Distribución espacial de los Genotipos de Echinococcus granulosus sensu lato por hospedero en el continente americano. Revisión sistemática / Spatial distribution of Echinococcus granulosus sensu lato genotypes in the american continent

BACKGROUND: Knowledge of the distribution cystic is required for its territorial control. Aim: To describe the spatial distribution of Echinococcus granulosus sensu lato genotypes by host in the American continent. MATERRIAL AND METHODS: A systematic review of studies from the American continent, related to genotypes of the E. granulosus s.l complex were included, including any host species, without restriction of language or year of publication. Sensitive searches were performed based on sensitive searches from PubMed, EMBASE, ScienceDirect, SCOPUS and WoS; SciELO and BIREME-BVS and Trip Database. MeSH and free terms were used, including articles up to December 2020. Cartography was carried out with the Arc Map 10® program, using a world geodetic system. Result variables sought were genotype, host, geographic location, year of publication, number of samples, genes used for genotyping. RESULTS: From 1123 retrieved studies retrieved, 53 met the inclusion and exclusion criteria. The studies analyzed represent 3,397 samples from humans and animals. Thirty six percent of articles were published in the five-year period 2016-2020. Reports were mainly from Argentina (27.9%), Brazil (20.6%) and Chile (13.2%). The most reported genotypes globally were G1-G3 (47.3%), G7 (15.3%), G5 (14.6%) and G6 (13.3%). A predominance of G1-G3 and G6 genotypes was verified in South America, G8 and G10 in North America, and "epidemiological silence" in Central America and the Caribbean. Conclusions: Spatial analysis allows defining the relationship of territories and cases with their own characteristics, which can help to plan control interventions.

Genotipos de Echinococcus granulosus en hidatidosis humana alrededor del mundo: revisión sistemática / Echinococcus granulosus genotypes verified in human hydatid disease around the world: systematic review

Resumen Introducción: La evidencia sobre las características genotípicas de la infección por Echinococcus granulosus en humanos es escasa. Objetivo: Desarrollar un resumen de la evidencia disponible respecto a genotipos de E. granulosus verificados en hidatidosis humana en el mundo. Material y Métodos: Revisión sistemática. Se incluyeron artículos relacionados con genotipos de E. granulosus, en humanos, sin restricción de lenguaje ni método de secuenciación; publicados entre 1990-2019. Se realizó una búsqueda sistemática en WoS, EMBASE, MEDLINE, SCOPUS, Trip Database, BIREME, SciELO, LILACS, IBECS y OPS-OMS. Las variables en estudio fueron: año de publicación, país de origen, número de muestras, órganos parasitados, marcador molecular utilizado y genotipo identificado. Se aplicó estadística descriptiva. Resultados: Se identificaron 701 artículos relacionados; 62 cumplieron los criterios de selección, representando 1.511 muestras. La evidencia existente fue publicada entre 1994 y 2019 y proviene principalmente de Irán (45,2%). El método de secuenciación más utilizado fue amplificación por reacción de polimerasa en cadena más secuenciación tipo Sanger con genotipificación del gen cox1 (79,0%). Los genotipos identificados con mayor frecuencia fueron G1 (49,1%) y el complejo G1/G3 (32,2%). Conclusión: Las publicaciones relacionadas con genotipos de E. granulosus en humanos son escasas y heterogéneas. Eg G1 representa la mayor parte de la carga global mundial.

Abstract Background: The evidence regarding genotypic characteristics of Echinococcus granulosus infection in humans worldwide is scarce. Aim: To develop a synthesis of the available evidence regarding genotypes of E. granulosus verified in humans worldwide. Methods: Systematic review. Articles related with genotypes of E. granulosus, in humans, without language neither genotyped method restriction, published between 1990-2019 were included. A systematic in WoS, EMBASE, MEDLINE, SCOPUS, Trip Database, BIREME, SciELO, LILACS, IBECS, and PAHO-WHO was carried out. In study variables were year of publication, country, number of samples, host and parasite organs, genotype identified, molecular marker and genes. Descriptive statistics were applied. Results: 701 related articles were identified; 62 fulfilled selection criteria, representing 1,511 samples. The existing evidence was published between 1994 and 2019; and mainly comes from Iran (45.2%). The most commonly used sequencing method was PCR amplification and Sanger type sequencing with partial or total genotyping of the cox1 gene. Genotyped method most frequently used was cox1 (79,0%). Genotypes most frequently identified were G1 and G1/G3 complex (49.1% and 32.2%). Conclusions: Publications related to genotypes of Eg in humans are scarce, heterogeneous, and presenting differing results. Eg G1/G3 accounts for most of the global burden worldwide.

Aspectos generales del perfil proteómico del Echinococcus granulosus / General aspects of the proteomic profile of Echinococcus granulosus

La información disponible referente a las características proteómicas del E. granulosus es escasa (no supera los 50 estudios publicados); y nos parece que la identificación proteómica, podría mejorar la comprensión de algunas características bioquímicas e inmunológicas de la Equinococosis Quística (EQ). De tal modo que el proteoma de E. granulosus aún no está bien descrito. Sólo existen reportes de algunas secuencias de proteínas. El objetivo de este manuscrito fue comentar algunos aspectos de la evidencia existente respecto de los estudios del perfil proteómico del E. granulosus. Se recomienda el estudio de al menos el quiste y su pared, el líquido hidatídico y la víscera del hospedero. Para ello, existen metodologías que han sido empleadas para estudiar las características proteómicas de la EQ. Entre ellas, destacan SDS-PAGE, electroforesis bidimensional combinada con Western Blot, inmunoanálisis, y espectrometría de masas mediante técnicas MALDI-TOF. Se han identificado una serie de proteínas en muestras de EQ. Algunas de ellas, asociadas a procesos inmunológicos, de gluconeogénesis, glucogenolisis y glucogénesis. Por otra parte, se ha documentado la liberación de exosomas al líquido hidatídico por parte de los protoescólex y la capa germinativa; estructuras en las que se han identificado factores de virulencia asociados con la supervivencia del quiste. No obstante lo anteriormente señalado, se requiere de múltiples estudios exhaustivos en la materia para comprender mejor la caracterización perfil proteómico del E. granulosus.

The information available regarding the proteomic characteristics of E. granulosus is scarce; and it seems that the proteomic identification could improve the understanding of some biochemical and immunological characteristics of cystic echinococcosis (CE). So, the proteome of E. granulosus is still not well described yet. There are only reports of some protein sequences. The objective of this manuscript was to comment on some aspects of the existing evidence regarding studies of the proteomic profile of E. granulosus. The study of at least the cyst and its wall, the hydatid fluid and the viscera of the host are recommended. There are a series of methodologies that have been used to study the proteomic characteristics of EQ. These include SDS-PAGE, bidimensional electrophoresis combined with Western Blot, immunoassay, and mass spectrometry using MALDI-TOF techniques. A series of proteins have been identified in CE samples. Some of them, associated with immune response, gluconeogenesis, glycogenolysis and glycogenesis. On the other hand, release of exosomes to the hydatid fluid by protoescolex and germinative layer has been documented (associated virulence factors have been identified in these structures). Notwithstanding the foregoing, it requires multiple exhaustive studies in the field to better understand the characterization of the proteomic profile of E. granulosus.

Molecular epidemiology of cystic echinococcosis: genotypic characterization in humans and different livestock / Epidemiología molecular de la equinococosis quística: caracterización genotípica en humanos y diferentes animales

Echinococcus Granulosus (EG) is the major cause of cystic echinococcosis in humans and livestock in the world. In Chile is a zoonosis of great importance. The most frequently affected geographic areas are the Regions of Aysén, Los Rios, Los Lagos, Coquimbo and the Araucanía. Hence, it was discovered that in endemic areas of hydatidosis there could be several strains and genotypes of EG. In addition, there is evidence that some strains and genotypes are more infectious for human beings than others. This interesting phenomenon of the biology of EG has been studied using molecular biology techniques based on polymerase chain reaction (PCR) and DNA sequence analysis, which has made it possible to characterize the cestode species complex called EG sensu lato (s l) as being comprised of EG sensu stricto (s.s.) (Genotypes G1-G3), E. equinus (G4), E. ortleppi (G5) and E. canadensis (G6-G10), which present an important phenotypic variation detectable in characteristics of the biological cycle, specificity of the intermediate host, pattern of development, pathogenicity, antigenicity, transmission dynamics and, consequently, in the measures needed to control the disease. The aim of this manuscript is to describe the different genotypes of EG described in humans and different livestock host reported in the literature.

Echinococcus granulosus (EG) es la principal causa de equinococosis quística en humanos y ganado en el mundo. En Chile hay una zoonosis de gran importancia. Las zonas geográficas más afectadas son las Regiones de Aysén, Los Ríos, Los Lagos, Coquimbo y la Araucanía. Por lo tanto, se descubrió que en áreas endémicas de hidatidosis podría haber varias cepas y genotipos de EG. Además, hay pruebas de que algunas cepas y genotipos son más infecciosos para los seres humanos que otros. Este interesante fenómeno de la biología del EG ha sido estudiado utilizando técnicas de biología molecular basadas en la reacción en cadena de la polimerasa (PCR) y análisis de secuencias de ADN, lo que ha permitido caracterizar el complejo de cestode llamado EG sensu lato (sl) EG (G3) y E. canadensis (G6-G10), que presentan una importante variación fenotípica detectable en las características del ciclo biológico, especificidad del huésped intermedio, patrón de desarrollo, patogenicidad, antigenicidad, dinámica de transmisión y, por consiguiente, en las medidas necesarias para el control de la enfermedad. El objetivo de este manuscrito fue describir los diferentes genotipos de EG descritos en humanos y diferentes animales de ganado reportados en la literatura.

Surgical and Molecular Evaluation of Pediatric Hydatid Cyst Cases in Eastern Turkey

Cystic echinococcosis (CE) caused by Echinococcus granulosus is a major public health problem worldwide, including Turkey. The aim of the current study was to identify the strains and to estimate the potential risk factors of E. granulosus in operated pediatric cases in eastern Turkey. Ten pediatric patients (7 boys and 3 girls) living in rural areas, with ages ranging from 3 to 15 years old and various clinical histories, were included in this study. Eight patients had only liver hydatid cyst, while 1 patient had liver and lung hydatid cyst and the other liver, lung, and spleen, together. There were 2 ruptured liver cysts. After surgery, during follow-up, no increase was observed in hemagglutination levels, there were no mortalities, and there was no evidence of recurrence at 2 years post operation in all patients. Molecular analysis was performed on hydatid cyst samples obtained from the 10 pediatric cases. According to mt-12S rRNA PCR results, all cases were found to be G1/G3 cluster of E. granulosus sensu stricto.

Serological and Molecular Characteristics of the First Korean Case of Echinococcus multilocularis

In December 2011, we reported an autochthonous case of Echinococcus multilocularis infection in a 42-year-old woman in Korea. The diagnosis was based on histopathological findings of the surgically resected liver cyst. In the present study, we evaluated the serological and molecular characteristics of this Korean E. multilocularis case. The patient's serum strongly reacted with affinity-purified native Em18 and recombinant Em18 antigens (specific for E. multilocularis) but negative for recombinant antigen B8/1 (reactive for Echinococcus granulosus). In immunoaffinity chromatography, the serum also strongly reacted with E. multilocularis and only weakly positive for E. granulosus. We determined the whole nucleotide sequence of cox1 (1,608 bp) using the paraffin-embedded cystic tissue which was compared with E. multilocularis isolates from China, Japan, Kazakhstan, Austria, France, and Slovakia. The Korean case showed 99.8-99.9% similarity with isolates from Asia (the highest similarity with an isolate from Sichuan, China), whereas the similarity with European isolates ranged from 99.5 to 99.6%.

Echinococcus granulosus genotypes circulating in alpacas (Lama pacos) and pigs (Sus scrofa) from an endemic region in Peru

The identification of the genotypes of Echinococcus granulosus present in livestock and wild animals within regions endemic for cystic echinococcosis (CE) is epidemiologically important. Individual strains display different biological characteristics that contribute to outbreaks of CE and that must be taken into account in the design of intervention programs. In this study, samples of hydatid cysts due to E. granulosus were collected from alpacas (4) in Puno and pigs (8) in Ayacucho in Peru, an endemic region for CE. Polymerase chain reaction amplification and DNA sequencing of specific regions of the mitochondrial cytochrome C oxidase subunit 1 and NADH dehydrogenase subunit 1 genes confirmed the presence of a strain common to sheep, the G1 genotype, in alpacas. Two different strains of E. granulosus were identified in pigs: the G1 and the G7 genotypes. This is the first report of the G1 genotype of E. granulosus in alpacas in endemic regions of CE in Peru.

Serological evaluation of EgAgB16 kDa, a recombinant antigen from echinococcus granulosus for diagnosis of human hydatidosis

Regarding that accurate diagnosis of human hydatidosis still needs more investigations, the present study was conducted to clone, express, and evaluate the gene encoding AgB subunits [EgAgB16 kDa] from Echinococcus granulosus [Iranian G1 strain] and its evaluation by ELISA test. DNA was extracted from protoscoleces and was utilized by PCR for strain identification. Total RNA was prepared with RNeasy protect mini kit from E. granulosus [Iranian G1 strain] protoscoleces collected from naturally infected sheep with hydatid cyst. Recombinant AgB16 kDa was produced using pETDuet as vector and evaluated by ELISA method. A panel of sera including hydatid cyst-infected individuals [n=72], healthy individual [n=48], toxoplasmosis [n=4], strongyloidosis [n=4], kala-azar [n=5] and tuberculosis [n=5] were examined using this recombinant antigen. Recombinant protein was purified by affinity chromatography using His-Tag column. After purification, recombinant protein was confirmed by western blot analysis using His Tag monoclonal anti body or hydatid positive human serum. The sensitivity, specificity; positive and negative predictive values were calculated as 93.5%, 95.6%, 96% and 92.9%, in that order. The cut-off point was detected 0.3 for rAgB16. While the produced recombinant AgB16 kDa showed promising results in diagnosing human hydatidosis, but more investigations should be implemented to reach an accurate gold standard

Echinococcus granulosus: biological comparison of cattle isolates from endemic regions of Argentina and Spain / Echinococcus granulosus: comparación biológica de aislados de bovinos de regiones endémicas de Argentina y España

In the present study we have compared cattle isolates of Echinococcus granulosus from Argentina and Spain. The aim was to compare and determine if there exist phenotypic and genetic differences within E. granulosus cattle isolates between an endemic area of Spain (where the disease is mainly restricted to a sheep-dog cycle) and an endemic area of Argentina (where cattle are the most abundant intermediate hosts). The Spanish samples were previously identified as G1 genotype. The Argentinean samples were also identified as G1, but some variants were found for the cytochrome c oxidase-1 (CO1) and NADH dehydrogenase-1 (ND1) mitochondrial genes. When comparing the cyst features and the morphology of the larval rostellar hooks in both regions, some differences were found. The morphometric analyses of the larval rostellar hooks showed the existence of two distinct clearly separated groups (one corresponding to the Argentinean samples and the other to the Spanish ones). In conclusion, there are some genetic and phenotypic differences within E. granulosus cattle isolates from Argentina and Spain. Probably these differences, more important from an epidemiological point of view, are related to different steps in the disease control in both countries. Further studies involving other epidemiological, morphometric and molecular data, including other types of livestock, would contribute to clarify and expand the present work.

El objetivo del presente trabajo fue determinar si existen diferencias fenotípicas y genéticas entre los aislados de Echinococcus granulosus de origen bovino provenientes de dos regiones geográficas donde la hidatidosis es endémica, una de España (donde predomina el ciclo perro-oveja) y una de Argentina (donde el bovino es el hospedador intermediario más importante). Las muestras españolas fueron previamente identificadas como pertenecientes al genotipo G1. Las muestras argentinas también correspondían al genotipo G1, pero entre ellas se registraron algunas microvariantes de los genes mitocondriales citocromo c oxidasa-1 (CO1) y NADH deshidrogenasa- 1 (ND1). La comparación de las características de los quistes y de la morfología de los ganchos rostelares del metacestode mostró ciertas diferencias. En conclusión, existen algunas diferencias genéticas y fenotípicas entre los aislados de E. granulosus de Argentina y España. Probablemente estas diferencias, más importantes desde el punto de vista epidemiológico, podrían estar relacionadas con diferentes etapas en los programas de control de la enfermedad en los dos países. Estudios adicionales que involucren datos epidemiológicos, morfométricos y moleculares provenientes de otros tipos de ganado contribuirán a clarificar y ampliar la información aportada por este trabajo.

Genetic Variability of Antigen B among Echinococcus granulosus Egyptian Isolates

Genetic polymorphisms of encoding antigen B2 gene (AgB2) in Echinococcus granulosus were studied using PCR-RFLP and DNA sequencing among 20 Egyptian isolates. Five isolates from different host origins (humans, camels, pigs, and sheep) were collected and used. All examined isolates of each host group gave very similar patterns of PCR-RFLP after restriction enzyme digestion with AluI, with the gene size of approximately 140 bp and 240 bp for sheep and human isolates, and approximately 150 bp and 250 bp for pig and camel isolates. No digestion pattern was obtained after incubation of all studied isolates with EcoRI. These results reveal high intra-group homogeneity. DNA sequence analysis highlighted that human infecting strain showed 100% identity with respect to sheep infecting isolate, 96% and 99% with pig and camel infecting isolates, respectively.

Molecular appraisal of Indian animal isolates of Echinococcus granulosus.

BACKGROUND & OBJECTIVE: Cystic echinococcosis (CE) has a wide host range and distinct entities, not only reflected phenotypically but also by genotypic variation. Considering this fact, this study was undertaken to characterize the Indian isolates of Echinococcus granulosus to find out difference between Indian cattle, buffalo and sheep isolates on the basis of random amplification of polymorphic DNA (RAPD) PCR and PCR mediated restriction fragment length polymorphism (PCRRFLP) of internal transcribed spacer gene 1 (ITS1). METHODS: A total of 22 isolates of E. granulosus obtained from Indian cattle, buffalo and sheep (December 2004 - November 2005) were analysed by 26 random primers of 8-10 mers. After isolation of protoscoleces from fertile cyst, DNA was extracted, quantified and amplified by random primers. Internal transcribed spacer gene 1 (ITS1) was amplified using specific primer and digested by two restriction enzymes (Msp1 and Rsa1). RESULTS: Of the 26 primers, only two primers (5'ACC TGG ACA C3' and 5' TCA TCC GAG G3') could discriminate cattle, buffalo and sheep isolates collected from eastern part of India. Samples were further analysed by PCR mediated RFLP of internal transcribed spacer gene1 (ITS1) using two restriction enzymes (Msp1 and Rsa1). No ITS1 variants could be detected. INTERPRETATION & CONCLUSION: Our findings showed genotypic variation among Indian animal isolates of E. granulosus on the basis of RAPD fingerprinting.

New data on Echinococcus spp. in Southern Brazil

Quarenta isolados de Echinococcus provenientes de ovinos e bovinos do sul do Brasil foram analisados geneticamente com o objetivo de obter dados a respeito das diferentes cepas dentro do gênero Echinococcus granulosus. A diferenciação foi feita empregando-se a técnica de PCR a o seqüenciamento da subunidade 1 da citocromo c oxidase (CO1). A maior parte das amostras (38) pôde ser alocada na cepa ovina (G1) enquanto duas amostras pertenceram ao gênero E. ortleppi, anteriormente conhecido como cepa bovina (G5) do E. granulosus. Devido ao menor período pré-patente em cães deste último gênero ressalta-se a importância do presente registro devido às implicações no delineamento de medidas de controle nesta região endêmica.

Detection of genetic polymorphism among and within Echinococcus granulosus strains by heteroduplex analysis of a microsatellite from the U1 snRNA genes

Polymerase chain reaction of a pentanucleotide microsatellite in the U1 snRNA gene complex generated a multiple band pattern due to the priming of paralogous sequences. Denaturation and slow renaturation of polymerase chain reaction products allow the formation of heteroduplex DNA that can be detected by its differential mobility in polyacrylamide gel electrophoresis. Heteroduplex analysis was used to determine if the U1 snRNA microsatellite could be a useful genetic marker in Echinococcus granulosus. A U1 snRNA microsatellite fragment from E. granulosus was isolated and characterized by Southern blot and sequencing. Four E. granulosus strains were analyzed: sheep, Tasmanian sheep, cattle, and camel strains. The former two showed polymorphism and shared three of the six patterns found for sheep strain. The cattle strain displayed two patterns, and the camel strain was monomorphic. The electrophoretic profiles were used for statistical analysis in order to determine genetic distance and the relationship among strains. Heteroduplex analysis can be helpful in genotyping E. granulosus strains and is useful in detecting polymorphism within strains.