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Nematodes of the genus Anisakis (Rhabditida, Anisakidae) are zoonotic fish-borne parasites and cause anisakiasis, a disease with mild to severe acute or chronic gastrointestinal and allergic symptoms and signs. Anisakiasis can potentially lead to misdiagnosis or delay in diagnosis, and it has been suggested as a risk factor for gastrointestinal tumors. Here, we describe a case report of a 25-year-old woman who presented with gastrointestinal (abdominal pain, nausea, diarrhea) and allergic (diffuse skin rash) symptoms and reported ingestion of raw fish contaminated by worms. Gastro and colon endoscopy allowed the visualization and removal of nematodes and collection of bioptic tissue from ulcers and polyps. The removed nematodes were molecularly identified as Anisakis pegreffii. The patient was treated with chlorphenamine maleate, betamethasone, omeprazole, paracetamol, albendazole. We conclude that an upper endoscopy matched with a colonoscopy and molecular characterization of the pathogen yields the most reliable diagnosis and treatment for human anisakiasis, enabling the complete removal of the larvae and preventing chronic inflammation and damage.

Infection with Blastocystis sp. has been reported in free-living and captive non-human primates (NHPs); however, surveys on Blastocystis sp. from north-western South America are scarce. This study aimed to identify Blastocystis sp. in free-ranging NHPs living in Colombia. A total of 212 faecal samples were collected from Ateles hybridus, Cebus versicolor, Alouatta seniculus, Aotus griseimembra, Sapajus apella, and Saimiri cassiquiarensis. Smears and flotation were used for morphological identification. For samples microscopically classified as positive for Blastocystis sp., we used conventional PCR to amplify and sequence two regions of the SSU rRNA gene and used Maximum Likelihood methods and Median Joining Network analyses for phylogenetic analyses. Via microscopy, 64 samples were Blastocystis sp. positive. Through molecular analyses, 18 sequences of Blastocystis sp. subtype 8 (ST8) were obtained. Strain and allele assignment together with a comparative phylogenetic approach confirmed that the sequences were ST8. Alleles 21, 156, and 157 were detected. Median Joining network analyses showed one highly frequent haplotype shared by specimens from Colombia and Peru and close relationships between haplotypes circulating in NHPs from Colombia, Ecuador, Brazil, and Mexico. This survey could support the elaboration of a more accurate epidemiological picture of the Blastocystis sp. infecting NHPs.

In this study, four dead great cormorant Phalacrocorax carbo sinensis (Blumenbach, 1978) specimens, collected from the coasts and lakes of Southern Italy, were examined by necropsy for the detection of Contraceacum sp. The adults and larvae found were subjected to morphological analysis and molecular identification by PCR-RFLP. A total of 181 Contracaecum specimens were detected in all of the four great cormorants examined (prevalence = 100%), showing an intensity of infestation between nine and ninety-two. A co-infestation by adult and larval forms of Contracaecum rudolphii was found only in one of the great cormorants examined. Following molecular investigations, 48 specimens of C. rudolphii A and 38 specimens of C. rudolphii B were detected, revealing co-infestation solely for the great cormorant from Leporano Bay (Southern Italy). Our results showed an opposite ratio between C. rudolphii A and C. rudolphii B in Pantelleria and in Salso Lake (Southern Italy) compared to what was reported in the literature, probably due to migratory stopovers and the ecology of the infested fish species, confirming the role of Contracaecum nematodes as ecological tags of their hosts.

Background: Anisakis spp. third-stage larvae (L3) are the causative agents of human zoonosis called anisakiasis. The accidental ingestion of L3 can cause acute and chronic inflammation at the gastric, intestinal, or ectopic levels. Despite its relevance in public health, studies on pathogenetic mechanisms and parasite-human interplay are scarce. The aim of this study was to investigate the human inflammatory response to different Anisakis vehicles of pathogenicity. Methods: Human colorectal adenocarcinoma (Caco-2) cells were exposed to Anisakis L3 (the initial contact with the host), extracellular vesicles (EVs, Anisakis–host communication), and crude extract (CE, the larval dying). The protein quantity and gene expression of two pro-inflammatory cytokines (IL-6 and IL-8) were investigated using an ELISA test (6 h and 24 h) and a qReal-Time PCR (1 h, 6 h, and 24 h), respectively. Results: The L3 and EVs induced a downregulation in both the Il-6 and Il-8 gene expression and protein quantity. On the contrary, the CE stimulated IL-6 gene expression and its protein release, not affecting IL-8. Conclusions: The Caco-2 cells seemed to not react to the exposure to the L3 and EVs, suggesting a parasite’s immunomodulating action to remain alive in an inhospitable niche. Conversely, the dying larva (CE) could induce strong activation of the immune strategy of the host that, in vivo, would lead to parasite expulsion, eosinophilia, and/or granuloma formation.

Anisakiasis is a zoonosis caused by the ingestion of raw or undercooked seafood infected with third-stage larvae (L3) of the marine nematode Anisakis. Based on L3 localization in human accidental hosts, gastric, intestinal or ectopic (extra-gastrointestinal) anisakiasis can occur, in association with mild to severe symptoms of an allergic nature. Given the increasing consumption of fish worldwide, the European Food Safety Authority declared Anisakis as an emerging pathogen. Despite its importance for public health and economy, the scientific literature is largely characterized by taxonomic, systematic and ecological studies, while investigations on clinical aspects, such as the inflammatory and immune response during anisakiasis, using a proper model that simulates the niche of infection are still very scarce. The aims of this review are to describe the clinical features of anisakiasis, to report the main evidence from the in vivo and in vitro studies carried out to date, highlighting limitations, and to propose future perspectives in the study field of anisakiasis.

The diversity, spread, and evolution of parasites in non-human primates (NHPs) is a relevant issue for human public health as well as for NHPs conservation. Although previous reviews have recorded information on parasites in NHPs (Platyrrhines) in the Americas, the increasing number of recent studies has made these inventories far from complete. Here, we summarize information about parasites recently reported in Platyrrhines, attempting to build on earlier reviews and identify information gaps. A systematic literature search was conducted in PubMed, ISI Web of Science, and Latin American and Caribbean Health Sciences Literature (LILACS), and following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Ninety-three studies were included after the screening process. Records for 20 genera of NHPs, including 90 species were found. Most of the studies were conducted on captive individuals (54.1%), and morphological approaches were the most used for parasite identification. The most commonly collected biological samples were blood and stool, and Protozoa was the most frequent parasite group found. There is still scarce (if any) information on the parasites associated to several Platyrrhine species, especially for free-ranging populations. The use of molecular identification methods can provide important contributions to the field of NHPs parasitology in the near future. Finally, the identification of parasites in NHPs populations will continue to provide relevant information in the context of pervasive habitat loss and fragmentation that should influence both human public health and wildlife conservation strategies.

Adult specimens of Trichuris sp. collected from crested porcupines (Hystrix cristata) from Italy were characterized using an integrative taxonomic approach involving morphological and molecular tools. The morphological features of this Trichuris sp. were compared to data already available for Trichuris spp. from Hystrix sp., revealing diagnostic traits, such as spicule length in males or vulva shape in females, which distinguish this Trichuris sp. from the other species. Evidence from sequences analysis of the partial mitochondrial COX1 region indicated that the taxon under study is a distinct lineage. Biometrical and genetic data suggested this Trichuris sp. to be a valid and separated taxon. However, since molecular data from other Trichuris spp. infecting Hystrix, such as T. infundibulus, T. hystricis, T. javanica, T.landak and T. lenkorani, are missing in public repositories, the number and identity of distinct lineages able to infect porcupines remain only partially defined.

Whipworms are parasitic intestinal nematodes infecting mammals, and traditionally humans and other primates that have so far been considered infected by Trichuris trichiura. Recent molecular studies report a more complex scenario suggesting the presence of a species complex with several Trichuris taxa specifically infecting only one primate species as well as taxa able to infect a range of primate species. The systematics of the group is important for taxonomic inference, to estimate the relative zoonotic potential, and for conservation purposes. In fact, captive animals living in zoological gardens are usually infected by persistent monoxenous intestinal parasites. Here, two Japanese macaques living in the Bioparco Zoological Garden of Rome were found infected by Trichuris sp. Nematodes were characterized at the molecular level using nuclear (btub and 18S) and mitochondrial (16S and cytb) markers and then compared to Trichuris collected previously in the same location, and to other Trichuris infecting primates. Evidences from mitochondrial and nuclear markers allowed for the identification of Trichuris sp. specific to Macaca fuscata. Results obtained here also described a uniform taxonomic unit of Trichuris, separated but closely related to Trichuris trichiura, thus, emphasizing its zoonotic potential for workers and visitors.