The aim of this review was to identify anti-inflammatory and antioxidant therapeutic agents and their effects on patients with chagasic myocarditis. A systematic review of the MEDLINE, EMBASE, WEB OF SCIENCE, SCOPUS, LILACS and CENTRAL databases (Cochrane Library) was carried out without language restrictions. The descriptors used were: ‘Chagas cardiomyopathy’, ‘treatment’, ‘Chagas disease’, ‘anti-inflammatory agents’, ‘Trypanosoma cruzi’ and ‘antioxidants’. A total of 4,138 articles was identified, six of which were selected for data extraction. Of these, four were related to antioxidant therapy with vitamins C and E supplementation, and two using anti-inflammatory therapy. The studies were carried out in Brazil and were published between 2002 and 2017. Antioxidant therapy with vitamin C and E supplementation increases the activity of antioxidant enzymes and reduces the oxidative markers. There is no conclusive data to support the use of vitamin supplementation and anti-inflammatory therapy in the treatment of chagasic cardiomyopathy. However, the studies indicate the possibility of vitamin supplementation as a new approach to the treatment of Chagas disease. Antioxidant therapy was proven to be a viable alternative for attenuating the oxidative damage caused by chronic chagasic cardiopathy, leading to a better prognosis for patients.

During three decades, only about 20 new drugs have been developed for malaria, tuberculosis and all neglected tropical diseases (NTDs). This critical situation was reached because NTDs represent only 10% of health research investments; however, they comprise about 90% of the global disease burden. Computational simulations applied in virtual screening (VS) strategies are very efficient tools to identify pharmacologically active compounds or new indications for drugs already administered for other diseases. One of the advantages of this approach is the low time-consuming and low-budget first stage, which filters for testing experimentally a group of candidate compounds with high chances of binding to the target and present trypanocidal activity. In this work, we review the most common VS strategies that have been used for the identification of new drugs with special emphasis on those applied to trypanosomiasis and leishmaniasis. Computational simulations based on the selected protein targets or their ligands are explained, including the method selection criteria, examples of successful VS campaigns applied to NTDs, a list of validated molecular targets for drug development and repositioned drugs for trypanosomatid-caused diseases. Thereby, here we present the state-of-the-art of VS and drug repurposing to conclude pointing out the future perspectives in the field.

Schistosoma mansoni is the most common species causing schistosomiasis. It has a complex life cycle involving a vertebrate definitive host and a snail intermediate host of the genus Biomphalaria. Each stage encounters a plethora of environmental stresses specially heat stress. Another sort of stress arises from repeated exposure of the parasite to praziquantel (PZQ), the only drug used for treatment, which leads to the development of resistance in the fields and the labs. Heat shock protein 70 (Hsp70) is found in different developmental stages of S. mansoni. It is immunogenic and regulate cercarial invasion besides its chaperone function. In the Biomphalaria/S. mansoni interaction, epigenetic modulations of the Hsp70 gene underscore the susceptibility phenotype of the snail. Hsp70 is up-regulated in adult S. mansoni with decreased sensitivity to PZQ. This could be due to the induction of oxidative and endoplasmic reticulum stress, induction of apoptosis, exposure to the stressful drug pressure and increase influx of calcium ions. Up-regulation of Hsp70 might help the worm to survive the schistosomicidal effect of the drug mainly by dealing with misfolded proteins, inhibition of apoptosis, induction of autophagy, up-regulation of the P-glycoprotein transporter and attenuation of the signalling from G protein coupled receptors.

The most deleterious stage of a trematode life cycle occurs in the first intermediate host where the parasite penetrates as a miracidium and asexually multiplicates in sporocysts or rediae. When infection advances, other organs can be occupied with severe effects on host individual health and population dynamics. Existing studies focused on these host/parasite systems are still scarce due to the usual low prevalence in ecosystems. Using cockles (Cerastoderma spp.) and two trematode species (Monorchis parvus and Gymnophallus choledochus) infecting these bivalves as first and second intermediate host, the present work aimed to (1) summarize the most relevant literature and (2) provide new information regarding this host/parasite system, taking advantage of a 21-year monthly database from Banc d'Arguin (France). This long-term monitoring showed that different trematode species display varying host size range preference (6–38 and 31–36 mm for M. parvus and G. choledochus, respectively). The occurrence of coinfection was lower than expected, raising some questions related to parasite interspecific competition. This review improved our understanding of the processes shaping the prevalence and distribution of parasitism. This study highlighted that beyond constant trematode assemblage monitoring, there is a need to identify the main predictors of rediae/sporocysts infection, such as the definitive host dynamics and miracidium infection processes, for future better management of host severe disease and mortality episodes.

Ascarid parasites infect a variety of hosts and regular anthelmintic treatment is recommended for all species. Parascaris spp. is the only ascarid species with widespread anthelmintic resistance, which allows for the study of resistance mechanisms. The purpose of this study was to establish an in vitro drug exposure protocol for adult anthelmintic-naïve Parascaris spp. and report a preliminary transcriptomic analysis in response to drug exposure. Live worms were harvested from foal necropsies and maintained in RPMI-1640 at 37 °C. Serial dilutions of oxibendazole (OBZ) and ivermectin (IVM) were prepared for in vitro drug exposure, and worm viability was monitored over time. In a second drug trial, worms were used for transcriptomic analysis. The final drug concentrations employed were OBZ at 40.1 μm (10 μg mL−1) and IVM at 1.1 μm (1 μg mL−1) for 24 and 3 h, respectively. The RNA-seq analysis revealed numerous differentially expressed genes, with some being potentially related to drug detoxification and regulatory mechanisms. This report provides a method for in vitro drug exposure and the phenotypic responses for Parascaris spp., which could be extrapolated to other ascarid parasites. Finally, it also provides preliminary transcriptomic data following drug exposure as a reference point for future studies of Parascaris spp.

The parasitic species of the Echinococcus granulosus sensu lato (sl) complex are the causative agents of cystic echinococcosis in humans. The lifecycle of E. granulosus sl is essentially domestic, and is based on the consumption by dogs of hydatid cysts in viscera of livestock species. The aim of this study was to survey E. granulosus sensu lato in livestock in France. A 1-year national survey of E. granulosus sl in livestock at the slaughterhouse was organized in 2012 in France, with systematic molecular confirmation. The prevalence of E. granulosus ss nationally was 0.002% in sheep, mainly focused in the Alpine area, and 0.001% in cattle, with the distribution of cases throughout the country. Echinococcus canadensis G6/7 was observed only in Corsica in pigs, with a prevalence of nearly 1% in the island. A national prevalence of 0.0002% was estimated for E. ortleppi in cattle, due to seven cases distributed in two foci. The results of this survey are of particular interest because of the zoonotic risk associated with the presence of these parasite species, for which systematic control at the slaughterhouse should enable their elimination.

Here we report on the infection of captive crested geckos Correlophus ciliatus Guichenot (Reptilia: Diplodactylidae), with adults of the ascaridoid nematode, Hexametra angusticaecoides Chabaud & Brygoo, 1960 (Ascarididae). A population of captive crested geckoes became ill and died within a short period of time. Nematodes were recovered from the crested geckoes examined from within the coelomic cavity, penetrating various organs and migrating through subcutaneous tissues, as well as emerging through the geckos' skin. One gecko was treated with levamisole following surgical excision of nematodes from under the skin; this gecko survived. The potential source of the nematode infection in the captive geckoes is discussed. It is most likely that wild-caught Madagascan mossy geckoes, Uroplatus sikorae Boettger (Reptilia: Gekkonidae), introduced the infection to the colony. Molecular sequences of the nematodes are the first produced for the members of this genus. A redescription of the species and its genetic characterization based on the internal transcribed spacer sequence data is provided, suggesting some of the morphological criteria that have been used in the past to distinguish between Hexametra spp. may have been intraspecific morphological variations.

The native rat lungworm (Angiostrongylus mackerrasae) and the invasive rat lungworm (Angiostrongylus cantonensis) occur in eastern Australia. The species identity of A. mackerrasae remained unquestioned until relatively recently, when compilation of mtDNA data indicated that A. mackerrasae sensu Aghazadeh et al. (2015b) clusters within A. cantonensis based on their mitochondrial genomes (mtDNA). To re-evaluate the species identity of A. mackerrasae, we sought material that would be morphologically conspecific with A. mackerrasae. We combined morphological and molecular approaches to confirm or refute the specific status of A. mackerrasae. Nematodes conspecific with A. mackerrasae from Rattus fuscipes and Rattus rattus were collected in Queensland, Australia. Morphologically identified A. mackerrasae voucher specimens were characterized using amplification of cox1 followed by the generation of reference complete mtDNA. The morphologically distinct A. cantonensis, A. mackerrasae and A. malaysiensis are genetically distinguishable forming a monophyletic mtDNA lineage. We conclude that A. mackerrasae sensu Aghazadeh et al. (2015b) is a misidentified specimen of A. cantonensis. The availability of the mtDNA genome of A. mackerrasae enables its unequivocal genetic identification and differentiation from other Angiostrongylus species.

The increase of contact between natural and rural areas is prominent in Brazil, due to agricultural activities and concern with the environmental conservation. In this context, domestic animals, wild fauna and humans are exposed to mutual exchange of parasites, microorganisms and diseases. We studied tick parasitism of wild carnivores and domestic dogs, and the environmental of questing ticks, in extensive cattle ranch areas intermingled with natural vegetation, and in a natural reserve, both in a region of Cerrado biome, Midwestern Brazil. From 2008 to 2015, we inspected 119 wild carnivores from nine species, and collected six tick species (Amblyomma sculptum, Amblyomma ovale, Amblyomma dubitatum, Amblyomma tigrinum, Dermacentor nitens and Rhipicephalus microplus). The most numerous and infested hosts were Cerdocyon thous, Lycalopex vetulus, Chrysocyon brachyurus, Puma concolor and Conepatus amazonicus. From 139 domestic dogs, we collected A. sculptum, Rhipicephalus sanguineus and R. microplus. From vegetation, samplings resulted in A. sculptum, A. dubitatum, A. ovale, Amblyomma rotundatum and R. microplus, with dominance of A. sculptum. Domestics and wild animals presented high overlapping of infestations by A. sculptum, a generalist and anthropophilic tick species. This tick is the most important vector of the Brazilian spotted fever, a lethal human disease. This fact elicits attention and requires efforts to monitor the presence of pathogens vectored by ticks circulating in this type of agroecosystem, including in other regions of the Brazil, because the most of the natural vegetation remaining have been increasingly immersed in pastures and agricultural matrix.

Cattle production in extensive systems favours the occurrence of gastrointestinal nematodes, and the use of nematophagous fungi complements the control strategies for these nematodes. The aim of this study was to evaluate the effectiveness of the fungi Arthrobotrys cladodes and Pochonia chlamydosporia in the biological control of gastrointestinal parasitic nematodes in grazing cattle. Twenty-four calves were randomly divided into four groups and allocated to independent paddocks from February 2018 to January 2019. In the first group, the animals received pellets containing P. chlamydosporia. In the second group, the animals received pellets containing A. cladodes. In the third group, the animals received pellets containing a combination of the fungi A. cladodes and P. chlamydosporia. In the control group, the animals received pellets without fungus. The combined use of A. cladodes and P. chlamydosporia showed greater efficacy in the biological control of bovine gastrointestinal parasitic nematodes than the same fungi used separately. The parasite load was lower and weight gain was greater (P ⩽ 0.05) in the groups of cattle treated with nematophagous fungi. Therefore, the use of A. cladodes and P. chlamydosporia is promising in the biological control of nematodiosis in cattle.

The spread of invasive, non-native species is a key threat to biodiversity. Parasites can play a significant role by influencing their invasive host's survival or behaviour, which can subsequently alter invasion dynamics. The North American signal crayfish (Pacifastacus leniusculus) is a known carrier of Aphanomyces astaci, an oomycete pathogen that is the causative agent of crayfish plague and fatal to European crayfish species, whereas North American species are considered to be largely resistant. There is some evidence, however, that North American species, can also succumb to crayfish plague, though how A. astaci affects such ‘reservoir hosts’ is rarely considered. Here, we tested the impact of A. astaci infection on signal crayfish, by assessing juvenile survival and adult behaviour following exposure to A. astaci zoospores. Juvenile signal crayfish suffered high mortality 4-weeks post-hatching, but not as older juveniles. Furthermore, adult signal crayfish with high-infection levels displayed altered behaviours, being less likely to leave the water, explore terrestrial areas and exhibit escape responses. Overall, we reveal that A. astaci infection affects signal crayfish to a much greater extent than previously considered, which may not only have direct consequences for invasions, but could substantially affect commercially harvested signal crayfish stocks worldwide.

Definitive diagnosis of hookworm infection is usually based on the microscopic detection of eggs in a stool sample; however, several cases display a low or irregular egg output. Serodiagnosis can be a useful tool to identify these cases, but conventional tests do not differentiate past from active infections. The aim of this study was to obtain and apply egg yolk polyclonal immunoglobulin (IgY) antibodies to detect immune complexes (ICs) in serum samples from patients infected with hookworm. Hens were immunized with Ancylostoma ceylanicum saline extract, their eggs were collected and then IgY antibodies were extracted and purified. Antibody purity was tested by 12% sodium dodecyl sulphate polyacrylamide gel electrophoresis and specificity was assessed by immunoblotting and immunofluorescence. IgY production was evaluated by kinetics enzyme-linked immunosorbent assay (ELISA). Sandwich ELISA tested the ability of IgY to detect ICs in serum samples, from which diagnostic parameters were calculated. Antibody responses increased steadily from day 7 to 42. In the immunoblotting assay, IgY recognized two protein complexes. The immunofluorescence assay showed no staining in control samples. The sandwich ELISA presented a very high diagnostic value, with a sensitivity of 90% and a specificity of 86.7%. Our pioneer strategy highlights the potential use of egg yolk IgY as a diagnostic test to detect active hookworm infection.

To model the colonization of a novel host by fleas, Synosternus cleopatrae and Xenopsylla ramesis, we established experimental lines maintained for 15 generations on a principal or a novel host (either co-occurring with a flea or not). We compared the blood meal size and the energy expended for digestion by fleas from the 15th generation of each line on these hosts between hosts within a line and between lines within a host asking (a) whether fleas adapt to a novel host (increased blood consumption/decreased energy expended for digestion); (b) if yes, whether this adaptation leads to the loss of ability to exploit an original host, and (c) whether the success of adaptation to a novel host depends on its ecological co-occurrence with a flea. The blood consumption and digestion energetics of fleas fed on the principal host differed from those on other hosts. The effect of the principal host on feeding performance differed between fleas, with S. cleopatrae consuming less blood and expending more energy for digestion on the principal than on any other host, whereas the opposite was true for X. ramesis. No changes in feeding performance on a novel host over generations were found. We propose several explanations for the lack of adaptation to a novel host over time. We explain the poor performance of S. cleopatrae on its principal host via its immune response mounting pattern. We argue that the principal host of a parasite is not necessarily the host on which the parasite demonstrates the best performance.