfast organ and the distance between oral and ventral suckers are larger in the adult compared with the metacercariae. Additionally, hind-body length and width are larger in the adult due to the development of the genital complex. Further studies using an integrative approach will help confirm the affiliation of other species to the genus Dolichorchis.
Assuntos
Caraciformes , Doenças dos Peixes , Trematódeos , Infecções por Trematódeos , Animais , Argentina , Teorema de Bayes , Encéfalo , DNA Mitocondrial/genética , DNA Ribossômico/genética , Metacercárias/genética , Parques Recreativos , Filogenia , Infecções por Trematódeos/veterináriaRESUMO
BACKGROUND: Intestinal parasites (IPs) are widely distributed worldwide and are one of the major contributors to gastrointestinal disease. Their prevalence is associated with poor access to water, sanitation and hygiene (WASH). The objective of this study was to identify the prevalence of IPs, including soil-transmitted helminths (STH), and their relation to socioeconomic characteristics, as well as a first approach to molecularly characterize the types of Giardia intestinalis, Blastocystis spp. and Entamoeba histolytica present in an indigenous community from Puerto Iguazú, Misiones, Argentina. METHODS: A cross-sectional study was conducted in the rural settlement of Fortin Mbororé between January and March 2018. Socioeconomic variables, household characteristics, and stool and blood samples were collected. Standard coprological techniques were used to analyze stool samples, and a complete hemogram was performed on the blood samples. Giardia intestinalis microscopy-positive samples were genetically typed by the ß-giardin (bg) gene. Molecular identification of Blastocystis spp. subtypes and E. histolytica were carried out by amplification and sequencing of a partial fragment of the small subunit ribosomal RNA gene (SSU rDNA). RESULTS: The overall prevalence of IPs was 92.7%, with 72.0% specifically for hookworm. IPs were significantly more prevalent in preschool- and school-age children (P < 0.05). No formal education (P = 0.035), the presence of unimproved floors (P = 0.001) and overcrowding (P = 0.005) were significantly associated with IP infection. Hookworm was associated with anemia (P = 0.019). Molecular characterization revealed the presence of E. histolytica sub-assemblages AII (12.5%), AIII (87.5%) and BIV (100%); one case of sub-assemblage D for G. intestinalis; and the presence of subtypes ST1 (14.8%), ST2 (14.8%) and ST3 (70.4%) of Blastocystis spp. CONCLUSIONS: Protozoans detected in this study are transmitted mainly through water contaminated with fecal matter, evidencing the need to improve the quality of water and sanitation for the inhabitants of Fortín Mbororé. Molecular characterization showed that domestic animals can be implicated in the zoonotic transmission of G. intestinalis and Blastocystis spp. to humans. A hyperendemic area for STH was found, with hookworm prevalence greater than 50%. Therefore, improvements in WASH as well as mass deworming programs need to be implemented in this area to control and decrease the prevalence of IPs in general and STH in particular.
Assuntos
Infecções por Blastocystis/epidemiologia , Blastocystis/genética , Entamoeba histolytica/genética , Entamebíase/epidemiologia , Giardia lamblia/genética , Giardíase/epidemiologia , Enteropatias Parasitárias/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Argentina/epidemiologia , Infecções por Blastocystis/sangue , Criança , Pré-Escolar , Estudos Transversais , Entamebíase/sangue , Fezes/parasitologia , Feminino , Giardíase/sangue , Humanos , Lactente , Enteropatias Parasitárias/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , População Rural/estatística & dados numéricos , Adulto JovemRESUMO
During a parasitological survey of fishes at Iguazu National Park, Argentina, specimens belonging to the allocreadiid genus Auriculostoma were collected from the intestine of Characidium heirmostigmata. The erection of the new species is based on a unique combination of morphological traits as well as on phylogenetic analysis. Auriculostoma guacurarii n. sp. resembles four congeneric species - Auriculostoma diagonale, Auriculostoma platense, Auriculostoma tica and Auriculostoma totonacapanensis - in having smooth and oblique testes, but can be distinguished by a combination of several morphological features, hosts association and geographic distribution. Morphologically, the new species can be distinguished from both A. diagonale and A. platense by the egg size (bigger in the first and smaller in the last); from A. tica by a shorter body length, the genital pore position and the extension of the caeca; and from A. totonacapanensis by the size of the oral and ventral sucker and the post-testicular space. Additionally, one specimen of Auriculostoma cf. stenopteri from the characid Charax stenopterus (Characiformes) from La Plata River, Argentina, was sampled and the partial 28S rRNA gene was sequenced. The phylogenetic analysis revealed that A. guacurarii n. sp. clustered with A. tica and these two as sister taxa to A. cf. stenopteri. The new species described herein is the tenth species in the genus and the first one parasitizing a member of the family Crenuchidae.
Assuntos
Caraciformes , Doenças dos Peixes , Trematódeos , Infecções por Trematódeos , Animais , Argentina , Caraciformes/parasitologia , Doenças dos Peixes/parasitologia , Filogenia , Trematódeos/anatomia & histologia , Trematódeos/classificação , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/veterináriaRESUMO
Adult forms of members of the Callodistomidae always parasitize the gallbladder of freshwater fishes and occur in Africa and America. This study provides a description of a new South American species belonging in Prosthenhystera from the gallbladder of a characid fish (Bryconamericus ikaa), and ribosomal gene sequences (28S rDNA and ITS1-5.8S-ITS2) are used to demonstrate molecular differences between the new species and congeners as well as explore interrelationships among congeners. Additionally, the first cytological analysis is conducted for a member of the family to determine chromosome number and arrangement. Prosthenhystera gattii n. sp. most closely resembles Prosthenhystera caballeroi in morphology, but the vitellarium is more extensive reaching anterior to the caecal bifurcation in the new species and the uterus is confined to the hindbody in P. gattii n. sp., whereas it extends to the level of the pharynx in P. caballeroi. Also, the testes, cirrus sac, seminal receptacle and the ratio of body length to width are larger in P. gattii n. sp. Independent Bayesian inference analyses of 28S rDNA and ITS1-5.8S-ITS2 sequence fragments produced phylograms that showed P. gattii n. sp. is more similar to Prosthenhystera obesa + Prosthenhystera oonastica than P. caballeroi + two unidentified species of Prosthenhystera, but with poor posterior probability support for the node in the ITS1-5.8S-ITS2-based phylogram. Further, the genetic distance between P. oonastica and P. gattii n. sp. are the largest among Prosthenhystera spp. Cytological analysis revealed ten metacentric chromosomes, which is fewer than the 12-18 chromosomes present in species from the closely related Gorgoderidae.
Assuntos
Characidae/parasitologia , Vesícula Biliar/parasitologia , Filogenia , Trematódeos/anatomia & histologia , Trematódeos/classificação , Infecções por Trematódeos/veterinária , Animais , Argentina , Teorema de Bayes , DNA de Helmintos/genética , DNA Espaçador Ribossômico/genética , Feminino , Doenças dos Peixes/parasitologia , Água Doce/parasitologia , Masculino , RNA Ribossômico 28S/genéticaRESUMO
Abstract: Orchid bees were surveyed at Parque Nacional do Iguaçu, the largest remnant of Seasonal Semideciduous Forest in Brazil. Seven species were collected, and Eufriesea violacea (Blanchard) was the most common species, followed by Euglossa annectans Dressler. The observed species richness and species composition agree with what is known for the local euglossine faunas in fragments of Seasonal Semideciduous Forest of southern and southeastern Brazil. On the other hand, the abundance of individuals was remarkably low. The occurrence of a severe winter in 2013 and the collection of several males in other fragments suggest that this noteworthy low abundance can be fortuitous.
Resumo: Abelhas-das-orquídeas foram amostradas no Parque Nacional do Iguaçu, o maior fragmento de Floresta Estacional Semidecidual do Brasil. Sete espécies foram coletadas e Eufriesea violacea (Blanchard) foi a espécie mais comum, seguida por Euglossa annectans Dressler. A riqueza e composição de espécies observadas concordam com o que se conhece para as faunas locais de abelhas euglossinas em fragmentos de Floresta Estacional Semidecidual. Por outro lado, a abundância de indivíduos foi notavelmente baixa. A ocorrência de um inverno severo em 2013 e a coleta de muitos machos em outros fragmentos sugerem que tal baixa abundância pode ser fortuita.
RESUMO
The giant African snail Achatina fulica is an invasive mollusk native to Africa, the first record in Argentina was in Puerto Iguazú, in northeastern Argentina in 2010. Recently it was reported in Corrientes Province. This snail can act as an intermediate host of Metastrongyloidea nematodes of importance in public health as: Angiostrongylus cantonensis, Angiostrongylus costaricensis and Angiostrongylus vasorum. Taking into account the presence of A. fulica in Argentina, the objectives of this study is to assess the presence of Metastrongyloidea nematodes in this mollusk species in Puerto Iguazú, Misiones, close to the international border with Brazil and Paraguay. A total of 451 samples were collected from February 2014 to November 2015. The snails were processed using a digestion technique to recover the parasites. A total of 206 nematodes larvae were founded in the digestion solution of 10 hosts (P=2%; MA=0.5; MI=21). Third larval stage (L3) nematodes identified as Aelurostrongylus abstrusus were founded parasitizing the snails. No other larval stage was observed. This species has veterinary importance because it causes 'aelurostrongilosis', also known as feline strongyloidosis. This study constitutes the first record of a Metastrongyloidea nematode in A. fulica in Argentina and also highlights the susceptibility of this mollusk as intermediate host of other helminthes of health importance. The present study suggests that there is a need to establish an epidemiological monitoring system in order to prevent the possible installation of an infected mollusks focus.
Assuntos
Doenças do Gato/parasitologia , Metastrongyloidea/isolamento & purificação , Caramujos/parasitologia , Infecções por Strongylida/veterinária , Animais , Argentina/epidemiologia , Doenças do Gato/epidemiologia , Gatos , Reservatórios de Doenças , Espécies Introduzidas , Larva , Saúde Pública , Infecções por Strongylida/epidemiologia , Infecções por Strongylida/parasitologiaRESUMO
The Iguazu river is a tributary of the left margin of the Paraná river, isolated from this basin about 22 million years ago with the appearance of the Iguazu Falls. The Iguazu river is characterized by high endemism due to two factors: its rugged topography and the old isolation caused by formation of the Iguazu Falls. This study analyzed cytogenetically a population of Glanidium ribeiroi collected in a region at the final stretch of this basin, by Giemsa staining, C-banding, impregnation by silver nitrate, and FISH with probes of 5S rDNA, 18S rDNA, telomeric sequence [TTAGGG]n, and [GATA]n repeats. The diploid number was equal to 58 chromosomes. The heterochromatin was present in the terminal region of almost all chromosomes. The Ag-NORs were simple and presented interstitially on the short arm of the submetacentric pair 14, which was confirmed by FISH with 18S rDNA probe. The 5S rDNA-FISH marked only the submetacentric pair 16 on the long arm in interstitial position. The FISH with [TTAGGG]n probe presented all telomeres labeled as expected, with an absence of Interstitial Telomeric Sequence (ITS). The repetitive [GATA]n sequence was dispersed throughout the genome, with preferential location in the terminal region of all chromosomes. The data obtained are discussed herein with other species of Auchenipteridae, and other previously analyzed populations of G. ribeiroi from the Iguazu river, verifying differences among these populations, which should be mainly related to the rugged topography of this basin.(AU)
O rio Iguaçu é um afluente da margem esquerda do rio Paraná, que foi separado desta bacia a aproximadamente 22 milhões de anos com o surgimento das Cataratas do Iguaçu. Esse rio é caracterizado por elevado endemismo, o que se deve a dois fatores: sua acidentada topografia e ao antigo isolamento proporcionado pela formação das cataratas. No presente trabalho foi analisado cromossomicamente uma população de Glanidium ribeiroi coletada em uma região que corresponde ao trecho final desse rio, através de coloração com Giemsa, bandamento-C, impregnação pelo nitrato de prata e FISH com sondas de rDNA 5S, rDNA 18S, sequência telomérica [TTAGGG]n e repetições [GATA]n. O número diploide encontrado foi igual a 58 cromossomos. A heterocromatina se mostrou dispersa na região terminal de quase todos os cromossomos. As Ag-RONs são simples e presentes no braço curto em posição intersticial do par submetacêntrico 14, o que foi confirmado pela FISH com rDNA 18S. O rDNA 5S marcou apenas o par submetacêntrico 16 no braço longo em posição intersticial. A hibridização com sonda [TTAGGG]n revelou todos os telômeros marcados conforme esperado e ausência de Sequência Telomérica Intersticial (ITS). As repetições [GATA]n se apresentaram dispersas no genoma da espécie, com preferencial localização na região terminal de todos os cromossomos. Os dados aqui obtidos são discutidos com os de outras espécies de Auchenipteridae, especialmente de G. ribeiroi anteriormente analisados do rio Iguaçu. Diferenças populacionais são constatadas em decorrência do isolamento geográfico ocasionado pelas inúmeras cachoeiras existentes no curso do rio Iguaçu.(AU)
Assuntos
Animais , Masculino , Feminino , /genética , Variação Genética , Cariótipo , Brasil , RiosRESUMO
Abstract The Iguazu river is a tributary of the left margin of the Paraná river, isolated from this basin about 22 million years ago with the appearance of the Iguazu Falls. The Iguazu river is characterized by high endemism due to two factors: its rugged topography and the old isolation caused by formation of the Iguazu Falls. This study analyzed cytogenetically a population of Glanidium ribeiroi collected in a region at the final stretch of this basin, by Giemsa staining, C-banding, impregnation by silver nitrate, and FISH with probes of 5S rDNA, 18S rDNA, telomeric sequence [TTAGGG]n, and [GATA]n repeats. The diploid number was equal to 58 chromosomes. The heterochromatin was present in the terminal region of almost all chromosomes. The Ag-NORs were simple and presented interstitially on the short arm of the submetacentric pair 14, which was confirmed by FISH with 18S rDNA probe. The 5S rDNA-FISH marked only the submetacentric pair 16 on the long arm in interstitial position. The FISH with [TTAGGG]n probe presented all telomeres labeled as expected, with an absence of Interstitial Telomeric Sequence (ITS). The repetitive [GATA]n sequence was dispersed throughout the genome, with preferential location in the terminal region of all chromosomes. The data obtained are discussed herein with other species of Auchenipteridae, and other previously analyzed populations of G. ribeiroi from the Iguazu river, verifying differences among these populations, which should be mainly related to the rugged topography of this basin.
Resumo O rio Iguaçu é um afluente da margem esquerda do rio Paraná, que foi separado desta bacia a aproximadamente 22 milhões de anos com o surgimento das Cataratas do Iguaçu. Esse rio é caracterizado por elevado endemismo, o que se deve a dois fatores: sua acidentada topografia e ao antigo isolamento proporcionado pela formação das cataratas. No presente trabalho foi analisado cromossomicamente uma população de Glanidium ribeiroi coletada em uma região que corresponde ao trecho final desse rio, através de coloração com Giemsa, bandamento-C, impregnação pelo nitrato de prata e FISH com sondas de rDNA 5S, rDNA 18S, sequência telomérica [TTAGGG]n e repetições [GATA]n. O número diploide encontrado foi igual a 58 cromossomos. A heterocromatina se mostrou dispersa na região terminal de quase todos os cromossomos. As Ag-RONs são simples e presentes no braço curto em posição intersticial do par submetacêntrico 14, o que foi confirmado pela FISH com rDNA 18S. O rDNA 5S marcou apenas o par submetacêntrico 16 no braço longo em posição intersticial. A hibridização com sonda [TTAGGG]n revelou todos os telômeros marcados conforme esperado e ausência de Sequência Telomérica Intersticial (ITS). As repetições [GATA]n se apresentaram dispersas no genoma da espécie, com preferencial localização na região terminal de todos os cromossomos. Os dados aqui obtidos são discutidos com os de outras espécies de Auchenipteridae, especialmente de G. ribeiroi anteriormente analisados do rio Iguaçu. Diferenças populacionais são constatadas em decorrência do isolamento geográfico ocasionado pelas inúmeras cachoeiras existentes no curso do rio Iguaçu.