First identification of Angiostrongylus spp. in Lissachatina fulica and Cornu aspersum in Antioquia, Colombia / Identificación de Angiostrongylus spp. en Lissachatina fulica y Cornu aspersum en Antioquia, Colombia

INTRODUCTION: Abdominal and neural angiostrongyliasis caused by Angiostrongylus costaricensis and A. cantonensis, respectively, are zoonotic diseases involving snails as intermediate hosts. Colombia has already reported human cases, and the increasing distribution of Lissachatina fulica and Cornu aspersum raises public health concerns due to the potential risk of disease transmission in areas where parasites and hosts coexist. OBJECTIVE: To identify the presence of Angiostrongylus spp. in snail species L. fulica and C. aspersum in Antioquia, Colombia. MATERIALS AND METHODS: This prospective cross-sectional study had a population of 5,855 L. fulica and C. aspersum snails captured in the ten towns of the Valle de Aburrá (Antioquia, Colombia), 169 samples were collected in 28 sampling points. Lung tissues of the collected snails were dissected and analyzed to detect Angiostrongylus spp. through molecular techniques. RESULTS: Angiostrongylus spp. were identified in both L. fulica and C. aspersum. Angiostrongylus costaricensis was detected in 18 pooled prevalence of 30% (95% CI = 19.2-43.3), and Medellín was the municipality with the highest number of positive samples (33.3%). Seventy-two-point-two percent of the positive places reported the presence of rodents. None of the tests were positive for A. cantonensis. CONCLUSION: Our findings provide important insights into the epidemiology and distribution of Angiostrongylus spp. in Antioquia, Colombia. The identification of these parasitic nematodes in L. fulica and C. aspersum highlights the potential role of these snails as intermediate hosts in the transmission of Angiostrongylus spp. infections in the Valle de Aburrá, with implications for human and veterinary health.

Introducción: La angiostrongiliasis abdominal y neura ­causadas por Angiostrongylus costaricensis y A. cantonensis, respectivamente­ son zoonosis que involucran caracoles como huéspedes intermediarios. Colombia ya ha reportado casos en humanos y la ampliación de la distribución de Lissachatina fulica y Cornu aspersum aumenta la preocupación en salud pública debido al riesgo potencial de transmisión en áreas donde los parásitos y sus huéspedes coexisten. Objetivo: Identificar la presencia de Angiostrongylus spp. en caracoles de las especies L. fulica y C. aspersum en Antioquia (Colombia). Materiales y métodos: Se llevó a cabo un estudio transversal prospectivo con una población de 5.855 caracoles de L. fulica o C. aspersum, capturados en diez ciudades del valle de Aburrá; 169 muestras fueron recolectadas en 28 puntos de muestreo. Se disecaron los tejidos pulmonares de los caracoles y se emplearon técnicas moleculares para detectar la presencia de Angiostrongylus spp. Resultados: Angiostrongylus costaricensis fue detectado en 18 muestras agrupadas (30 %; IC95%: 19,2-43,3), tanto en L. fulica como en C. aspersum. Medellín fue el municipio con el mayor número de muestras positivas (33,3 %). El 72,2 % de los lugares positivos reportaron la presencia de roedores. Ninguna de las pruebas fue positiva para A. cantonensis. Conclusión: Estos hallazgos brindan información importante sobre la distribución de Angiostrongylus spp. en Antioquia (Colombia). La identificación de estos nemátodos en L. fulica y C. aspersum resalta el papel potencial de estos caracoles como huéspedes intermediarios en la transmisión de infecciones por Angiostrongylus en el valle de Aburrá, con implicaciones para la salud humana y veterinaria.

First identification of Angiostrongylus spp. in Lissachatina fulica and Cornu aspersum in Antioquia, Colombia / Identificación de Angiostrongylus spp. en Lissachatina fulica y Cornu aspersum en Antioquia, Colombia

Abstract Introduction. Abdominal and neural angiostrongyliasis caused by Angiostrongylus costaricensis and A. cantonensis, respectively, are zoonotic diseases involving snails as intermediate hosts. Colombia has already reported human cases, and the increasing distribution of Lissachatina fulica and Cornu aspersum raises public health concerns due to the potential risk of disease transmission in areas where parasites and hosts coexist. Objective. To identify the presence of Angiostrongylus spp. in snail species L. fulica and C. aspersum in Antioquia, Colombia. Materials and methods. This prospective cross-sectional study had a population of 5,855 L. fulica and C. aspersum snails captured in the ten towns of the Valle de Aburrá (Antioquia, Colombia), 169 samples were collected in 28 sampling points. Lung tissues of the collected snails were dissected and analyzed to detect Angiostrongylus spp. through molecular techniques. Results. Angiostrongylus spp. were identified in both L. fulica and C. aspersum. Angiostrongylus costaricensis was detected in 18 pooled prevalence of 30% (95% CI = 19.2-43.3), and Medellín was the municipality with the highest number of positive samples (33.3%). Seventy-two-point-two percent of the positive places reported the presence of rodents. None of the tests were positive for A. cantonensis. Conclusion. Our findings provide important insights into the epidemiology and distribution of Angiostrongylus spp. in Antioquia, Colombia. The identification of these parasitic nematodes in L. fulica and C. aspersum highlights the potential role of these snails as intermediate hosts in the transmission of Angiostrongylus spp. infections in the Valle de Aburrá, with implications for human and veterinary health.

Resumen Introducción. La angiostrongiliasis abdominal y neura -causadas por Angiostrongylus costaricensis y A. cantonensis, respectivamente- son zoonosis que involucran caracoles como huéspedes intermediarios. Colombia ya ha reportado casos en humanos y la ampliación de la distribución de Lissachatina fulica y Cornu aspersum aumenta la preocupación en salud pública debido al riesgo potencial de transmisión en áreas donde los parásitos y sus huéspedes coexisten. Objetivo. Identificar la presencia de Angiostrongylus spp. en caracoles de las especies L. fulica y C. aspersum en Antioquia (Colombia). Materiales y métodos. Se llevó a cabo un estudio transversal prospectivo con una población de 5.855 caracoles de L. fulica o C. aspersum, capturados en diez ciudades del valle de Aburrá; 169 muestras fueron recolectadas en 28 puntos de muestreo. Se disecaron los tejidos pulmonares de los caracoles y se emplearon técnicas moleculares para detectar la presencia de Angiostrongylus spp. Resultados. Angiostrongylus costaricensis fue detectado en 18 muestras agrupadas (30 %; IC95%: 19,2-43,3), tanto en L. fulica como en C. aspersum. Medellín fue el municipio con el mayor número de muestras positivas (33,3 %). El 72,2 % de los lugares positivos reportaron la presencia de roedores. Ninguna de las pruebas fue positiva para A. cantonensis. Conclusión. Estos hallazgos brindan información importante sobre la distribución de Angiostrongylus spp. en Antioquia (Colombia). La identificación de estos nemátodos en L. fulica y C. aspersum resalta el papel potencial de estos caracoles como huéspedes intermediarios en la transmisión de infecciones por Angiostrongylus en el valle de Aburrá, con implicaciones para la salud humana y veterinaria.

Reaching new lands: Updating the distribution of Angiostrongylus cantonensis in South America with the first record in Argentina.

BACKGROUND: Angiostrongylus cantonensis, commonly known as the rat lungworm, is a metastrongyloid nematode found primarily not only in tropical and subtropical regions but also in temperate areas and considered the leading cause of eosinophilic meningitis in humans. Synanthropic rodents such as Rattus norvegicus and Rattus rattus are the most frequent definitive hosts of this parasite. METHODS AND RESULTS: The presence of this parasite was detected in the pulmonary arteries of three specimens of R. norvegicus in the city of Buenos Aires representing the species' southernmost known record in natural hosts. Species confirmation was achieved through partial sequences of 18S and COI genes. By comparing the COI gene sequences with those available in GenBank through the construction of a haplotype network, we obtained that the analysed specimen presents high similarity with those reported in Japan and Southeast Asia. CONCLUSIONS: All infected rats were captured in an area surrounding a port with significant import and export activity, suggesting that A. cantonensis may have been introduced through commercial ships. Specifically, the parasite was detected in a neighbourhood with vulnerable socio-economic conditions and in a nature reserve, which exhibit biotic and abiotic characteristics conducive to sustaining high-density rat populations, scattered waste, areas of spontaneous vegetation, debris accumulation and flooded areas or lagoons offering suitable habitats for intermediate hosts such as snails. Thus, the close proximity of the port to these sites creates a favourable ecological context for the establishment of A. cantonensis. This study shows the need to conduct research to detect A. cantonensis in non-endemic areas but with the characteristics that promote its arrival and development of its life cycle in order to implement control measures to prevent expansion of this parasite and its transmission to humans and other animals.

Diagnostic criteria and case definitions for abdominal angiostrongyliasis: a systematic review from the Brazilian experience.

Although rare, Angiostrongylus costaricensis infection may be a more prevalent etiology of inflammatory bowel disease than ulcerative colitis and Chron's disease in endemic areas in Central and South America. The present study reviewed the occurrence of A. costaricensis in Brazil, its clinical presentation and pathology; and proposed diagnostic criteria and case definitions for abdominal angiostrongyliasis (AA). Southern and southeastern Brazilian regions are the main endemic areas, and AA affects both genders and all age groups. A review of all 23 published reports of 51 Brazilian patients highlighted the following features that were subsequently classified as minor diagnostic criteria: abdominal pain, palpable mass in the right lower abdominal quadrant, history of exposure, ileocecal tumor, and intestinal perforation with wall thickening. Proposed major criteria include right lower quadrant abdominal pain, blood eosinophilia, positive serology (antibody detection), intense eosinophilic infiltration that involves all strata of the intestinal wall, eosinophilic granulomatous reaction, and eosinophilic vasculitis. In addition to the definitions of suspected and possible cases according to increasing strength of evidence of this infection, demonstration of worms/eggs/larvae in tissues or Angiostrongylus DNA in tissues or serum are required for a confirmed diagnosis. The application of the proposed criteria and definitions may improve patient management, epidemiologic surveillance, and identification of new endemic areas.

Semperula wallacei (Mollusca, Veronicellidae) um hospedeiro natural recém-descoberto de Angiostrongylus cantonensis (Nematoda, Angiostrongylidae) na Bacia do Pacífico.

Semperula wallacei (Issel, 1874) is a species of terrestrial slug that occurs in southeast China and the Pacific Basin and is the only species of its genus that occurs beyond the Oriental region and to the east of Wallace's line in the Australian region, where it has probably been introduced. In this study, we report for the first time S. wallacei as an intermediate host for Angiostrongylus cantonensis (Chen, 1935) based on histological and molecular analyses of slugs from Tuamasaga, Samoa, deposited at the Medical Malacological Collection (Fiocruz-CMM). DNA was obtained from the deparafinized tissues scraped from specimen slides. Polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) targeted to the internal transcribed spacer 2 (ITS2) region were carried out using the restriction enzyme Cla I. The RFLP profile observed for our larval specimen of S. wallacei was identical to the profile previously established for A. cantonensis, demonstrating that S. wallacei can be naturally infected with A. cantonensis and is likely to be an intermediate host for this parasitic nematode species in the field. The potential for geographical range expansion of S. wallacei in the Pacific Basin, its small size, and the general role of veronicellids as crop pests and hosts of nematodes, indicate the significance of S. wallacei as an invasive species in the Pacific Basin. Our work also highlights the importance of biological collections for investigating the environmental impact of invasive species on agriculture, public health, and biodiversity conservation.

Fatal neural angiostrongyliasis in the Bolivian squirrel monkey (Saimiri boliviensis boliviensis) leading to defining Angiostrongylus cantonensis risk map at a zoo in Australia.

Neural angiostrongyliasis (NA) is a parasitic disease caused by Angiostrongylus cantonensis (rat lungworm). This study presents a case of NA in a captive Bolivian squirrel monkey from a zoo in western Sydney, Australia. The objective was to identify the A. cantonensis cox1 haplotype responsible for the infection and compare its mitochondrial DNA (mtDNA) to known Australian mtDNA. An epidemiological investigation was conducted to assess the risk of infection, focusing on the resident rat population in the zoo. Methods involved trapping rats and collecting rat faeces for Angiostrongylus detection, speciation, and cox1 haplotype confirmation. Various techniques were employed, including necropsy, morphological examination, and molecular methods such as ITS-2 qPCR, cox1 sequencing, and ITS-2 metabarcoding. Cluster analysis of rat faeces distribution and Angiostrongylus detection utilised an equal sampling effort (ESE) approach. Gastropods were collected throughout the study for Angiostrongylus surveillance using a hypersensitive qPCR assay. Results revealed significant clustering of rat faeces near exhibits with fresh food provision and absence of predators. Angiostrongylus-positive faeces were uniformly distributed across the zoo property. Mitochondrial DNA analysis confirmed the presence of the Ac13 haplotype of A. cantonensis in the monkey. Morphology, ITS-2 metabarcoding and partial cox1 sequencing detected only A. cantonensis, with the Ac13 cox1 haplotype predominating. A high prevalence of infection (64%, 9/14) was found in brown rats, with quantification of larvae indicating high shedding rates. Co-infections with both Ac13 and local SYD.1 A. cantonensis cox1 haplotypes were observed. Only three gastropods (all of which were Angiostrongylus-negative) were found in the survey. To minimise the risk of exposure for susceptible species, targeted rodent control was implemented in areas with higher exposure risk. A potential strategy (which requires further exploration) to consider for future zoo design was suggested. This study provides insights into the epidemiology and genetic diversity of A. cantonensis in Australia, emphasising the importance of control measures to prevent future outbreaks.

The recent introduction of Angiostrongylus cantonensis and its intermediate host Achatina fulica into Guadeloupe detected by phylogenetic analyses.

BACKGROUND: Angiostrongylus cantonensis (rat lungworm) is the main pathogen responsible for eosinophilic meningitis in humans. One of its intermediate snail hosts, Achatina fulica, was already present in many countries around the world before it appeared in the West Indies in the late 1980s. In the French territories in the Caribbean and northern South America, the first cases of human neuroangiostrongyliasis were reported in Martinique, Guadeloupe and French Guiana in 2002, 2013 and 2017, respectively. In order to better characterize angiostrongyliasis in Guadeloupe, particularly its geographical origin and route of introduction, we undertook molecular characterization of adult worms of Angiostrongylus cantonensis and its intermediate host Achatina fulica. METHODS: Genomic DNA of adult Angiostrongylus cantonensis and Achatina fulica was extracted and amplified by polymerase chain reaction (PCR) targeting the mitochondrial genes cytochrome B and C for A. cantonensis and 16S ribosomal RNA for A. fulica. The PCR products were sequenced and studied by phylogenetic analysis. RESULTS: Cytochrome B and cytochrome C molecular markers indicate a monophyletic lineage of A. cantonensis adult worms in Guadeloupe. Two sequences of A. fulica were identified. CONCLUSIONS: These results confirm the recent introduction of both Angiostrongylus cantonensis and Achatina fulica into Guadeloupe. Achatina fulica in Guadeloupe shares a common origin with those in Barbados and New Caledonia, while Angiostrongylus cantonensis in Guadeloupe shares a common origin with those in Brazil, Hawaii and Japan.

A practical guide for the diagnosis of abdominal angiostrongyliasis caused by the nematode Angiostrongylus costaricensis.

Abdominal angiostrongyliasis (AA) is a severe parasitic infection caused by the nematode Angiostrongylus costaricensis. This disease is characterized by abdominal pain, a strong inflammatory eosinophilic response in the blood and tissues, and eventually intestinal perforation. Diagnosis of AA is challenging since there are no commercially available serological kits for A. costaricensis, and thus, histopathological analysis remains the gold standard. Herein we provide a decision flowchart for clinicians to improve the diagnosis of AA based on a patient's clinical manifestations, laboratory findings, macroscopic observations of the gut lesions, as well as characteristic microscopic alterations in biopsies. A brief discussion of the available polymerase chain reaction and in-house serological methods is also presented. The aim of this mini-review is to improve the diagnosis of AA, which should lead to prompt detection of cases and better estimates of the epidemiology and geographical distribution of A. costaricensis.

Perforación cecal por angiostrongiliasis en un adulto mayor / Cecal perforation due to angiostrongyliasis in an elderly patient

La angiostrongiliasis abdominal es una enfermedad parasitaria causada por el género Angiostrongylus costaricensis, un nematodo que infecta a los humanos a través de las secreciones de caracoles o babosas, sus huéspedes definitivos. Costa Rica es el país que se considera más endémico, se ha evidenciado en distintas revisiones que la mayoría de los casos se presentan en niños y personas del sexo masculino. Presentación del caso. Se trata de una mujer de 74 años, que consultó por dolor abdominal agudo, de cuatro días de evolución, acompañado de náuseas, vómitos e hiporexia. Los exámenes de laboratorio reportaron leucocitosis leve y examen general de orina negativo. La ultrasonografía abdominal reportó una masa sólida, heterogénea, mal circunscrita en flanco derecho, esto llevó a la sospecha de una apendicitis aguda. Intervención terapéutica. Se realizó una laparotomía exploradora, con la extirpación de una tumoración de colon perforado que abarcaba desde el ciego hasta el tercio proximal de colon ascendente, además, se realizó una anastomosis de íleo transversa, sin mayor complicación. Evolución clínica. Se manejó con antibióticos y analgésicos, fue dada de alta a los nueve días posteriores al procedimiento, sin complicaciones menores. La biopsia reportó huevos de parásitos consistentes con Angiostrongylus sp

bdominal angiostrongyliasis is a parasitic disease caused by the genus Angiostrongylus costaricensis, a nematode that infects humans through the secretions of snails or slugs, its definitive hosts. Costa Rica is considered the most endemic country, and it has been shown in different reviews that most cases occur in children and males. Case presentation. The patient was a 74-year-old woman who consulted for acute abdominal pain, with four days of evolution, accompanied by nausea, vomiting, and hyporexia. Laboratory tests reported mild leukocytosis and a negative general urine test. Abdominal ultrasonography reported a solid heterogeneous mass, poorly circumscribed in the right lateral abdomen, which led to the suspicion of acute appendicitis. Treatment. An exploratory laparotomy was performed, with the removal of a perforated colon tumor that spanned from the cecum to the proximal third of the ascending colon, in addition, a transverse ileum anastomosis was performed, without further complication. Outcome. She was managed with antibiotics and analgesics and was discharged nine days after the procedure, without complications. The biopsy showed parasite eggs consistent with Angiostrongylus sp

Parasitism in Rattus rattus and sympatric Achatina fulica by Angiostrongylus cantonensis in an urban park in southeast Brazil.

In this study, rodents (Rattus rattus) and mollusks (Achatina fulica) were captured in a small forest located in a large metropolitan city in Brazil, and they were examined to investigate possible parasitism by Angiostrongylus cantonensis. The parasites were recovered as helminths from the pulmonary arteries of the synanthropic rodents and as third-stage larvae (with Metastrongylidae family characteristics) from the mollusks. To confirm the species, these larvae were used to experimentally infect Rattus norvegicus for the posterior recovery of adult helminths. To identify the adult helminths, morphological, morphometric, molecular, and phylogenetic techniques were employed. Furthermore, we also characterized the histological lesions associated with parasitism in naturally infected definitive hosts. Our results demonstrated the occurrence of a natural life cycle of A. cantonensis (with the presence of adult helminths) in definitive hosts, Rattus rattus, and third-stage larvae in an intermediate host, A. fulica. In free-living rodents, lesions of granulomatous pneumonia in the lungs and meningitis in the brain were also found. These results warn of the risk of accidental transmission of A. cantonensis to human residents around the park because of the extensive interaction among the fauna of the park, domestic animals, and the surrounding human population.

Parasitism of terrestrial gastropods by medically-important nematodes in Brazil.

An ample variety of parasitic associations are found between mollusks and nematodes, in which the mollusks may act as intermediate, paratenic or definitive hosts. Some free-living nematodes, in particular those of the order Rhabditida, are also found frequently in terrestrial mollusks. The present study reviews the results of the parasitological testing on samples of terrestrial mollusks conducted at the Brazilian National Reference Laboratory for Schistosomiasis and Malacology between 2008 and 2021. The samples were supplied primarily by the public health authorities from the different regions of Brazil, but also by research institutions and general population. The mollusks were processed individually and the obtained larvae were identified from their morphology and, whenever necessary, by molecular analysis. A total of 1,919 service orders were registered during the period, including 19,758 mollusk specimens collected from 23 of the 26 Brazilian states, as well as the Federal District, totalizing 145 municipalities. There was a marked predominance of the synanthropic species that are widely distributed in Brazil-Achatina fulica (87.08%), Bulimulus tenuissimus (4.18%), Bradybaena similaris (2.06%), and Sarasinula linguaeformis (1.50%). Of the 16,750 terrestrial mollusks examined, nematodes were recorded in 1,308 service orders, with the predominance of the superfamily Metastrongyloidea, in 616 service orders. They included Angiostrongylus cantonensis, rat lungworm, which was found in 252 samples, and Aelurostrongylus abstrusus in 145 samples. Free-living nematodes were found in 952 samples, Ancylostoma caninum and Cruzia tentaculata (previously identified as Strongyluris sp.) in one and 275 samples, respectively, and other parasites in 210 samples (not identified). The results highlight the diversity of the associations between nematodes and terrestrial mollusks in Brazil, in particular invasive and synanthropic species, with emphasis on the giant African land snail, Achatina fulica. They demonstrate the prominent role of this species of mollusk in the transmission of medically-important nematodes, which affect the health of both humans and animals, in particular eosinophilic meningitis, which is caused by Angiostrongylus cantonensis. This reinforces the need for more studies, and justify the growing demand for information as well as parasitological diagnosis of this mollusk, given its wide distribution in Brazil and its impact as an urban pest.

Conocimientos, percepciones y prácticas de médicos de atención primaria en Ecuador sobre la infección por Angiostrongylus cantonensis / Knowledge, perceptions and practice of primary healthcare doctors in Ecuador on Angiostrongylus cantonensis infection

Introducción: La angiostrongiliasis humana presenta un amplio espectro clínico: desde una infección asintomática a meningitis eosinofílica, meningoencefalitis eosinofílica y angiostrongiliasis ocular. Objetivo: Determinar los conocimientos, percepciones y prácticas en relación con la infección por Angiostrongylus cantonensis que poseen médicos de atención primaria de la República del Ecuador. Métodos: Se realizó un estudio observacional descriptivo. Se diseñó, validó y aplicó una encuesta sobre conocimientos, percepciones y prácticas a 163 médicos de atención primaria de las provincias Napo y Guayas, entre los meses de noviembre y diciembre de 2017. La información obtenida se almacenó en una base de datos Microsoft Access y se realizó un análisis de frecuencias a las respuestas dadas a cada una de las preguntas. Resultados: Se encontraron conocimientos insuficientes, percepciones inadecuadas y prácticas incorrectas en relación con la angiostrongiliasis. Conclusiones: Estos resultados orientan hacia la implementación de un programa de intervención educativa en médicos de atención primaria con el fin de atenuar las deficiencias encontradas, para incidir de forma positiva en comunidades donde existe la presencia de hospederos intermediarios y definitivos infectados y un riesgo potencial de infección.

Introduction: Human angiostrongyliasis presents a broad clinical spectrum, which ranges from asymptomatic infection to eosinophilic meningitis, eosinophilic meningoencephalitis, and ocular angiostrongyliasis. Objective: To determine the knowledge, perceptions, and practice of primary healthcare doctors in the Republic of Ecuador regarding Angiostrongylus cantonensis infection. Methods: It was conducted a descriptive observational study. A survey on knowledge, perceptions, and practice was designed, validated, and applied to 163 primary healthcare doctors from Napo and Guayas provinces between November and December 2017. The information obtained was stored in a Microsoft Access 2016 database, and a frequency analysis was performed to the answers provided to every question. Results: Insufficient knowledge, inadequate perceptions, and incorrect practice regarding angiostrongyliasis were found. Conclusions: The results evidenced the need to implement an educational intervention program to primary healthcare doctors aimed at reducing the deficiencies found to have a positive impact on the communities where the intermediate and definitive hosts and a potential infection risk exist.

Nationwide Seroprevalence Survey of Angiostrongylus vasorum-Derived Antigens and Specific Antibodies in Dogs from Colombia.

Angiostrongylus vasorum is a cardiopulmonary nematode, causing several clinical manifestations in dogs, e.g., severe respiratory signs, coagulopathy, and gastrointestinal or neurological signs. In the last decades, this parasite has been described to spread and emerge in Europe and North America. Scant studies on A. vasorum occurrence in South America exist. Recently, A. vasorum was detected in gastropod intermediate hosts in Colombia, where data on definitive host prevalence, e.g., dogs and wild canids, are still limited. Therefore, the sera of 955 dogs, varying in age and breed from seven different departments all over Colombia, were collected and analysed for A. vasorum antigens and parasite-specific antibodies by ELISA. In total, 1.05 % (n = 10; 95 % CI 0.40-1.69) of the samples were antigen-positive and 2.62 % (n = 25; 95 % CI 1.61-3.63) were antibody-positive. These results confirm the presence of A. vasorum in Colombia, although positive results in antigen and antibody reactions in the same dog were not detected. This study is the first large-scale survey on A. vasorum seroprevalences in dogs from Colombia.

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 an Atypical Presenilin: Epitope Mapping, Characterization, and Development of an ELISA Peptide Assay for Specific Diagnostic of Angiostrongyliasis.

BACKGROUND: Angiostrongyliasis, the leading cause universal of eosinophilic meningitis, is an emergent disease due to Angiostrongylus cantonensis (rat lungworm) larvae, transmitted accidentally to humans. The diagnosis of human angiostrongyliasis is based on epidemiologic characteristics, clinical symptoms, medical history, and laboratory findings, particularly hypereosinophilia in blood and cerebrospinal fluid. Thus, the diagnosis is difficult and often confused with those produced by other parasitic diseases. Therefore, the development of a fast and specific diagnostic test for angiostrongyliasis is a challenge mainly due to the lack of specificity of the described tests, and therefore, the characterization of a new target is required. MATERIAL AND METHODS: Using bioinformatics tools, the putative presenilin (PS) protein C7BVX5-1 was characterized structurally and phylogenetically. A peptide microarray approach was employed to identify single and specific epitopes, and tetrameric epitope peptides were synthesized to evaluate their performance in an ELISA-peptide assay. RESULTS: The data showed that the A. cantonensis PS protein presents nine transmembrane domains, the catalytic aspartyl domain [(XD (aa 241) and GLGD (aa 332-335)], between TM6 and TM7 and the absence of the PALP and other characteristics domains of the class A22 and homologous presenilin (PSH). These individualities make it an atypical sub-branch of the PS family, located in a separate subgroup along with the enzyme Haemogonchus contournus and separated from other worm subclasses. Twelve B-linear epitopes were identified by microarray of peptides and validated by ELISA using infected rat sera. In addition, their diagnostic performance was demonstrated by an ELISA-MAP4 peptide. CONCLUSIONS: Our data show that the putative AgPS is an atypical multi-pass transmembrane protein and indicate that the protein is an excellent immunological target with two (PsAg3 and PsAg9) A. costarisencis cross-reactive epitopes and eight (PsAg1, PsAg2, PsAg6, PsAg7, PsAg8, PsAg10, PsAg11, PsAg12) apparent unique A. cantonensis epitopes. These epitopes could be used in engineered receptacle proteins to develop a specific immunological diagnostic assay for angiostrongyliasis caused by A. cantonensis.

Epidemiological, clinical and laboratory aspects of Angiostrongylus cantonensis infection: an integrative review / Aspectos epidemiológicos, clínicos e laboratoriais de infecção por Angiostrongylus cantonensis: uma revisão integrativa

This integrative literature review study analyzes the findings of the last 5 years of the parasite Angiostrongylus cantonensis. It is known that this nematode is found in the pulmonary arteries of rats, where it remains as a definitive host. From mice, the cycle spreads to animals, such as snails, which in contact with humans can trigger the disease. In humans, the parasite causes several neurological, abdominal manifestations and mainly meningitis. Based on the review of studies, its epidemiology shows worldwide distribution, although there are endemic cases for this parasite, such as asian countries. Laboratory findings generally showed altered CSF with turbidity, increased protein and eosinophilia, which generated meningeal signs in the patient, moreover MRI exams showed multiple alterations. Rare findings of the nematode in the eyeball, lung and signs of peritoneal inflammation were reported, which requires further studies to understand the whole pathophysiology. Finally, conservative treatment based on anthelmintics and anti-inflammatories brought good responses, although there are reports of deaths, which demonstrates the importance in the prevention and therapy of this disease.

Este estudo de revisão integrativa da literatura analisa os achados dos últimos 5 anos do parasita Angiostrongylus cantonensis. Sabe-se que esse nematoide é encontrado nas artérias pulmonares de ratos, onde permanece como hospedeiro definitivo. Dos camundongos, o ciclo se espalha para os animais, como os caracóis, que em contato com humanos podem desencadear a doença. Em humanos, o parasita causa diversas manifestações neurológicas, abdominais e principalmente meningite. Com base na revisão de estudos, sua epidemiologia mostra distribuição mundial, embora existam casos endêmicos para esse parasito, como países asiáticos. Os achados laboratoriais geralmente mostraram LCR alterado com turbidez, aumento de proteínas e eosinofilia, o que gerou sinais meníngeos nos pacientes, além disso, os exames de ressonância magnética mostraram múltiplas alterações. Foram relatados achados raros do nematoide no globo ocular, pulmão e sinais de inflamação peritoneal, o que requer mais estudos para o entendimento de toda a fisiopatologia. Por fim, o tratamento conservador à base de anti-helmínticos e anti-inflamatórios trouxe boas respostas, embora haja relatos de óbitos, o que demonstra a importância na prevenção e terapia dessa doença.

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)

Immunoanalysis of different antigenic preparations of Angiostrongylus cantonensis for neuroangiostrongyliasis diagnosis improvement

BACKGROUND Angiostrongylus cantonensis is the etiological agent of neuroangiostrongyliasis in humans, which is developed in gastropods and vertebrate species, mainly rodents. Human transmission occurs through consumption of molluscs and paratenic hosts infected with L3, and the migration of larvae to the central nervous system causes eosinophilic meningitis. Laboratory diagnosis is based on molecular and immunological tests, using young or adult females as a source of antigens. However, these tests give positive results only after several weeks of symptoms onset and also cross-reactions with others parasite infections may occur. OBJECTIVES The purpose of this work was to study different antigenic preparations of distinct evolutionary phases of A. cantonensis, in order to improve serological techniques for disease immunodiagnosis. METHODS For this purpose, antigenic fractions of different evolutionary forms were evaluated by Dot-enzyme-linked immunosorbent assay (Dot-ELISA) and Western blot using serum samples. FINDINGS All analysed fractions showed reactivity with serum samples from patients with neuroangiostrongyliasis, especially female membrane alkaline (FAM) and female soluble alkaline (FAS) fractions together with female soluble saline (FSS), improving the technique specificity. MAIN CONCLUSIONS The results point to the possibility of use of raw female antigens in association with alkaline membrane antigens extracted from adult worms to aid in diagnosis and helps initiate neuroangiostrongyliasis surveillance and control actions.

Abdominal angiostrongyliasis in the Americas: fifty years since the discovery of a new metastrongylid species, Angiostrongylus costaricensis.

Angiostrongylus costaricensis is a zoonotic parasitic nematode described for the first time in 1971 by Pedro Morera and Rodolfo Céspedes in Costa Rica. This parasite causes an infection known as abdominal angiostrongyliasis, affecting mainly school-aged children and young adults. Infection with A. costaricensis has been associated with a myriad of rodent and mollusk species in the Americas and the Caribbean, as its natural hosts and reservoirs. In this commemorative review, we highlight the extensive research collected through a 50-year journey, which includes ecological, pathological, and molecular studies on A. costaricensis and its implicated disease. We also identify major knowledge gaps in its evolutionary history, the ecological role of imported and invasive mollusk species, and immune response. We propose that the advent of -omics analyses will allow us to gather novel information regarding A. costaricensis biology and infection dynamics, as well as to promote the design of much-needed sensitive and specific diagnostic tools.

De novo transcriptome reveals blood coagulation/antithrombin factors and infection mechanisms in Angiostrongylus cantonensis adult worms.

Angiostrongylus cantonensis is the main aetiological agent of eosinophilic meningoencephalitis in humans. Several outbreaks have been documented around the world, cementing its status as an emerging global public health concern. As a result, new strategies for the diagnosis, prophylaxis and treatment of cerebral angiostrongyliasis are urgently needed. In this study, we report on the de novo assembly of the A. cantonensis transcriptome, its full functional annotation and a reconstruction of complete metabolic pathways. All results are available at AngiostrongylusDB (http://angiostrongylus.lad.pucrs.br/admin/welcome). The aim of this study was to identify the active genes and metabolic pathways involved in the mechanisms of infection and survival inside Rattus norvegicus. Among 389 metabolic mapped pathways, the blood coagulation/antithrombin pathways of heparan sulphate/heparin are highlighted. Moreover, we identified genes codified to GP63 (leishmanolysin), CALR (calreticulin), ACE (peptidyl-dipeptidase A), myoglobin and vWD (von Willebrand factor type D domain protein) involved in the infection invasion and survival of the parasite. The large dataset of functional annotations provided and the full-length transcripts identified in this research may facilitate future functional genomics studies and provides a basis for the development of new techniques for the diagnosis, prevention and treatment of cerebral angiostrongyliasis.