[Experimental study on the artificial infection of common freshwater snails with Angiostrongylus cantonensis in Dali Bai Autonomous Prefecture, Yunnan Province].

OBJECTIVE: To evaluate the potential risk of transmission of angiostrongyliasis by common freshwater snails in Dali Bai Autonomous Prefecture, Yunnan Province, so as to provide insights into local surveillance of angiostrongyliasis. METHODS: Common freshwater snails were collected from Dali Bai Autonomous Prefecture, Yunnan Province from March to April, 2020, and identified and bred in laboratory. SD rats were infected with third-stage larvae of Angiostrongylus cantonensis that were isolated from commercially available Pomacea canaliculata snails in Dali Bai Autonomous Prefecture, and freshwater snails were infected with the first-stage larvae of A. cantonensis that were isolated from the feces of SD rats 39 days post-infection at room temperature. The developmental process and morphological characteristics of worms in hosts were observed, and the percentages of A. cantonensis infections in different species of freshwater snails were calculated. Then, SD rats were infected with the third-stage larvae of A. cantonensis that were isolated from A. cantonensis-infected freshwater snails, and the larval development and reproduction was observed. RESULTS: More than 3 000 freshwater snail samples were collected from farmlands, ditches and wetlands around Erhai Lake in Dali Bai Autonomous Prefecture, and Cipangopaludina chinensis, P. canaliculata, Parafossarulus striatulus, Oncomelania hupensis robertsoni, Galba pervia, Physa acuta, Radix swinhoei, Assiminea spp., Tricula spp. and Bellamya spp. were morphologically identified. A total of 105 commercially available P. canaliculata snails were tested for A. cantonensis infections, and 2 P. canaliculata snails were found to be infected with A. cantonensis, in which the third-stage larvae of A. cantonensis were isolated. Ten species of freshwater snails were artificially infected with the third-stage larvae of A. cantonensis, and all 10 species of freshwater snails were found to be infected with A. cantonensis, with the highest positive rate of A. cantonensis infections in Bellamya spp. (62.3%, 137/204), and the lowest in C. chinensis (35.5%, 11/31). After SD rats were infected with the third-stage larvae of A. cantonensis isolated from different species of freshwater snails, mature adult worms of A. cantonensis were yielded. CONCLUSIONS: Multiple species of freshwater snails may serve as intermediate hosts of A. cantonensis under laboratory conditions in Dali Bai Autonomous Prefecture of Yunnan Province. Further investigations on natural infection of A. cantonensis in wild snails in Dali Bai Autonomous Prefecture seem justified.

A new diagnostic technique for identifying Angiostrongylus spp. larvae in intermediate snail species by examining the buccal cavity.

BACKGROUND: Angiostrongyliasis is a zoonotic parasitic disease caused by the rat lungworm Angiostrongylus cantonensis. The intermediate hosts of A. cantonensis are gastropods, and snail species such as Pomacea canaliculata play a key role in the transmission of human angiostrongyliasis. Detecting A. cantonensis infection in snails is an important component of epidemiological surveillance and the control of angiostrongyliasis. METHODS: In this study, a new method for diagnosing A. cantonensis infection in gastropods was developed by recovering larvae from the buccal cavity of three snail species. The entire buccal cavity of a snail was extracted, and the tissue was pressed between two microscope slides to observe whether A. cantonensis larvae were present. Our new method was compared with traditional pathogenic detection methods of lung microscopy, tissue homogenization, and artificial digestion. We artificially infected 160 P. canaliculata, 160 Cipangopaludina chinensis, and 160 Bellamya aeruginosa snails with A. cantonensis. Then, the four different detection methods were used to diagnose infection in each snail species at 7, 14, 21, and 28 days post exposure. RESULTS: We found no significant difference in the percentages of infected P. canaliculata snails using the four methods to detect A. cantonensis larvae. The radula pressing method had a mean detection rate of 80%, while the lung microscopy (81.3%), tissue homogenization (83.8%), and artificial digestion (85%) methods had slightly greater detection rates. Similarly, the percentages of infected C. chinensis snails that were detected using the radula pressing (80%), tissue homogenization (82.1%), and artificial digestion (83.8%) methods were not significantly different. Finally, the percentages of infected B. aeruginosa snails that were detected using the radula pressing (81.3%), tissue homogenization (81.9%), and artificial digestion (81.4%) methods were not significantly different. These results showed that the radula pressing method had a similar detection rate to traditional lung microscopy, tissue homogenization, or artificial digestion methods. CONCLUSIONS: This study demonstrates a new method for the qualitative screening of gastropods that act as intermediate hosts of A. cantonensis (and other Angiostrongylus species), provides technical support for the control of human angiostrongyliasis, and furthers research on A. cantonensis.

Detection of rat lungworm (Angiostrongylus cantonensis) infection by real-time PCR from the peripheral blood of animals: a preliminary study.

Rat lungworm disease or neuroangiostrongyliasis is a cerebral parasitic infection that affects humans and animals alike. Its clinical signs and symptoms can range from mild self-resolving to serious life-threatening conditions. Studies suggest therapeutic interventions during the early stages of infection to be more effective than in later stages. However, early diagnosis of infection is usually problematic without the knowledge of exposure and/or detection of the parasite's DNA or antibody against the parasite in the cerebrospinal fluid. This requires a lumbar puncture, which is an invasive procedure that generally requires hospitalization. This study evaluates an affordable and less invasive alternative to detect parasitic DNA by PCR from the peripheral blood of potentially infected animals. Blood samples from 58 animals (55 dogs and 3 cats) with clinical suspicion of infection were submitted to our lab between February 2019 and August 2022 by local, licensed veterinarians. DNA was extracted from whole blood, plasma, serum, and/or packed cells using the Qiagen DNeasy Blood & Tissue Kit as per the manufacturer's protocol. All 58 animals were tested by real-time PCR using the AcanITS1 assay and 32 of these animals (31dogs; 1 cat) were also tested using the AcanR3990 assay. The PCR results for both assays were classified into strongly positive > positive > weakly positive > negative, and equivocal for ambiguous results, based on the strength of the signal. The percent infection detected using the AcanITS1 and AcanR3990 assays was 12.72% (7/55) and 20.68% (6/29), respectively. The overall percent infection detected was 34.37% (11/32), with only two animals testing positive by both assays. The three cats involved in this study tested negative by both assays. These results are promising and warrant further investigations to increase sensitivity including variables that might affect detection in the blood, such as parasite load, and laboratory methodologies.

Local terrestrial snails as natural intermediate hosts of the zoonotic parasite Angiostrongylus cantonensis in the new European endemic area of Valencia, Spain.

AIM: The rat lungworm, Angiostrongylus cantonensis, has recently been found in the city of Valencia, parasitizing rats, Rattus norvegicus and Rattus rattus, its natural definitive hosts. This is the first finding of this zoonotic nematode in continental Europe. After informing local and national health authorities, the collection of local terrestrial snails took place with the aim of elucidating their potential role as intermediate hosts of A. cantonensis. METHODS AND RESULTS: A total of 145 terrestrial snails, belonging to the species Cernuella virgata, Cornu aspersum, Eobania vermiculata, Otala punctata, Pseudotachea splendida, Rumina decollata and Theba pisana, were randomly collected between May and December 2022 in public gardens, parks and orchards in six districts of Valencia, in five of which A. cantonensis had been reported previously in rats. Once collected and identified, the snails were frozen at -20°C. Subsequently, the DNA was isolated and screened by PCR using specific primers targeting the A. cantonensis COI gene. Seven individual snails, belonging to the species C. virgata, C. aspersum and T. pisana, were positive, for an overall prevalence of 4.8%. The PCR product from one of them was sequenced by Sanger sequencing. CONCLUSIONS: The three positive terrestrial snail species are among the edible species that are frequently included in various dishes in Spain. C. virgata is reported as a previously unrecorded intermediate host and should be added to the list of more than 200 species of terrestrial snails that have been reported worldwide as intermediate hosts of the rat lungworm. Considering that these terrestrial snails may release infective larvae of A. cantonensis on leafy green vegetables on which they feed and during their handling and preparation for consumption, prophylactic measures to prevent human neuroangiostrongyliasis in Valencia and other regions to which this zoonotic parasite may spread are recommended.

Autochthonous Angiostrongylus cantonensis, Angiostrongylus vasorum and Aelurostrongylus abstrusus infections in native terrestrial gastropods from the Macaronesian Archipelago of Spain.

The presence of zoonotic relevant Angiostrongylus cantonensis infections has recently been reported in rat final hosts and gastropod intermediate hosts in Tenerife, Spain. However, data on A. cantonensis, Angiostrongylus vasorum and Aelurostrongylus abstrusus prevalences in endemic gastropods for other islands of the Macaronesian Archipelago are still missing. In order to fill this gap, we conducted an epidemiological study on terrestrial native slug (Plutonia lamarckii) and snail (Cornu aspersum, Theba pisana, Rumina decollata) species in 27 selected locations of Tenerife, Gran Canaria, El Hierro, Lanzarote, La Palma and Fuerteventura. Overall, 131 terrestrial gastropods were collected in winter/spring season 2018/2019 and examined for the presence of metastrongyloid lungworm larvae via artificial digestion. The current data revealed a total prevalence of 4.6% for A. vasorum, 3.8% for A. abstrusus and 0.8% for A. cantonensis. In Tenerife, three lungworm species were detected, thereby re-confirming A. cantonensis endemicity for this island. Prevalences of snails (C. aspersum) originating from El Hierro were 5% for A. abstrusus and 15% for A. vasorum, respectively, with larval burdens up to 290 larvae per specimen. This epidemiological study indicates the presence of human, canine and feline lungworm species in Macaronesia, Spain. The current data-particularly those on anthropozoonotic A. cantonensis-call for a regular large-scale monitoring on intermediate hosts, paratenic hosts and definitive hosts to prevent further spread of lungworm-related diseases in humans and animals.

Angiostrongylus cantonensis in urban populations of terrestrial gastropods and rats in an impoverished region of Brazil.

The nematode Angiostrongylus cantonensis is the most common cause of neuroangiostrongyliasis (manifested as eosinophilic meningitis) in humans. Gastropod molluscs are used as intermediate hosts and rats of various species are definitive hosts of this parasite. In this study, we identified several environmental factors associated with the presence and abundance of terrestrial gastropods in an impoverished urban region in Brazil. We also found that body condition, age and presence of co-infection with other parasite species in urban Rattus norvegicus, as well as environmental factors were associated with the probability and intensity of A. cantonensis infection. The study area was also found to have a moderate prevalence of the nematode in rodents (33% of 168 individuals). Eight species of molluscs (577 individuals) were identified, four of which were positive for A. cantonensis. Our study indicates that the environmental conditions of poor urban areas (presence of running and standing water, sewage, humidity and accumulated rain and accumulation of construction materials) influenced both the distribution and abundance of terrestrial gastropods, as well as infected rats, contributing to the maintenance of the A. cantonensis transmission cycle in the area. Besides neuroangiostrongyliasis, the presence of these hosts may also contribute to susceptibility to other zoonoses.

Host snail species exhibit differential Angiostrongylus cantonensis prevalence and infection intensity across an environmental gradient.

Diverse snail species serve as intermediate hosts of the parasitic nematode Angiostrongylus cantonensis, the etiological agent of human neuroangiostrongyliasis. However, levels of A. cantonensis infection prevalence and intensity vary dramatically among these host species. Factors contributing to this variation are largely unknown. Environmental factors, such as precipitation and temperature, have been correlated with overall A. cantonensis infection levels in a locale, but the influence of environment on infection in individual snail species has not been addressed. We identified levels of A. cantonensis prevalence and intensity in 16 species of snails collected from 29 sites along an environmental gradient on the island of Oahu, Hawaii. The relationship between infection levels of individual species and their environment was evaluated using AIC model selection of Generalized Linear Mixed Models incorporating precipitation, temperature, and vegetation cover at each collection site. Our results indicate that different mechanisms drive parasite prevalence and intensity in the intermediate hosts. Overall, snails from rainy, cool, green sites had higher infection levels than snails from dry, hot sites with less green vegetation. Intensity increased at the same rate along the environmental gradient in all species, though at different levels, while the relation between prevalence and environmental variables depended on species. These results have implications for zoonotic transmission, as human infection is a function of infection in the intermediate hosts, ingestion of which is the main pathway of transmission. The probability of human infection is greater in locations with higher rainfall, lower temperature and more vegetation cover because of higher infection prevalence in the gastropod hosts, but this depends on the host species. Moreover, severity of neuroangiostrongyliasis symptoms is likely to be greater in locations with higher rainfall, lower temperature, and more vegetation because of the higher numbers of infectious larvae (infection intensity) in all infected snail species. This study highlights the variation of infection prevalence and intensity in individual gastropod species, the individualistic nature of interactions between host species and their environment, and the implications for human neuroangiostrongyliasis in different environments.

Development of a recombinase polymerase amplification (RPA-EXO) and lateral flow assay (RPA-LFA) based on the ITS1 gene for the detection of Angiostrongylus cantonensis in gastropod intermediate hosts.

Angiostrongylus cantonensis is a parasitic nematode known to infect humans through the ingestion of third stage larvae which can cause inflammation and damage to the central nervous system. Currently, polymerase chain reaction (PCR) is one of the most reliable diagnostic methods for detecting A. cantonensis in humans as well as in gastropod hosts, but requires expensive and specialized equipment. Here, we compare the sensitivity and accuracy of a recombinase polymerase amplification Exo (RPA-EXO) assay, and a recombinase polymerase amplification lateral flow assay (RPA-LFA) with a traditional quantitative PCR (qPCR) assay currently available. The three assays were used to test 35 slugs from Hawai'i for the presence of A. cantonensis DNA. Consistent results among the three tests were shown in 23/35 samples (65.7%), while 7/35 (20%) were discordant in low infection level samples (<0.01 larvae per mg tissue), and 5/35 (14.3%) were equivocal. To evaluate sensitivity, a partial ITS1 gene was cloned, and serial plasmid dilutions were created ranging from 100 copies µL-1 to ~1 copy µL-1. All three assays consistently detected 50-100 copies µL-1 in triplicate and qPCR was able to detect ~13 copies µL-1 in triplicate. RPA-EXO was able to detect 25 copies µL-1 in triplicate and RPA-LFA was not able to amplify consistently below 50 copies µL-1. Thus, our RPA-EXO and RPA-LFA assays do not appear as sensitive as the current qPCR assay at low DNA concentrations; however, these tests have numerous advantages that may make them useful alternatives to qPCR.

Further studies of neuroangiostrongyliasis (rat lungworm disease) in Australian dogs: 92 new cases (2010-2020) and results for a novel, highly sensitive qPCR assay.

The principal aim of this study was to optimize the diagnosis of canine neuroangiostrongyliasis (NA). In total, 92 cases were seen between 2010 and 2020. Dogs were aged from 7 weeks to 14 years (median 5 months), with 73/90 (81%) less than 6 months and 1.7 times as many males as females. The disease became more common over the study period. Most cases (86%) were seen between March and July. Cerebrospinal fluid (CSF) was obtained from the cisterna magna in 77 dogs, the lumbar cistern in f5, and both sites in 3. Nucleated cell counts for 84 specimens ranged from 1 to 146 150 cells µL-1 (median 4500). Percentage eosinophils varied from 0 to 98% (median 83%). When both cisternal and lumbar CSF were collected, inflammation was more severe caudally. Seventy-three CSF specimens were subjected to enzyme-linked immunosorbent assay (ELISA) testing for antibodies against A. cantonensis; 61 (84%) tested positive, titres ranging from <100 to ⩾12 800 (median 1600). Sixty-one CSF specimens were subjected to real-time quantitative polymerase chain reaction (qPCR) testing using a new protocol targeting a bioinformatically-informed repetitive genetic target; 53/61 samples (87%) tested positive, CT values ranging from 23.4 to 39.5 (median 30.0). For 57 dogs, it was possible to compare CSF ELISA serology and qPCR. ELISA and qPCR were both positive in 40 dogs, in 5 dogs the ELISA was positive while the qPCR was negative, in 9 dogs the qPCR was positive but the ELISA was negative, while in 3 dogs both the ELISA and qPCR were negative. NA is an emerging infectious disease of dogs in Sydney, Australia.

Angiostrongylosis meningomyelitis without blood eosinophilia.

Angiostrongylus cantonensis and Gnathostoma spinigerum usually cause eosinophilic meningitis with associated peripheral blood eosinophilia. A 44-year-old man developed acute paraplegia with bowel and bladder dysfunction. Spinal magnetic resonance images showed a long T2W hyperintensity signal from the 1st to 8th spinal thoracic level. Cerebrospinal fluid analysis revealed eosinophilia and elevated cerebrospinal fluid protein, whereas differential leucocytes count in peripheral blood was unremarkable. Positive immunoblot tests for A. cantonensis antibody in serum and cerebrospinal fluid were reported. The patient had neither history of recent traveling to the high endemic areas of the parasite in Thailand, nor consumption the parasitic hosts. Immediate treatment with intravenous pulse methylprednisolone and oral albendazole resulted in complete recovery. Despite an unremarkable differential leucocytes count, absence a history of parasitic hosts consumption, and a less common presentation with meningomyelitis, A. cantonensis should be considered when cerebrospinal fluid eosinophilia presents.

Sandwich dot-immunogold filtration assay (DIGFA) for specific immunodiagnosis of active neuroangiostrongyliasis.

Serological tests may yield false-negative results for specific antibodies detection before or at the early seroconversion phase. Tests that detect circulating antigens of Angiostrongylus cantonensis would therefore be of value in diagnosis to distinguish current or past infection. Here, a quick, easy to perform, portable and inexpensive diagnostic device for detection of 31-kDa A. cantonensis specific antigens had been developed. This sandwich dot-immunogold filtration assay (AcDIGFAAg), for detecting active angiostrongyliasis was produced using anti-A. cantonensis polyclonal antibody dotted on the nitrocellulose membrane as a capture agent and colloidal gold-labelled anti-31 kDa A. cantonensis antibody as a detection agent. A well-defined pink dot, indicating positivity, was seen readily by naked eye within 10-15 min. The AcDIGFAAg detected A. cantonensis-specific antigens in cerebrospinal fluid samples from 4 out of 10 serologically confirmed angiostrongyliasis cases and 2 out of 5 suspected cases with negative anti-A. cantonensis antibodies. Among the 19 patient sera with A. cantonensis infection, 2 showed positive reaction by AcDIGFAAg. No positive AcDIGFAAg reaction was observed in all the serum samples with other parasitic diseases, and the healthy controls. The present 'AcDIGFAAg' enables rapid qualitative detection of the specific 31-kDa antigens of A. cantonensis in clinical samples with potential for application even under resource-limited settings.

Angiostrongylus cantonensis (rat lungworm) in Florida, USA: current status.

Angiostrongylus cantonensis has been found in Florida, USA, from the panhandle in the north to Miami and surrounding areas in the southern parts of the state, in both definitive and intermediate hosts in a limited studies completed in 2015. Additional studies have identified this parasite in a variety of intermediate hosts, both native and non-native gastropod species, with new host species recorded. Many areas in Florida with higher A. cantonensis prevalence were those with a high human population density, which suggests it is a matter of time before human infections occur in Florida. Case reports in the state currently involve non-human primates and include a gibbon and orangutan in Miami. Here, we report the current status of A. cantonensis in the state, as well as the infection in a capuchin monkey and presumptive infection in a red ruffed lemur in Gainesville, Florida.

Meningitis patients with Angiostrongylus cantonensis may present without eosinophilia in the cerebrospinal fluid in northern Vietnam.

BACKGROUND: Eosinophilic meningitis (EM) is a rare clinical syndrome caused by both infectious and noninfectious diseases. In tropical pacific countries, Angiostrongylus cantonensis is the most common cause. However, the EM definition varies in the literature, and its relation to parasitic meningitis (PM) remains unclear. METHODOLOGY/PRINCIPAL FINDINGS: Adult and adolescent patients of 13 years old or above with suspected central nervous system (CNS) infections with abnormal CSF findings were prospectively enrolled at a tertiary referral hospital in Hanoi, Vietnam from June 2012 to May 2014. Patients with EM or suspected PM (EM/PM) were defined by the presence of either ≥10% eosinophils or an absolute eosinophil cell counts of ≥10/mm3 in the CSF or blood eosinophilia (>16% of WBCs) without CSF eosinophils. In total 679 patients were enrolled: 7 (1.03%) had ≥10% CSF eosinophilia, 20 (2.95%) had ≥10/mm3 CSF eosinophilia, and 7 (1.03%) had >16% blood eosinophilia. The patients with ≥10% CSF eosinophilia were significantly younger (p = 0.017), had a lower body temperature (p = 0.036) than patients with ≥10/mm3 CSF eosinophilia among whom bacterial pathogens were detected in 72.2% (13/18) of those who were tested by culture and/or PCR. In contrast, the characteristics of the patients with >16% blood eosinophilia resembled those of patients with ≥10% CSF eosinophilia. We further conducted serological tests and real-time PCR to identify A. cantonensis. Serology or real-time PCR was positive in 3 (42.8%) patients with ≥10% CSF eosinophilia and 6 (85.7%) patients with >16% blood eosinophilia without CSF eosinophils but none of patients with ≥10/mm3 CSF eosinophilia. CONCLUSIONS: The etiology of PM in northern Vietnam is A. cantonensis. The eosinophil percentage is a more reliable predictor of parasitic EM than absolute eosinophil count in the CSF. Patients with PM may present with a high percentage of eosinophils in the peripheral blood but not in the CSF.

Zoonotic Helminthiases in Rodents (Bandicota indica, Bandicota savilei, and Leopoldamys edwardsi) from Vientiane Capital, Lao PDR.

Zoonotic helminths of three rodent species, Bandicota indiaca, Bandicota savilei, and Leopoldamys edwardsi, were investigated in Vientiane capital, Lao PDR. A total of 310 rodents were infected with 11 species of helminth parasites. There were 168 (54.2%) of 310 rodents infected with zoonotic helminths. From our results, there are six recorded zoonotic helminth species, and the highest prevalence was exhibited by Raillietina sp. (30.7%), followed by Hymenolepis diminuta (17.7%), Hymenolepis nana (2.6%), Echinostoma ilocanum (1.9%), Echinostoma malayanum (1.3%), and Angiostrongylus cantonensis (1%). This is the first study of zoonotic helminths in L. edwardsi and the first report of H. diminuta, H. nana, E. ilocanum, and E. malayanum in Bandicota indica and B. savilei, and the first demonstration of A. cantonenensis in B. indica in Lao PDR. From our results, these three rodents are potentially important reservoir hosts of zoonotic helminths. Thus, effective control programs should be considered for implementation to prevent the transmission of these zoonoses in this area.

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.

Mollusk microbiota shift during Angiostrongylus cantonensis infection in the freshwater snail Biomphalaria glabrata and the terrestrial slug Phillocaulis soleiformis.

In the present work, we reported for the first time the microbiome from Phyllocaulis soleiformis and Biomphalaria glabrata assessed using high-throughput DNA sequencing pre- and post-infection with the helminth parasite Angiostrongylus cantonensis. B. glabrata and P. soleiformis were experimentally infected with A. cantonensis. Fecal DNAs from control and infected groups were extracted and subjected to 16S rRNA high-throughput sequencing survey. No significant differences were found in the alpha diversity indexes in Phyllocaulis and Biomphalaria experiments independently. PCoA analysis using the unweighted UniFrac measures showed that both microbiotas behaved differently depending on the host. In Biomphalaria microbiota, control and infected groups were significantly different (p = 0.0219), while Phyllocaulis samples were not (p = 0.5190). The microbiome of P. soleiformis infected with A. cantonensis showed a significant decrease of Sphingobacterium and a substantial increase of Cellvibrio when compared to a control group. The microbiome of B. glabrata infected with A. cantonensis showed a significant decline in the abundance of Flavobacterium, Fluviicola, Nitrospira, Vogesella and an OTU belonging to the family Comamonadaceae, and a significant increase of Uliginosibacterium and an OTU belonging to the family Weeksellaceae when compared to a control group. Overall, the microbiome data reported here provided valuable information with regard to the diversity of bacterial communities that comprise the gut microbiome of gastropods. Furthermore, we report here the effect of the infection of the helminth A. cantonensis in the ratio and distribution of the fecal microbiome of the snails. Further studies are highly valuable in order to better understand those interactions by comparing different microbiome profiles and mollusk models. By now, we anticipate that ecological studies will take significant advantage of these advances, particularly concerning improving our understanding of helminth-microbiome-host interactions.

Eosinophilic meningitis outbreak related to religious practice.

Three patients with eosinophilic meningitis (EoM) were investigated in two hospitals in Porto Alegre, Southern Brazil. These patients had a common exposure after the ingestion of raw mollusks in a religious ritual. Two of them had an uncommon presentation with intense lower distal extremities pain and small fiber neuropathy as defined by an electroneuromyography (ENMG) study. All three patients were positive for Angiostrongylus cantonensis serology and recovered after antihelminthic and anti-inflammatory treatment. Increased awareness of A. cantonensis infection is important to avoid new infections and to improved recognition and handling of cerebral angiostrongyliasis.

Case Report: Angiostrongylus cantonensis Meningoencephalitis in a 9-Month-Old Baby in Vietnam.

Meningoencephalitis is not a rare disease in small children. However, eosinophilic meningitis due to Angiostrongylus cantonensis is unusual in a baby. We describe the case of a 9-month-old baby from North Vietnam with eosinophilic meningoencephalitis. The baby lived in a rural area, where farming is widespread, and presented with fever and seizures. Laboratory results showed peripheral eosinophilia (16.1%), cerebrospinal fluid (CSF) white blood cell count 220/mm3 (26% eosinophils), CSF antibody test positive for Ascaris, CSF ELISA positive for Angiostrongylus cantonensis, and blood ELISA positive for A. cantonensis. A mobile worm was identified in the CSF. The presentation was consistent with a diagnosis of A. cantonensis eosinophilic meningitis. The baby recovered fully after administering albendazole (200 mg/day for 2 weeks), and intravenous dexamethasone (0.6 mg/kg/day every 8 hours) and mannitol (1.5 g/kg/day every 8 hours) for the first 3 days, followed by 5 days of oral prednisolone (2 mg/kg/day).

First cases of Angiostrongylus cantonensis infection reported in Martinique, 2002-2017.

Neuroangiostrongyliasis is a parasitic disease caused by the accidental ingestion of the nematode Angiostrongylus cantonensis in its larval form. Human infection can lead to eosinophilic meningitis, sometimes complicated by life-threatening radiculomyelitis or encephalitis. Although some cases have been reported from other Caribbean Islands, no cases have been diagnosed in Martinique so far. Here, we report the first eight laboratory-confirmed cases of neuroangiostrongyliasis on the island of Martinique, French West Indies, between 1 January 2002 and 31 December 2017. One case was fatal and five resulted in neurological sequelae. The medical community should consider the risk of A. cantonensis infection in patients living in or returning from Martinique.

TITLE: Premiers cas d'angiostrongylose à Angiostrongylus cantonensis à la Martinique, de 2002 à 2017. ABSTRACT: L'angiostrongylose neuroméningée est une maladie parasitaire causée par l'ingestion accidentelle du nématode Angiostrongylus cantonensis sous sa forme larvaire. L'infection humaine peut conduire à une méningite à éosinophiles, pouvant évoluer en radiculomyélite ou encéphalite menaçant le pronostic vital. Bien que des cas aient été rapportés dans d'autres îles des Caraïbes, aucun cas n'avait été diagnostiqué à la Martinique jusqu'à présent. Dans cet article, nous caractérisons les huit premiers cas d'angiostrongylose neuroméningée biologiquement diagnostiqués à la Martinique, Antilles françaises, entre le 1er janvier 2002 et le 31 décembre 2017. Un cas s'est révélé mortel et cinq ont engendré des séquelles neurologiques. La communauté médicale doit désormais considérer le risque d'infection à A. cantonensis chez les patients vivant ou revenant d'un voyage à la Martinique.

Angiostrongylus cantonensis central nervous system infection in captive callitrichids in Texas.

Angiostrongylus cantonensis is a tropical lungworm of rats known for central nervous system migration in aberrant primate hosts. Here, we describe A. cantonensis infection in three captive callitrichids from a Texas zoo. The affected animals included a Goeldi's monkey (Callimico goeldii), a cotton-top tamarin (Saguinus oedipus), and a pied tamarin (Saguinus bicolor) that ranged from 8 to 18 years old. Clinical signs included lethargy, ataxia, and seizures. Histologically, these animals had an eosinophilic meningoencephalitis to myelitis and some areas had abundant macrophages and parasite migration tracts. All cases had intralesional metastrongyle parasites, and nematodes were extracted from the formalin-fixed brain specimen in one case. This extracted parasite was identified as Angiostrongylus cantonensis based on morphologic features and diagnosis was confirmed with PCR. These cases represent the first report of this parasite in non-human primates in Texas, highlighting the western spread of A. cantonensis in the continental United States.