Detection of antigens in paraffin sections of worms and snails infected by Angiostrongylus cantonensis by immunofluorescence reaction / Detecção de antígenos em cortes parafinados de vermes e caramujos infectados por Angiostrongylus cantonensis pela reação de imunofluorescência

The Indirect Immunofluorescence Assay (IFA) was used to identify stage-specific antigenic structures in paraffin sections of female larvae and worms and snails tissues, infected with third stage larvae of Angiostrongylus cantonensis. Sera from eosinophilic meningitis cases were used to assess reactivity. Non-reactive sera from patients with other parasitic diseases and from individuals without other etiologies were used as controls for cross-reactivity. Larvae and worms showed high reactivity to IgG antibodies. IgM antibodies reacted with low intensity only to larvae. Fluorescent reactions were observed in the cuticles and internal structures on worms sections, with a marked reaction in the uterus content. In the snail tissues, the larvae were found exclusively inside the granulomas, with fluorescent markings in the cuticles of the larvae and inside the granulomatous tissues. This fluorescent pattern suggests the presence of excretory/secretory antigens distributed throughout the granulomas. Expressive cross-reactivity occurred in sera from patients with other parasitic diseases, especially strongyloidiasis. The use of IFA applied to paraffin sections to identify structures with antigenic potential and the study of new serological markers, can contribute to the improvement of the laboratory diagnosis of eosinophilic meningitis. (AU)

A Reação de Imunofluorescência Indireta (RIFI) foi utilizada para localizar antígenos em estruturas estágio-específicas em cortes parafinados de vermes fêmeas e em tecidos de caramujos do Gênero Biomphalaria infectados com larvas de terceiro estágio de Angiostrongylus cantonensis. Soros de casos confirmados de meningite eosinfílica foram usados para avaliação da reatividade. Soros não reagentes de casos suspeitos; de pacientes com outras parasitoses e de indivíduos sem outras etiologias foram utilizados como controle de reatividade cruzada. Anticorpos da classe IgG foram reativos para antígenos presentes nos dois estágios e, anticorpos IgM somente para o estágio larvário. Nos cortes de vermes, as marcações fluorescentes foram assinaladas nas cutículas e estruturas internas, com acentuada marcação para os conteúdos uterinos. Nos tecidos dos caramujos as larvas foram encontradas exclusivamente no interior dos granulomas, com marcações fluorescentes nas cutículas das larvas e no interior dos tecidos granulomatosos. O padrão de fluorescência no granuloma sugere a marcação de antígenos excretores/secretores. Reatividade cruzada mais expressiva ocorreu com anticorpos presentes em soros de pacientes com outras parasitoses, com destaque para estrongiloidíase. A RIFI em cortes parafinados abre novas perspectivas para identificação de antígenos e de marcadores sorológicos, que possam ser aplicados no aprimoramento do diagnóstico laboratorial da meningite eosinofílica. (AU)

Angiostrongylus cantonensis en Achatina fulica en la provincia del Napo, Ecuador y el riesgo incrementado de angiostrongiliasis / Angiostrongylus cantonensis in Achatina fulica in Napo province, Ecuador and the increased risk of angiostrongyliasis

Introducción: Angiostrongylus cantonensis es reconocido como uno de los principales patógenos causantes de la meningoencefalitis eosinofílica, fue identificado en Ecuador por primera vez en 2008. Métodos: se recolectaron 1476 ejemplares de Achatina fulica con el método de captura por unidad de esfuerzo durante 30 minutos, en 3 cantones de la provincia del Napo, con el fin de establecer la prevalencia de infección por A. cantonensis Resultados: el porcentaje total de caracoles infectados fue de 46,5% (687/1476). Conclusiones: Los resultados revelan una amplia distribución de A. fulica infectado con A. cantonensis, lo que, sumado a la gran cantidad de hospederos definitivos presentes, indica que un número considerable de personas tiene riesgo de adquirir angiostrongiliasis. Se necesita intervenciones educativas comunitaria orientadas a formación sanitaria, recalcando el riesgo de adquirir la infección parasitaria, principalmente por el consumo de A. fulica, crudos y/o con cocción inadecuada, principal forma de contagio. Además, se recomienda vigilancia rigurosa y control de los hospedadores involucrados, saneamiento ambiental, haciendo insistencia en factores relacionados con los hábitos biológico del caracol gigante africano, entre ello alimentos (vegetales), suelos y derivados del caracol de uso artesanal; para prevenir la aparición de casos esporádicos y de brotes de la enfermedad(AU)

Introduction: Angiostrongylus cantonensis is recognized as one of the main pathogens that cause eosinophilic meningoencephalitis, it was identified in Ecuador for the first time in 2008. Methods: 1476 specimens of Achatina fulica were collected using the capture method per unit of effort for 30 minutes, in 3 cantons of the Napo province, in order to establish the prevalence of infection by A. cantonensis Results: the total percentage of infected snails was 46.5% (687/1476). Conclusions: The results reveal a wide distribution of A. fulica infected with A. cantonensis, which, added to the large number of definitive hosts present, indicates that a considerable number of people are at risk of acquiring angiostrongyliasis. Community educational interventions aimed at health training are needed, emphasizing the risk of acquiring parasitic infection, mainly due to the consumption of A. fulica, raw and/or inadequately cooked, the main form of contagion. In addition, rigorous surveillance and control of the hosts involved, environmental sanitation, insisting on factors related to the biological habits of the giant African snail, including food (vegetables), soil and snail derivatives for artisanal use; to prevent the appearance of sporadic cases and outbreaks of the disease(AU)

Particularidades de la meningoencefalitis eosinofílica en la era del caracol gigante africano / Particular features of eosinophilic meningoencephalitis in the age of the giant African snail

Introducción: la meningoencefalitis eosinofílica es una enfermedad inflamatoria infecciosa reportada en Cuba desde la década de los ochenta del siglo pasado y actualmente extendida al continente americano. Es producida por el parásito Angiostrongylus cantonensis. Objetivo: determinar si existen diferencias entre los pacientes que sufrieron meningoencefalitis eosinofílica antes y después de la introducción del caracol gigante africano. Métodos: se estudiaron un total de 19 muestras de líquido cefalorraquídeo y suero tomadas simultáneamente a cada paciente diagnosticados con meningoencefalitis eosinofílica, perteneciente a la seroraquioteca del Laboratorio Central del Líquido Cefalorraquídeo (LABCEL). Para la determinación de las proteínas albúmina e IgG se empleó como método de laboratorio la inmunodifusión radial. Resultados: el 14 por ciento de los pacientes fueron adultos antes de la aparición de este molusco, en contraste con el momento actual, donde el 50 por ciento son pacientes con edades superiores a 18 años. El porcentaje de síntesis de IgG intratecal media fue mayor en los enfermos actuales, aunque no de manera significativa. Conclusiones: . existen diferencias antes y después de la aparición del caracol gigante africano dado por la respuesta de síntesis intratecal en los pacientes asociados con el molusco que denota una mayor agresividad del parásito. La edad promedio mayor de los enfermos confirma que estos son los que más manipulan y dispersan el molusco(AU)

Introduction: eosinophilic meningoencephalitis is an infectious inflammatory disease reported in Cuba since the 1980s and currently extended to the American continent. This condition is caused by the parasite Angiostrongylus cantonensis. Objective: determine whether there are differences between the patients suffering from eosinophilic meningoencephalitis before and after the introduction of the giant African snail. Methods: a study was conducted of a total 19 cerebrospinal fluid and serum samples taken simultaneously from each of the patients diagnosed with eosinophilic meningoencephalitis and kept at the sample collection of the Central Cerebrospinal Fluid Laboratory (LABCEL). Radial immunodiffusion was the laboratory method used for determination of the proteins albumin and IgG. Results: of the patients studied, 14 percent were adults before the appearance of this mollusc, in contrast with the present moment, when 50 percent are patients aged over 18 years. The percentage of mean intrathecal synthesis of IgG was higher in the current sufferers, though not significantly. Conclusions: there are differences before and after the appearance of the giant African snail, given the intrathecal synthesis response of patients associated to the mollusc, which denotes greater aggressiveness by the parasite. The higher mean age of sufferers confirms that these are the ones who most often handle and disperse the mollusc(AU)

El riesgo de parasitismo por Angiostrongylus cantonensis: una problemática reemergente en Cuba / The risk of parasitism by Angiostrongylus cantonensis: a re-emerging problem in Cuba / O risco de parasitismo devido a Angiostrongylus cantonensis: um problema reemergente em Cuba

RESUMEN Introducción: El riesgo de parasitismo por Angiostrongylus cantonensis transmitido por el caracol gigante africano es una problemática reemergente en Cuba. Objetivo: Sistematizar contenidos esenciales relacionados con el caracol gigante africano y el parásito Angiostrongylus cantonensis, el riesgo de meningitis eosinofílica y su manejo. Método: En el Hospital General Docente "Dr. Agostinho Neto", entre septiembre y diciembre de 2019 se hizo una revisión narrativa sobre el tema a través de una búsqueda en bases de datos electrónicas (Biblioteca Virtual en Salud): LILACS, PubMed, SciELO, RedALyC, Scopus, Cochrane. Resultados: La información se estructuró en caracterización del caracol gigante africano y el riesgo de infección por Angiostrongylus cantonensis en Cuba, patogénesis y epidemiologia de la angiostrongylosis, y diagnóstico y tratamiento de la meningitis eosinofílica por este nemátodo. Se identificaron controversias sobre los criterios diagnósticos, el protocolo de actuación para su prevención y rehabilitación, y la carencia de un instrumento para estratificar el riesgo de esta infección. Conclusiones: Se sistematizaron contenidos esenciales sobre el caracol gigante africano, lo que posibilita la preparación de los profesionales para incrementar la percepción del riesgo de infección por Angiostrongylus cantonensis en la población.

ABSTRACT Introduction: The risk of parasitism by Angiostrongylus cantonensis transmitted by the giant African land snail, Lissachatina fulica is a re-emerging problem in Cuba. Objective: Systematize essential contents related to the giant African land snail and the parasite Angiostrongylus cantonensis, the risk of eosinophilic meningitis and its management. Method: A narrative review was made on the subject in the Teaching General Hospital "Dr. Agostinho Neto", between September and December 2019 through a search in electronic databases (Virtual Health Library): LILACS, PubMed, SciELO, RedALyC, Scopus, Cochrane. Results: The information was structured in the characterization of the African giant land snail and the risk of infection by Angiostrongylus cantonensis in Cuba, pathogenesis and epidemiology of angiostrongylosis, and diagnosis and treatment of eosinophilic meningitis by this nematode. Controversies were identified regarding the diagnostic criteria, the protocol of action for its prevention and rehabilitation, and the lack of an instrument to stratify the risk of this infection. Conclusions: Essential content on the giant African land snail was systematized, enabling the preparation of professionals to increase the perception of the risk of infection by Angiostrongylus cantonensis in the population.

RESUMO Introdução: O risco de parasitismo causado por Angiostrongylus cantonensis transmitido pelo caracol gigante africano é um problema reemergente em Cuba. Objetivo: Sistematizar conteúdos essenciais relacionados ao caracol gigante africano e ao parasita Angiostrongylus cantonensis, ao risco de meningite eosinofílica e seu manejo. Método: No Hospital Geral de Ensino "Dr. Agostinho Neto", entre setembro e dezembro de 2019, foi realizada uma revisão narrativa do assunto através de uma busca em bases de dados eletrônicas (Biblioteca Virtual em Saúde): LILACS, PubMed, SciELO, RedALyC, Scopus, Cochrane. Resultados: As informações foram estruturadas na caracterização do caracol gigante africano e no risco de infecção por Angiostrongylus cantonensis em Cuba, patogênese e epidemiologia da angiostrongilose, diagnóstico e tratamento da meningite eosinofílica por esse nematóide. Foram identificadas controvérsias sobre os critérios diagnósticos, o protocolo de ação para sua prevenção e reabilitação e a falta de um instrumento para estratificar o risco dessa infecção. Conclusões: Foram sistematizados conteúdos essenciais sobre o caracol gigante africano, o que possibilita a preparação de profissionais para aumentar a percepção do risco de infecção por Angiostrongylus cantonensis na população.

Evidencias clínico-epidemiológicas vinculadas a Lissachatina fulica en un adulto con meningoencefalitis eosinofílica causada por Angiostrongylus cantonensis / Clinical-epidemiological evidence related to Lissachatina fulica in an adult with eosinophilic meningoencephalitis caused by Angiostrongylus cantonensis

Introducción: El helminto Angiostrongylus cantonensis es un parásito habitual en los pulmones de la rata y puede ocasionar meningoencefalitis eosinofílica en el hombre cuando se pone en contacto con las larvas por ingestión accidental. En Cuba es endémico y el riesgo de contraerlo aumenta con la entrada del caracol gigante africano en el país. Objetivo: Describir las acciones desarrolladas por las autoridades sanitarias locales para el control del caracol gigante africano entre 2016 y 2018 y la aparición de un paciente en 2018 con meningoencefalitis eosinofílica causada por Angiostrongylus cantonensis vinculado epidemiológicamente con la presencia de este caracol. Métodos: Se realizó un estudio cualitativo a partir de un grupo focal con el que se trabajó ante la aparición del caracol gigante africano en un área de salud del municipio San Miguel del Padrón. Se realiza una encuesta semi-estructurada. Resultados: Se trazaron las estrategias para la erradicación de la especie invasora a partir de un trabajo comunitario. Dos años después, se observa nuevamente el caracol gigante africano y un paciente con meningoencefalitis eosinofílica epidemiológicamente asociado a Angiostrongylus cantonensis. Conclusiones: Las acciones realizadas entre 2016 y 2018 resultaron ser insuficientes por el nuevo avistamiento del caracol en el área, con el agravante de encontrar un paciente con meningoencefalitis eosinofílica epidemiológicamente asociado con el molusco(AU)

Introduction: Helmint Angiostrongylus cantonensis is a natural parasite in the lungs of ratas. Ocassionally it can produced an eosinophilic meningoencephalitis in men by larvae accidental ingestion. Methods: A qualitative study was performed from a focal group by a semi-structural survey in a health area from San Miguel del Padrón municipality. Objectives: To describe the actions developed by the local sanitarian authorities for the control of African giant snails between 2016 and 2018 and the appearance of a patient suffering from eosinophilic meningoencephalitis due to Angiostrongylus cantonensis linked to the presence of this snail. Results: It has been established an eradication strategy for the elimination of this invasive species based on a community work. Two years later, it was observed again the giant African snail in the area with a patient suffering from Angiostrongylus cantonensis eosinophilic meningoencephalitis epidemiologically associated. Conclusions: The 2016 actions were not efficient due to the emerging vector and the further finding of a patient linked with the parasite(AU)

Prevalence of Angiostrongylus cantonensis and Angiostrongylus costaricensis in Achatina fulica snails in the municipality of São Bernardo do Campo (SP, Brazil) / Prevalência de Angiostrongylus cantonensis e Angiostrongylus costaricensis em caramujos Achatina fulica na cidade de São Bernardo do Campo (SP, Brasil)

Angiostrongylus cantonensis e Angiostrongylus costaricensis são nematoides parasitas que residem em roedores e usam gastrópodes como hospedeiros intermediários. Achatina fulica, conhecida como caramujo-gigante-africano, é um hospedeiro intermediário que desempenha importante papel na dispersão de A. cantonensis e A. costaricensis, patógenos zoonóticos que causam, respectivamente, meningoencefalite eosinofílica e angiostrongilíase abdominal em humanos. O objetivo deste estudo foi o de coletar caramujos (A. fulica, n=90) de oito regiões diferentes (Rudge Ramos, Baeta Neves, Planalto, Demarchi, Dos Alvarengas, Batistini, Montanhão, Rio Grande) da cidade de São Bernardo do Campo (SP) para detecção molecular de A. cantonensis ou A. costaricensis pela técnica de reação em cadeia da polimerase (PCR). As amostras foram processadas em pools (n=25) segundo a região de coleta. Com exceção da região de Baeta Neves, as demais apresentaram caramujos infectados com larvas de nematoides. Seis regiões apresentaram amostras positivas para A. cantonensis. Quatorze (56%) das 25 amostras em pool apresentaram larvas de nematoides, e 52% delas (13/25) foram positivas para A. cantonensis. Nenhuma amostra positiva para A. costaricensis foi encontrada. A presença de A. fulica naturalmente infectada por A. cantonensis deve servir como um alerta para as autoridades de saúde pública sobre o risco potencial de infecção para humanos.(AU)

Gastropods as intermediate hosts of Angiostrongylus spp. in the Americas: bioecological characteristics and geographical distribution

BACKGROUND Intermediate hosts are key organisms in maintaining parasite life cycles, because they can act as amplifiers in the transmission from natural reservoirs to humans. One of the most important groups of intermediate hosts for zoonotic nematode infections are gastropods,slugs and snails. These are essential organisms in the larval development of Angiostrongylus species. OBJECTIVES The objective of this paper is to review reports of Angiostrongylus spp. in naturally infected gastropods from the Americas, taking into account the diagnostic methods used in their identification, to be able to provide more accurate list of their intermediate hosts. We also discuss the factors that aid the dispersion of Angiostrongylus spp. in the Americas. METHODS This study reviews scientific publications and book sections on Angiostrongylus spp. in the Americas, including original works assessing larvae of Angiostrongylus in intermediate hosts. The eligible reports were classified accordingly to their geographical location, year of first record, and the larvae identification methodologies used. Digital repositories were used for the search. The bioecological characteristics of the main intermediate hosts are summarised. FINDINGS A total of 29 gastropod species that are naturally infected with Angiostrongylus spp. have been reported as intermediate hosts, 16 of which are land snails, two are freshwater snails, and 11 land slugs. MAIN CONCLUSIONS This study highlights the importance of integrative studies, analysing both the etiological agent and its transmission dynamic in the environment, the biological and ecological characteristics of the hosts, and the impact on host populations. It is necessary to increase interdisciplinary studies to determine the potential epidemiological health risk of angiostrongyliasis in the Americas, and thus be able to establish prevention, monitoring and contingency strategies in the region.

Aprimoramento do imunodiagnóstico da angiostrongilíase meningoencefálica frente a diferentes preparações antigênicas de Angiostrongylus cantonensis / Improved immunodiagnosis of meningoencephalic angiostrongyliasis against different antigenic preparations of Angiostrongylus cantonensis

Angiostrongylus cantonensis é o agente etiológico da neuroangiostrongilíase, o qual se desenvolve em diversas espécies de moluscos e atinge a fase adulta em vertebrados, principalmente roedores, com a possibilidade de participação de hospedeiros paratênicos. A transmissão humana ocorre por meio da preparação inadequada e consumo de moluscos ou hospedeiros de transporte infectados, onde a migração de larvas L3 para o sistema nervoso central causa o quadro de meningite eosinofílica. O diagnóstico laboratorial da patologia é baseado em testes moleculares, que podem apresentar baixa sensibilidade em regiões não endêmicas, e imunológicos utilizando antígenos brutos de fêmeas jovens e adultas, com sensibilidades e especificidades variadas. O objetivo deste trabalho foi estudar diferentes preparações antigênicas de fases evolutivas distintas de A. cantonensis, com o intuito de aperfeiçoar as técnicas sorológicas para o imunodiagnóstico da doença. Para tanto, fêmeas adultas foram avaliadas pela reação de imunofluorescência indireta em cortes parafinados para a focalização de regiões antigênicas no corpo do parasita. Além disso, frações antigênicas de diferentes formas evolutivas foram avaliadas pelas técnicas Dot-ELISA e Western blot com soros e LCRs. Os resultados apontam para a presença de proteínas antigênicas no sistema reprodutivo de fêmeas, além da possibilidade de melhoria do diagnóstico com a utilização de antígenos brutos de fêmeas em associação com antígenos alcalinos de membrana extraídos de vermes adultos para auxiliar no diagnóstico e desencadear ações de vigilância e controle da angiostrongilíase meningoencefálica.

Infection by Angiostrongylus cantonensis in both humans and the snail Achatina (Lissachatina) fulica in the city of Macapá, in the Amazon Region of Brazil

In January and February 2019, a malacological survey was conducted in the area surrounding the residence of a 12-year-old child that had contracted cerebral angiostrongyliasis in the municipality of Macapá, capital of the Amapá State, northern Brazil. The serological examination was positive for Angiostrongylus cantonensis infection, the principal etiological agent of this parasitosis. A sample of 54 molluscs was artificially and individually digested for parasitological analysis, containing 38 specimens of Achatina fulica, nine specimens of Bulimulus tenuissimus and seven specimens of Sarasinula linguaeformis. A. fulica was the most abundant mollusc, and the only species infected with A. cantonensis, as well as presenting co-infections with other nematodes. This is the first report of cerebral angiostrongyliasis in the Amazon Region, and the first record of A. fulica infected with A. cantonensis in Amapá. These findings highlight the potential risks of human angiostrongyliasis, and the need to implement public health measures to control the spread of the disease.

Abdominal angiostrongyliasis can be diagnosed with a immunochromatographic rapid test with recombinant galactin from Angiostrongylus cantonensis

Angiostrongylus costaricensis is the causative agent of abdominal angiostrongyliasis, a zoonotic infection that may produce severe eosinophilic enterocolitis or hepatitis in humans. Parasites are usually not released in stools and serology has an important role in diagnosis. Since cross-reactivity is demonstrated between A. costaricensis and another metastrongylid worm, A. cantonensis, we tested heterologous recombinant galectin as a probe in an immunochromatographic rapid diagnostic test (ICT-RDT) for detection of anti-A. costaricensis antibodies. Almost all (11/12) positive control sera from A. costaricensis infected patients were positive at ICT RDT. These are preliminary indications that r-galectin ICT-RDT is useful for diagnosing A. costaricensis infection.

Diagnóstico neuroinmunológico de meningoencefalitis eosinofílica producida por Angiostrongylus cantonensis / Neuroimmunological diagnosis of eosinophilic meningoencephalitis caused by Angiostrongylus cantonensis

El diagnóstico de la meningoencefalitis por Angiostrongylus cantonensis se establece por la presencia de las larvas del helminto en el líquido cefalorraquídeo, pero esta evidencia es muy difícil de encontrar ya que las larvas son lábiles en este medio y no se hallan con frecuencia. Debido a que en Cuba, la presencia del parásito se remonta a 1981 y este parásito es el único que puede provocar esta enfermedad en el país, se realiza una revisión con el objetivo de revisar la literatura publicada sobre el tema para acopiar toda la evidencia que ayude al diagnóstico auxiliar de meningoencefalitis eosinofílica. Se propone que el estudio de la síntesis intratecal de IgE y C3c, unido al patrón de síntesis local de IgA+IgG principalmente y de IgG1+ IgG2 resultan las más indicadas. Existen otras proteínas que pudieran auxiliar como la síntesis intratecal de C4 y en menor proporción MBL(AU)

Diagnosis of meningoencephalitis due to Angiostrongylus cantonensis is based on the presence of helminth larvae in cerebrospinal fluid, but such evidence is very hard to find, since the larvae are labile in this medium and cannot be spotted easily. Based on the fact that presence of the parasite in Cuba dates back to 1981, and this is the only agent of the disease in the country, a review was conducted with the purpose of going over the published literature about the topic and gather evidence leading to the auxiliary diagnosis of eosinophilic meningoencephalitis. The study of the intrathecal synthesis of IgE and C3c, alongside the local synthesis pattern for IgA+IgG mainly and IgG1+IgG2, are proposed as the most appropriate. Other useful proteins are the intrathecal synthesis of C4 and to a lesser extent MBL(AU)

Strongylides in Achatina(Lissachatina)fulica (Mollusca, Achatinidae) in Havana, Cuba / Strongylides in Achatina(Lissachatina)fulica (Mollusca, Achatinidae) in Havana, Cuba

ABSTRACT Achatina (Lissachatina) fulica was introduced in Cuba in 2014 for african religious purposes and nowadays, mainly by human activity, it is widespread all over the country and, where besides a general nuisance for people it is a pest and also a public health concern, since it is one of the natural intermediate host of Angiostrongylus cantonensis, ethiological agent of the meningoencephalitis. As in Havana is experiencing the explosive phase of the invasion, LABCEL has been receiving samples of these molluscs for identification and search for Angiostrongylus cantonensis larvae. While examining samples of A. fulica different larvae were obtained, as strongylides found in the interior of the pallial cavity of A. fulica.This is the first report in San Miguel del Padron and Regla municipalities of the development of larvae in A. Fulica evidencing the health importance of this mollusc in the potential transmission of eosinophilic meningoencephalitis. Since the spread of A. fulica is pointed out in the literature as one of the main causative spread of the meningoencephalitis caused by A. cantonensis the authors emphasize the need of sanitary vigilance of snails and rats from vulnerable areas for A. cantonensis introduction as the port side areas like these municipalities.

RESUMEN Achatina (Lissachatina) fulica se introdujo en Cuba en 2014 con fines religiosos africanos y hoy en día, principalmente por actividad humana, está muy extendida en todo el país y, además de una molestia general para las personas, es una plaga y también un problema de salud pública, ya que es uno de los huéspedes intermedios naturales de Angiostrongylus cantonensis, agente etiológico de la meningoencefalitis. Como en La Habana está experimentando la fase explosiva de la invasión, LABCEL ha estado recibiendo muestras de estos moluscos para su identificación y búsqueda de larvas de Angiostrongylus cantonensis. Mientras se examinaban muestras de A. fulica, se obtuvieron diferentes larvas, como strongylides encontrados en el interior de la cavidad paliar de A. fulica. Este es el primer informe en los municipios de San Miguel del Padrón y Regla sobre el desarrollo de larvas en A. Fulica evidenciando La importancia para la salud de este molusco en la transmisión potencial de la meningoencefalitis eosinofílica. Dado que la propagación de A. fulica se señala en la literatura como una de las principales causas de la meningoencefalitis causada por A. cantonensis, los autores enfatizan la necesidad de vigilancia sanitaria de caracoles y ratas de áreas vulnerables para la introducción de A. cantonensis como zonas de babor como estos municipios.

First record of Bulimulus tenuissimus (Mollusca) as potential experimental intermediate host of Angiostrongylus cantonensis (Nematoda) / Primeiro registro de Bulimulus tenuissimus (Mollusca) como hospedeiro intermediário de Angiostrongylus cantonensis (Nematoda)

Abstract Snails are essential to complete the life cycle of the metastrongylid nematode Angiostrongylus cantonensis, the causative agent of infections in domestic and wild animals, mainly rodents, and also of neural angiostrongyliasis or eosinophilic meningitis in humans. There are many reports of mollusks that can act as intermediate hosts of this parasite, especially freshwater snails and the African giant Achatina fulica. The terrestrial gastropod Bulimulus tenuissimus is widely distributed in Brazil and other species of the same genus occur in Brazil and other countries, overlapping regions in which there are reports of the occurrence of A. cantonensis and angiostrongyliasis. In spite of this, there are no records in the literature of this species performing the role of intermediate host to A. cantonensis. The present study analyzed the experimental infection with first-stage larvae of A. cantonensis, under laboratory conditions, of B. tenuissimus, by using histology and electron microscopy techniques. Three weeks after exposure to L1 larvae, it was possible to recover L3 larvae in small numbers from the infected snails. Developing larvae were observed in the cephalopedal mass (foot), ovotestis, and mantle tissues, being located inside a granulomatous structure composed of hemocyte infiltration, but there was no calcium or collagen deposition in these structures in significant amounts. In the third week post exposure, it was possible observe a sheath around the developing larvae. The infected snails presented reduction in the fibrous muscular tissue in the foot region, loss of the acinar organization in the digestive gland, with increase of amorphous material inside the acini and loss of epithelial pattern of nuclear organization in the acinar cells. However, the ovotestis seemed unaffected by the infection, since there was a large number of developing oocytes and spermatozoa in different stages of formation. The digestion of infected snails allows us the third-stage recovery rate of 17.25%, at 14 days post exposure to the L1. These L3 recovered from B. tenuissimus were used to infect rats experimentally, and 43 days post infection first-stage (L1) larvae of A. cantonensis were recovered from fresh feces. The results presented constituted the first report of the role of B. tenuissimus as an experimental intermediate host to A. cantonensis and shed some light on a possible problem, since the overlapping distribution of B. tenuissimus and A. cantonensis in Brazil and other countries where different species of Bulimulus occur enables the establishment and maintenance of the life cycle of this parasite in nature, with wild rodents as reservoirs, acting as a source of infection to humans, causing neural angiostrongyliasis.

Resumo Os moluscos são um requisito essencial para a conclusão do ciclo de vida pelo nematoide metastrogilídeo Angiostrongylus cantonensis, o agente causador de infecções em animais domésticos e selvagens, principalmente roedores, e também de angiostrongilíase neural ou meningite eosinofílica em humanos. Há muitos relatos de moluscos que podem atuar como hospedeiro para este parasito, sendo o foco dado aos moluscos de água doce e no gigante africano Achatina fulica. O gastrópode terrestre Bulimulus tenuissimus é amplamente distribuído no território brasileiro e há outras espécies do mesmo gênero que ocorrem no Brasil e outros países, sobrepondo-se às regiões em que há relatos à ocorrência de A. cantonensis e angiostornigilíase. Apesar disso, não há registro na literatura, acerca desta espécie como hospedeiro intermediário para A. cantonensis. O presente estudo teve como objetivo verificar a possibilidade de infectar experimentalmente, utilizando larvas L1 de A. cantonensis, em condições laboratoriais, o molusco B. tenuissimus, utilizando técnicas de histologia e microscopia eletrônica. Três semanas após a exposição às larvas L1, foi possível recuperar larvas L3 dos moluscos infectados, em pequena quantidade. As larvas em desenvolvimento foram observadas na massa cefalopediosa (pé), ovotestis e nos tecidos do manto, sendo localizadas dentro de uma estrutura granulomatosa constituída por infiltração hemocitária, mas não houve deposição de cálcio ou colágeno nessas estruturas em quantidade significativa. Na terceira semana pós exposição, foi possível observar uma bainha ao redor das larvas em desenvolvimento. Os caracóis infectados apresentaram redução no tecido muscular fibroso na região do pé, perda da organização acinar na glândula digestiva, com aumento de material amorfo dentro dos ácinos e perda do padrão epitelial da organização nuclear nas células acinares. No entanto, o ovotestis, pareceu não ser afetado pela infecção, uma vez que houve um grande número de oócitos em desenvolvimento e espermatozóides em diferentes estágios de formação. A digestão dos moluscos infectados nos permitiu a recuperação de larvas de terceiro estágio (17,25%), aos 14 dias após a exposição à L1 de A. cantonensis . Estas L3 recuperadas de B. tenuissimus foram utilizados para infectar ratos experimentalmente, e 43 dias após a infecção, as larvas do primeiro estágio (L1) foram recuperadas de fezes frescas. Os resultados apresentados representam o primeiro registro do papel de B. tenuissimus como hospedeiro intermediário experimental de A. cantonensis e trazem alguma luz a um problema, até então silencioso, uma vez que a sobreposição da distribuição de B. tenuissimus e A. cantonensis no Brasil, e outros países, onde as diferentes espécies de Bulimulus ocorrem, torna possível o estabelecimento e manutenção do ciclo de vida deste parasito na natureza, com roedores selvagens como reservatório, agindo como fonte de infecção para humanos e causando a angiostrongilíase neural.

Confirmation of the presence of Angiostrongylus cantonensis in lung tissue of the African giant snail (Lissachatina fulica) in Colombia / Confirmación de la presencia de Angiostrongylus cantonensis en tejido pulmonar de caracol gigante Africano (Lissachatina fulica) en Colombia

Objetive: To confirm the presence of Angiostrongylus cantonensis in Lissachatina fulica individuals in Colombia. Methods: 19 individuals of L. fulica were collected in the city of Buenaventura, Valle del Cauca, Colombia. Lung tissue was extracted and two analysis methods were used: visual identification by histological observation, and identification through conventional and real-time PCR. The A. cantonensis detection rate was established taking into account each of the analysis techniques used. Results: Presence of A. cantonensis was confirmed in the lung tissue of L. fulica specimens collected in the city of Buenaventura, Valle del Cauca, Colombia. The detection rate based on visual identification through histological analysis was 89%, whereas it was 95% using conventional PCR, and 100% using real-time PCR. Conclusion: This study confirmed for the first time the presence of A. cantonensis associated with L. fulica specimens in Colombia. Therefore, eosinophilic meningitis could be considered an emerging disease in Colombia.

Objetivo: confirmar la presencia de Angiostrongylus cantonensis en individuos de Lissachatina fulica en Colombia. Materiales y métodos: se recolectaron 19 individuos de L. fulica en la ciudad de Buenaventura, Valle del Cauca, Colombia. Se extrajo el tejido pumonar y se utilizaron dos métodos de análisis: identificación visual por observación histológica e identificación a través de PCR convencional y en tiempo real. La tasa de detección de A. cantonensis fue establecida para cada una de las técnicas de análisis utilizadas. Resultados: se confirmó la presencia de A. cantonensis en el tejido pulmonar de los especímenes de L. fulica recolectados en la ciudad de Buenaventura, Valle del Cauca, Colombia. La tasa de detección alcanzanda a través de la técnica de identificación visual mediante análisis histológico fue del 89%, mientras que usando la técnica de PCR convencional fue del 95% y de PCR en tiempo real fue del 100%. Conclusión: este estudio confirma por primera vez la presencia de A. cantonensis asociado a especímenes de L. fulica en Colombia. Por lo tanto, se sugiere que la meningitis eosinofílica sea propuesta como una enfermedad emergente en Colombia.

Angiostrongylus (Parastrongylus) cantonensis en huéspedes intermediarios y definitivos en Ecuador, 2014-2017 / Angiostrongylus (Parastrongylus) cantonensis on intermediate and definitive hosts in Ecuador, 2014-2017

Resumen Introducción. Angiostrongylus cantonensis es un serio problema de salud pública y está ampliamente distribuido en el país. Cuando el parásito infecta a los caracoles terrestres Achatina, se enquista en su interior y puede infectar accidentalmente a las personas y otros mamíferos. Objetivo. Establecer la distribución geográfica de A. cantonensis en huéspedes intermediarios (Achatina fulica) y definitivos (Rattus spp.) en Ecuador entre el 2014 y el 2017. Materiales y métodos. Se recolectaron 2.908 ejemplares de A. fulica en 16 provincias utilizando el método de captura por unidad de esfuerzo durante 30 minutos. Se capturaron 211 ejemplares de las especies huéspedes, de los cuales 20 eran Rattus rattus y 191 R. norvegicus. Los ejemplares fueron transportados para su análisis al Instituto Nacional de Salud Pública e Investigación en Guayaquil. En los tejidos del caracol se identificaron y se contabilizaron larvas L3 que luego se inocularon en ratas de laboratorio para reproducir el ciclo de vida. En los roedores se disecaron los cerebros, los corazones, las arterias pulmonares y los pulmones, y se identificaron los parásitos por morfología taxonómica. Resultados. De los caracoles recolectados se encontraron 441 positivos para A. cantonensis (15,2 %) y un total de 6.166 larvas L3. En los ejemplaresRattus spp. capturados (211), 77 (36,5 %) estaban infectados con A. cantonensis, con un total de 220 parásitos (larvas L4-L5 y adultos). Conclusiones. Se constató la presencia de A. cantonensis en varias provincias, lo que confirma el carácter endémico de esta zoonosis en el territorio nacional. La presencia de Rattus spp., huésped definitivo del parásito, y de huéspedes intermediarios, indica el potencial zoonótico de esta infección parasitaria.

Abstract Introduction: Angiostrongylus cantonensis is a serious public health problem and is widely distributed in the country. When the parasite infects the snails, it becomes deeply embedded in their interior and accidentally, it can infect people and other mammals. Objective: To establish the geographical distribution of A. cantonensis intermediate hosts (Achatina fulica) and definitive hosts (Rattus spp.) in Ecuador from 2014 to 2017. Materials and methods: We collected 2,908 A. fulica specimens in 16 provinces using the capture method per unit of effort for 30 minutes. We captured 211 hosts of which 20 were Rattus rattus and 191 R. norvegicus. The specimens were transported to the Instituto Nacional de Salud Pública e Investigación in Guayaquil where the larvae L3 were identified and counted in the tissues of the snail, which were then inoculated in laboratory rats to reproduce the life cycle. In the rodents, the brains, hearts, lung arteries and lungs were dissected, and the parasites were identified by taxonomic morphology. Results: Of the snails harvested, 441 were positive for A. cantonensis (15.2%) and a total of 6,166 L3 larvae were found; 77 (36.5%) specimens of Rattus spp., were infected with A. cantonensis and a total of 220 parasites (L4-L5 larvae and adult worms) were collected. Conclusions: We confirmed the presence of A. cantonensis in several provinces, which ratifies the endemic nature of this zoonosis in the national territory. Rattus spp. specimens constitute the definitive hosts of the parasite, which together with the presence of intermediate hosts, indicates the zoonotic potential of this parasitic infection.

Infección por Angiostrongylus cantonensis (Nematoda: Metastrongylidae) en Rattus rattus (Rodentia: Muridae) en una localidad de La Habana, Cuba / Infection by Angiostrongylus cantonensis (Nematoda: Metastrongylidae) in Rattus rattus (Rodentia: Muridae) in a locality of Havana, Cuba

Introducción: La meningoencefalitis eosinofílica producida por Angiostrongylus cantonensis (Chen, 1935), es una zoonosis emergente presente en Cuba. En el país existen escasos estudios de prevalencia de infección en los hospederos definitivos, que puedan determinar sitios de riesgo para el establecimiento de medidas efectivas en la prevención de la enfermedad. Objetivo: Determinar la prevalencia de infección por A. cantonensis en una población natural de R. rattus, su relación con la estructura poblacional y la época del año en una finca que pertenece al Programa de la Agricultura Urbana y Suburbana de Cuba. Material y Métodos: Se realizó un estudio descriptivo en el municipio La Lisa, La Habana. Se hicieron capturas de roedores mensuales durante los períodos lluvioso y poco lluvioso. Se examinaron las arterias pulmonares de los roedores capturados en búsqueda de parásitos adultos. El índice parasitológico de prevalencia fue calculado y comparadas las frecuencias entre los períodos del año y la edad ecológica. Resultados: Se capturaron 63 roedores identificados como Rattus rattus, de ellos 46,03 por ciento estuvo infectado con A. cantonensis, con un incremento de la infección en los individuos adultos (59,46 por ciento) y en el período lluvioso (55,88 por ciento). Conclusiones: Se demuestra por primera vez en Cuba la infección de A. cantonensis en R. rattus. La presencia de individuos adultos, la alta abundancia de roedores y la temporada lluviosa son los factores que incidieron en una mayor infección de A. cantonensis, y que aumentan la probabilidad de transmisión a los hospederos intermediarios y, por ende, el riesgo de transmisión al humano(AU)

Introduction: Eosinophilic meningitis caused by Angiostrongylus cantonensis (Chen, 1935) is an emergent zoonosis present in Cuba. In the country, few studies about the prevalence of infection in definitive hosts, which can determine risk sites for the establishment of effective measures to prevent the disease, have not been carried out so far. Objective: To determine the prevalence of infection with Angiostrongylus cantonensis in a natural population of Rattus rattus, its relationship with the population structure, and the season of the year in an urban farm field belonging to the Programme of Urban and Suburban Agriculture of Cuba. Material and Methods: A descriptive study was conducted in La Lisa Municipality, Havana, Cuba. The rats were collected monthly during the rainy and dry seasons. The pulmonary arteries of the captured rodents were examined for adult worms. The prevalence of parasitological indices was calculated. The frequencies of infection were compared between the seasons of the year and ecological ages. Results: A total of 63 rodents identified as Rattus rattus were captured. Of the total of individuals captured, 46.03 percent were infected with A. cantonensis, with an increase of infection in adult individuals (59.46 percent) and during the rainy season (55.88 percent). Conclusions: The infection of A. cantonensis in its definitive host R. rattus, and its circulation in the study area in the analyzed period was demonstrated for the first time in Cuba. The presence of adult rats, the high quantity of rodents and the rainy season were the factors that contributed to a greater infection of A. cantonensis, which increase the probability of transmission to intermediate hosts, and consequently, the risk of transmission to humans(AU)

Human neuroimmune response against angiostrongylus cantonensis

Introduction: Angiostrongylus cantonensis is a zoonotic pathogen that causes human angiostrongyliasis; its main clinical manifestation is eosinophilic meningitis. It was reported in Cuba for the first time in America. Objective: To review the main immunological findings about the human neuroimmune response against this parasite. Methods: This paper is based on a review of the papers mainly from Cuban authors published in the last 10 years about the human neuroimmune response against this helmint. This information becomes more relevant after the introduction of the African giant snail Lissachatina fulica in Cuba in 2014. Results: The humoral immune response is based on the immunoglobulin intrathecal synthesis. When the third-stage larvae go to the central nervous system at the first lumbar puncture there are no major immunoglobulin synthesis. One week later an immune intrathecal response is done by a two-class major immunoglobulin class mainly IgG+ IgA Intrathecal activation of complement is evident of intrathecal synthesis of major immunoglobulins during this disease. The activation of complement system components in cerebrospinal fluid is relevant to the understanding of this tropical disease, which is emerging in the Western hemisphere. Intrathecal synthesis of at least one of the major immunoglobulins and a wide spectrum of patterns may be observed. Although intrathecal synthesis of C3c and IgE is always present, C4 intrathecal synthesis does not occur in every patient. The diversity of intrathecal synthesis and activation of the different complement pathways enables their division into three variant groups. In each one could be finding the activation of one or several complement pathways including the participation of MBL, MASP-2 and ficolins as part of the lectin pathway complement activation. Conclusion: The neuroimmune response against Angiostrongylus cantonensis eosinophilic meningoencephalitis is an example of the host-parasite interaction(AU)