Little is known about the efficacy of cysteine proteinases (CP) as anthelmintics for cestode infections in vivo. Hymenolepis microstoma is a natural parasite of house mice, and provides a convenient model system for the assessment of novel drugs for anthelmintic activity against cestodes. The experiments described in this paper indicate that treatment of H. microstoma infections in mice with the supernatant of papaya latex (PLS), containing active cysteine proteinases, is only minimally efficacious. The statistically significant effects seen on worm burden and biomass showed little evidence of dose dependency, were temporary and the role of cysteine proteinases as the active principles in PLS was not confirmed by specific inhibition with E-64. Worm fecundity was not affected by treatment at the doses used. We conclude also that this in vivo host–parasite system is not sensitive enough to be used reliably for the detection of cestocidal activity of compounds being screened as potential, novel anthelmintics.

The composition and diversity of parasite communities and intestinal components, as well as infra-community structure, were assessed in eels Anguilla anguilla, from Mar Menor, a permanent Mediterranean hypersaline coastal lagoon. Data were used to determine whether this helminth community differs in composition and structure from that of eels in lagoons with lower salinity regimes and higher freshwater inputs. A total prevalence of 93% was detected. Specifically, parasites were identified as Deropristis inflata, Bucephalus anguillae, Contracaecum sp., Anguillicoloides crassus and two plerocercoid larvae belonging to the order Proteocephalidae, the marine species representing 91% of the isolated helminths. In the total community, digenetic trematodes were the dominant group of helminths, and D. inflata, an eel specialist, dominated both the component community and the infra-community. Richness and diversity were low but similar to those reported in other saline lagoons, and maximum species per eel did not exceed four. At the infra-community level, higher abundance than in other brackish or marine Mediterranean environments was detected. The findings provide further evidence of the similarity in composition and structure of helminth communities in eels from various Mediterranean coastal lagoons. Moreover, salinity-dependent specificities are well supported and reflect the life history of individual eels.

Toxocara canis and Toxocara cati are nematode parasites in dogs and cats, respectively, transmitted by ingestion of embryonated eggs, transmammary and transplacental (T. canis) routes and paratenic host predation. Many parasites use mechanisms that change the behaviour of their hosts to ensure continued transmission. Several researchers have demonstrated behavioural changes in mouse models as paratenic hosts for T. canis. However, there have been no studies on behavioural changes in laboratory rats (Rattus norvegicus) experimentally infected with T. cati. This study investigated behavioural changes and muscle strength in male and female rats experimentally infected with T. cati or T. canis in acute and chronic phases of infection. Regardless of sex, rats infected with T. cati showed a greater decrease in muscle strength 42 days post infection compared to rats infected with T. canis. However, behavioural changes were only observed in female rats infected with T. canis.

One of the fish species with the highest potential for aquaculture is the sharpsnout seabream, Diplodus puntazzo Cetti. Among other aspects, the development of new fish cultures requires studies of potential pathogens that may compromise survival of the fish in captivity. Moreover, both cultured and wild fish can act as sources or reservoirs of pathogens which may negatively affect other well-established cultures. We have studied the parasite fauna of the wild sharpsnout seabream, and monitored the survival of the parasites in culture conditions. The sharpsnout seabream was sampled from two different Spanish localities and examined for parasites. Additionally, 20 fish were maintained in captivity. Ten of them were examined for parasites after a period of 10 days and a further ten fish after another 10 days. All fish were parasitized with at least four species, with 19 parasite species being identified, seven of which were recorded for the first time in the sharpsnout seabream. These included Microcotyle sp., Magnibursatus bartolii, Steringotrema pagelli, Galactosomum sp., Cardiocephaloides longicollis, Caligus ligusticus and Gnathia vorax. We also report the first records of two parasite species in the wild sharpsnout seabream, the polyopisthocotylean monogeneans Atrispinum seminalis and Sparicotyle chrysophrii. Previously, these parasites had only been recorded in farmed sharpsnout seabream. Most parasites in the skin, gills and alimentary tract disappeared under the conditions of captivity, with the exception of the monogeneans of the genus Lamellodiscus. The information provided about the sharpsnout seabream parasite fauna will be useful to prevent possible problems in fish farms due to some parasite species. Many parasites of the sharpsnout seabream recorded in the present study are shared by the main fish species in Mediterranean aquaculture, the gilthead seabream, thus suggesting the possibility of cross-infections.

Experimental infections of Galba sp. (origin, Colombia) with allopatric isolates of Fasciola hepatica from France or Fascioloides magna from the Czech Republic were carried out during five successive snail generations to determine if this lymnaeid might sustain complete larval development of either parasite. In snails exposed to F. hepatica, 7 of 400 snails harboured several rediae and only two snails contained a small number of free cercariae on day 50 post-exposure. In contrast, the intensity of F. magna infection in Galba sp. progressively increased from the F1 to F5 generations. Spontaneous cercarial shedding of F. magna occurred in 7 of 100 Galba sp. belonging to the F5 generation and the number of shed cercariae did not differ significantly from that noted in control Galba truncatula of French origin. Galba sp. from Colombia can be added to the list of potential intermediate hosts for F. magna.

Because of the natural adaptation of Mexican sheep, the aim of the present study was to identify the presence or absence of gastrointestinal parasitic nematodes (GIN) resistant to benzimidazole (BZ) in both Chiapas and Pelibuey sheep breeds on local farms. Both male and female GIN-infected grazing sheep of the two breeds were selected. Sheep faecal samples were collected to obtain infective larvae (L3). This evolving stage of the parasite was used for taxonomic identification of the genus, based on its morphological characteristics. BZ anthelmintic resistance was evaluated using a nematode–compound in vitro interaction bioassay and the allele-specific polymerase chain reaction technique to detect mutations of residues 198 and 200 on isotype 1 of the β-tubulin gene. Three BZ-based compounds (febendazole (FBZ), tiabendazole (TBZ) and albendazole (ABZ)) at concentrations of 1, 0.5, 0.25, 0.125, 0.062 and 0.03 mg/ml were used to estimate the anthelmintic efficacy and lethal dose (LD50, LD90 and LD99) of the drugs. Two parasitic nematodes, Haemonchus and Teladorsagia, were identified in both isolates. Also, the proportions of anthelmintic resistance identified in GIN of the two sheep breeds were 68% in isolates from the Chiapas breed and 71.8% in the Pelibuey breed. The specific lethal activity obtained with FBZ was higher than 90%. However, TBZ and ABZ showed a lethal activity lower than 50%. High variability in the discriminating dose values was found among the BZ drugs. For example, FBZ LD ranged from 0.01 to 1.20 mg/ml; on the other hand, TBZ and ABZ required a dose ranging from 0.178 to 759 mg/ml. In addition, amino acid changes of Phe (TTC) to Tyr (TAC) at codon 200 of the β-tubulin gene, showing resistance to BZ, and no changes at codon 198 Glu (GAA) to Ala (GCA) were observed for both isolates. These results confirmed the presence of a genetic mutation associated with BZ in both Chiapas and Pelibuey nematode isolates.

Human taeniosis due to Taenia saginata is cosmopolitan where beef is consumed; however, there is little or no information on the symptomatology over the early time-course of human infection. Copro-antigen detection is very useful in community screening for human taeniosis, particularly for T. solium, but there are no data on copro-antigen detection in pre-patent infection. In order to provide insight into this, a voluntary self-infection with T. saginata was undertaken and monitored over a 6-month period using a copro-antigen enzyme-linked immunosorbent assay (ELISA) that we developed using anti-T. saginata antibody based reagents. Tapeworm patency, defined as first proglottid appearance, occurred on day 86 post-infection (pi) and was followed by almost daily release of proglottids (range 1–8) until termination using praziquantel on day 180 pi. The first 10 weeks post-infection (wpi) were essentially asymptomatic, followed by main symptoms of involuntary proglottid discharge throughout the infection period, and abdominal discomfort peaking around 15–19 wpi. Copro-antigens could not be reliably detected until 2 weeks before proglottid patency but then remained highly elevated over the next 15 weeks until treatment. Copro-antigen levels reverted to negative 4 days post-treatment. This time-course study suggests that although copro-antigen ELISA is an excellent diagnostic tool for established patent infections of T. saginata, it may not be reliable for faecal antigen detection in the early infection phase prior to proglottid release for T. saginata and other human taenioses.

Serological diagnosis of cystic echinococcosis (CE) is usually made by detecting specific antibodies in serum samples. However, collection of blood samples is difficult and may be hazardous and unsafe. Thus, it is important to assess alternative simple methods of sampling body fluids that give similar results. Saliva and urine have been suggested as possible alternatives to detect specific antibodies for the diagnosis of various diseases. To the best of our knowledge, there has been no previously published study regarding the detection of CE-specific immunoglobulin (Ig) G subclass antibodies (IgG1–4) in urine. Therefore, the present study was designed to assess the value of hydatid-specific antibodies of IgG, IgM, IgE and IgG subclass in urine and serum samples for the diagnosis of CE. Serum and urine samples of 41 surgically confirmed patients of CE, 40 patients with other diseases and 16 healthy subjects were included in the study. CE-specific total IgG, IgE and IgG4 in sera and total IgG, IgG4 and IgG1 in the urine of CE patients were the most important specific antibodies for the diagnosis of CE. However, total IgG usually persists for an extended period and has a very high cross-reactivity. The diagnostic sensitivity of hydatid-specific IgM in serum and urine samples was very low and therefore cannot be used as a diagnostic marker. There was no significant difference between IgG1 and IgG4 in serum and urine and both showed the best correlation for the diagnosis of CE. These considerations suggest that detection of antibodies in urine could provide a new approach in the diagnosis of CE.

A total of 195 Epinephelus coioides (Hamilton, 1822) were studied for fish parasites from Javanese (Segara Anakan lagoon) and Balinese waters. Up to 25 different parasite species belonging to the following taxa: one Ciliata, one Microsporea, five Digenea, one Monogenea, four Cestoda, four Nematoda, one Acanthocephala, one Hirudinea and seven Crustacea were identified with four new host and locality records. The dominant parasites included the monogenean Pseudorhabdosynochus lantauensis (53.3–97.1%), the nematode Spirophilometra endangae (23.3–42.9%), the digenean Didymodiclinus sp. (2.9–40.0%), the nematodes Philometra sp. (22.6–34.3%) and Raphidascaris sp. (2.9–28.6%), and the isopod Alcirona sp. (6.7–31.4%). Regional differences for E. coioides were found in terms of endoparasite diversity, total diversity according to Shannon–Wiener, Simpson index and Evenness. A comparison with published data from Sumatera revealed highest endoparasite diversity (Shannon–Wiener: 1.86/1.67–2.04) and lowest ectoparasite/endoparasite ratio (0.73/0.57–0.88) off the Balinese coast, followed by Lampung Bay, Sumatera (1.84; 0.67), off the coast of Segara Anakan lagoon (1.71; 0.71), and in the lagoon (0.30/0.19–0.66; 0.85/0.67–1.00). The presented data demonstrate the natural range of these parameters and parasite prevalences according to habitat and region, allowing adjustment of the scale that has been used in the visual integration of the parasite parameters into a star graph. The parasite fauna of E. coioides in Segara Anakan lagoon ‘improved’ from 2004 until 2008/09, possibly related to earlier oil spill events in 2002 and 2004. The use of grouper fish parasites as an early warning system for environmental change in Indonesian coastal ecosystems is discussed.

The helminth fauna of the wood mouse, Apodemus sylvaticus, in the Erro River valley (Navarre, Spain) was investigated from a total of 150 mice between February 2001 and July 2002. An overall prevalence of 90.7% was recorded and up to 14 helminth species identified. The most prevalent species was the nematode Heligmosomoidespolygyrus (78.0%), whereas Syphacia stroma was the species with the highest median abundance (19.8). The detection of Calodium hepaticum, Rodentolepis straminea and the larvae of Hydatigera taeniaeformis are significant, since these helminth species could be considered potential human parasites. The helminth infracommunity comprised no more than five species. A significant predominance of monoxenous species was detected. Statistically significant differences were also found between prevalences, helminth abundance, species richness and helminth diversity of sub-populations of the wood mouse determined by host age and season of capture, which agree with most of the studies carried out on this host. This study will shed light on the helminth community of the wood mouse from a region of Spain which has not previously been documented.

Lymphatic filariasis is a parasitic disease of tropical countries. This is a disfiguring and painful disease contracted in childhood, but the symptoms become apparent only in later years. Diagnosis of filarial infection is very crucial for the management of the disease. The main objective of this study was to develop a filarial antigen-based immunological assay for the diagnosis and surveillance of the disease. Monoclonal and polyclonal antibodies were raised to the recombinant protein Brugia malayi vespid allergen homologue (VAH). Capture enzyme-linked immunosorbent assay (ELISA) was standardized utilizing various combinations of antibodies and evaluated with serum samples of endemic normal (EN, n= 110), microfilaraemic (MF, n= 65), chronic pathology (CP, n= 45) and non-endemic normal (NEN, n= 10) individuals. Of the 230 samples tested, VAH capture assay detected circulating antigen in 97.91% of bancroftian and 100% of brugian microfilaraemic individuals, and 5% of endemic normal individuals, comparable to the earlier reported SXP-1 antigen detection assay. However, the combination of VAH and SXP-1 (VS) capture ELISA was found to be more robust, detecting 100% of microfilaraemic individuals and with higher binding values. Thus an antigen capture immunoassay has been developed, which can differentiate active infection from chronic infection by detecting circulating filarial antigens in clinical groups of endemic areas.

The aim of this study was to investigate the effect of hydatid cysts and microbial agents on the acute-phase response in cattle. Twenty-seven cattle with hydatid cysts and eight apparently healthy cattle comprised the study and control groups, respectively. Parasitological, microbiological, histopathological and immunohistochemical examinations of the liver and lungs were undertaken, and 49 of these organs were infected with cysts. In 14 of 31 (45.1%) livers and 10 of 18 (55.5%) lungs microbial growth was observed. The most frequent species occurring in the liver were Staphylococcus aureus, Escherichia coli, Corynebacterium spp. and Campylobacter spp., whereas in the lungs the most common species was Candida spp., followed by Streptococcus spp., Mannheimia haemolytica, Corynebacterium spp., Micrococcus spp. and S. aureus. The concentration of serum interleukin (IL-6) in infected cattle, 455.35 ± 39.68 pg/ml, was significantly higher than that of 83.02 ± 17.87 pg/ml in the control group (P< 0.001). The serum amyloid A (SAA) level of infected cattle was 7.51 ± 0.41 μg/ml, and 4.84 ± 0.51 μg/ml in the control group (P< 0.001). The serum haptoglobin level of infected cattle was found to be 2.08 ± 0.65 ng/ml, while that of the control group was determined as 3.87 ± 0.91 ng/ml (P>0.05). The highest concentrations of IL-6 were detected in serum of the cattle where microbial growth had been detected, followed by cattle infected with bacteria + Trichostrongylus sp. (P< 0.001). Consequently, SAA showed an important increase in the group infected with hydatid cysts, whereas haptoglobin level decreased. It was noticed that IL-6, like SAA, had a significant role in hydatid cyst infection. Therefore IL-6 and SAA appear to be major markers in the detection of infection of cattle with hydatid cysts.

Previous studies of dietary isotope discrimination have led to the general expectation that a consumer will exhibit enriched stable isotope levels relative to its diet. Parasite–host systems are specific consumer–diet pairs in which the consumer (parasite) feeds exclusively on one dietary source: host tissue. However, the small numbers of studies previously carried out on isotopic discrimination in parasite–host (ΔXP-HT) systems have yielded controversial results, showing some parasites to be isotopically depleted relative to their food source, while others are enriched or in equilibrium with their hosts. Although the mechanism for these deviations from expectations remains to be understood, possible influences of specific feeding niche or selection for only a few nutritional components by the parasite are discussed. ΔXP-HT for multiple isotopes (δ13C, δ15N, δ34S) were measured in the pike tapeworm Triaenophorus nodulosus and two of its life-cycle fish hosts, perch Perca fluviatilis and pike Esox lucius, within which T. nodulosus occupies different feeding locations. Variability in the value of ΔXP-HT calculated for the parasite and its different hosts indicates an influence of feeding location on isotopic discrimination. In perch liver ΔXP-HT was relatively more negative for all three stable isotopes. In pike gut ΔXP-HT was more positive for δ13C, as expected in conventional consumer–diet systems. For parasites feeding on pike gut, however, the δ15N and δ34S isotope values were comparable with those of the host. We discuss potential causes of these deviations from expectations, including the effect of specific parasite feeding niches, and conclude that ΔXP-HT should be critically evaluated for trophic interactions between parasite and host before general patterns are assumed.

The head region of 72 bullet tuna Auxis rochei from the western Mediterranean Sea (south-east Spain and the Strait of Gibraltar) was examined for parasites. Seven metazoan species were found in the fish from south-east Spain: three monogeneans, two trematodes and two copepods, whereas only three species were isolated in the fish from the Strait of Gibraltar. A comparison of the levels of infection of the parasites according to fish size in south-east Spain showed that the prevalence of Didymozoon auxis and the mean abundance of Allopseudaxine macrova were higher in the larger hosts (range of fork length = 38–44 cm) than in the smaller ones (33–37 cm). A comparison of the parasite infections according to geographical region showed that the mean abundances of Nematobothriinae gen. sp. and Caligus bonito were higher in fish from south-east Spain than in those from the Strait of Gibraltar. A comparison of the parasite fauna of A. rochei from the Mediterranean Sea with the published data on Auxis spp. from the Atlantic, Indian and Pacific Oceans revealed the closest similarity between the Mediterranean A. rochei and the Atlantic A. thazard.

An investigation was carried out on the distribution and biodiversity of steinernematid and heterorhabdtid entomopathogenic nematodes (EPN) in nine regions of Italy in the period 1990–2010. More than 2000 samples were collected from 580 localities and 133 of them yielded EPN specimens. A mapping of EPN distribution in Italy showed 133 indigenous EPN strains belonging to 12 species: 43 isolates of Heterorhabditis bacteriophora, 1 of H. downesi, 1 of H. megidis, 51 of Steinernema feltiae, 12 of S. affine, 4 of S. kraussei, 8 of S. apuliae, 5 of S. ichnusae, 3 of S. carpocapsae, 1 of S. vulcanicum, 3 of Steinernema ‘isolate S.sp.MY7’ of ‘S. intermedium group’ and 1 of S.arenarium. Steinernematids are more widespread than heterorhabditids and S. feltiae and H. bacteriophora are the most commonly encountered species. Sampling sites were grouped into 11 habitats: uncultivated land, orchard, field, sea coast, pinewood, broadleaf wood, grasslands, river and lake borders, caves, salt pan and moist zones; the soil texture of each site was defined and the preferences of habitat and soil texture of each species was assessed. Except for the two dominant species, S. feltiae and H. bacteriophora, EPN occurrence tends to be correlated with a specific vegetation habitat. Steinernema kraussei, H. downesi and H. megidis were collected only in Sicily and three of the species recently described – S. apuliae, S. ichnusae and S. vulcanicum – are known only from Italy and seem to be endemic.

Polycystic echinococcosis, caused by the larval stage (metacestode) of the small-sized tapeworm, Echinococcus vogeli, is an emerging parasitic zoonosis of great public health concern in the humid tropical rainforests of South and Central America. Because morphological and morphometric characteristics of the metacestode are not well known, hydatid cysts from the liver and the mesentery were examined from patients following surgical procedures. Whole mounts of protoscoleces with rostellar hooks were examined under light and confocal laser scanning microscopy. Measurements were made of both large and small hooks, including the total area, total length, total width, blade area, blade length, blade width, handle area, handle length and handle width. The results confirmed the 1:1 arrangement of hooks in the rostellar pad and indicated, for the first time, that the morphometry of large and small rostellar hooks varies depending upon the site of infection. Light and confocal microscopy images displayed clusters of calcareous corpuscles in the protoscoleces. In conclusion, morphological features of large and small rostellar hooks of E. vogeli are adapted to a varied environment within the vertebrate host and such morphological changes in calcareous corpuscles occur at different stages in the maturation of metacestodes.

With the aim of genotyping Echinococcus granulosus cysts found in Iranian dromedaries (Camelus dromedarius), 50 cysts of E. granulosus were collected from five geographical regions in Iran. Cysts were characterized using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the internal transcribed spacer 1 (ITS1) gene and sequencing fragments of the genes coding for mitochondrial cytochrome c oxidase subunit 1 (cox1). Morphological criteria using rostellar hook dimensions were also undertaken. The present results have shown that 27 out of 50 E. granulosus cysts (54%) were determined as the G1 strain, and the other (46%) were determined as the G6 strain. The molecular analysis of the ITS1 region of ribosomal DNA corresponded with the morphological findings. Because of its recognized infectivity in humans, the G1 genotype is a direct threat to human health and its presence in Iranian dromedaries is of urgent public health importance.

Anisakidosis is a human parasitic disease caused by infections with members of the Anisakidae family. Accidental infection after fish intake affects the gastrointestinal tract as a consequence of mechanical damage caused by migrating larvae. Infections can also trigger allergies, hives, severe asthma or anaphylaxis with angioedema. Although mouse models of intraperitoneal antigenic stimulation exist, enabling immunological studies, few models using gastric introduction of live larvae are available for the study of immunological and gastrointestinal damage in mice. This study was designed to characterize serum reactivity against Anisakis spp. and Contracaecum spp. in Balb/c mice following orogastric inoculation and to assess gastrointestinal damage. These anisakid species were classified at the Universidade Federal Fluminense (UFF) School of Veterinary Medicine and materials for live larval inoculation were developed at the UFF Immunobiology laboratory. Live larvae were inoculated following injection with a NaCl solution. Blood samples were collected and sera screened for immunoglobulin (Ig)E and IgG anti-larva responses to both nematodes, specific for somatic and excretory/secretory antigens, by enzyme-linked immunosorbent assay (ELISA). The means of the optical densities were analysed using analysis of variance (ANOVA) with Tukey's post-hoc test and the general linear model. This analysis identified the presence of anti-IgG seroreactivity to both somatic and excretory/secretory Anisakis antigens in inoculated animals compared with controls (P< 0.001), and no gastric or intestinal damage was observed. These experiments demonstrated that introduction of live Contracaecum spp. into the gastrointestinal tract did not elicit serum sensitization in animals.

Helminths use several strategies to evade and/or modify the host immune response, including suppression or inactivation of the host antigen-specific response. Several helminth immunomodulatory molecules have been identified. Our studies have focused on immunosuppression induced by the roundworm Ascaris suum and an A. suum-derived protein named protein 1 from A. suum (PAS-1). Here we assessed whether PAS-1 is an excretory/secretory (E/S) protein and whether it can suppress lipopolysaccharide-induced inflammation. Larvae from infective eggs were cultured in unsupplemented Dulbecco's modified Eagle medium (DMEM) for 2 weeks. PAS-1 was then measured in the culture supernatants and in adult A. suum body fluid at different time points by enzyme-linked immunosorbent assay (ELISA) with the monoclonal antibody MAIP-1. Secreted PAS-1 was detected in both larval culture supernatant and adult body fluid. It suppressed lipopolysaccharide (LPS)-induced leucocyte migration and pro-inflammatory cytokine production, and stimulated interleukin (IL)-10 secretion, indicating that larval and adult secreted PAS-1 suppresses inflammation in this model. Moreover, the anti-inflammatory activity of PAS-1 was abolished by treatment with MAIP-1, a PAS-1-specific monoclonal antibody, confirming the crucial role of PAS-1 in suppressing LPS-induced inflammation. These findings demonstrate that PAS-1 is an E/S protein with anti-inflammatory properties likely to be attributable to IL-10 production.

Dirofilaria immitis is endemic in Portugal. Several studies have reported the presence of canine heartworm disease, although no previous studies on feline infections have been published. The aim of this study was to determine the prevalence of D. immitis in cats and dogs from central and northern Portugal. Blood samples from 434 cats were tested for circulating anti-D. immitis and anti-Wolbachia antibodies. Furthermore, 386 dogs were tested for circulating D. immitis antigens. Overall feline seroprevalence was 15%, while canine prevalence was 2.1%. The highest feline seroprevalences of 18.7% and 17.6% were found in Aveiro and Viseu, respectively, while the highest canine prevalences of 8.8% and 6.8% were found in Coimbra and Aveiro, respectively. Cats and dogs showing respiratory signs presented higher prevalences of 24.4% and 17%, respectively, while 50% of cats with gastrointestinal signs were seropositive. The present study confirms the seropositivity of D. immitis in the feline population in central and northern Portugal, and suggests the importance of including heartworm disease in the list of differential diagnoses of cats and dogs showing clinical signs compatible with the disease.