A study was carried out on the gastrointestinal helminth communities of blackspot seabream, Pagellus bogaraveo, from the Portuguese mainland and island waters. Fifteen helminth parasite species were detected, including the following new records in this host: the digeneans Accacladocoelium petasiporum, Brachyenteron helicoleni,Glomericirrus macrouri, Lecithocladium excisum, Lepocreadium album and Pachycreadium carnosum; the nematode Camallanus sp. and the acanthocephalan Rhadinorhynchus pristis. Infection levels were generally low. Samples from mainland waters had a significantly higher prevalence of digeneans than those from the islands, probably due to the greater availability of invertebrate intermediate hosts on the continental slope. The helminth community of P. bogaraveo from Azores was diverse but mostly composed of species that infected no more than a single host, whereas in Madeira the helminth community was very depauperate. Most helminth species exhibited niche preferences within the gastrointestinal tract of the host. Higher functional richness and evenness were obtained in helminth communities of P. bogaraveo from mainland waters, indicating a balanced use of available resources, which is suggestive of more stable gastrointestinal helminth communities in these waters.

A new entomopathogenic nematode in the genus Heterorhabditis is described from South Africa, from two singular isolates found 1000 km from each other, from beneath a fig tree and in a citrus orchard, respectively. Morphological and molecular studies indicate both isolates to be the same and a new undescribed Heterorhabditis species. Comparison of sequences of the internal transcribed spacer (ITS) rDNA and the D2D3 region of the 28S rDNA gene with available sequences of other described species within the genus, indicate the two isolates as a new species. Phylogenetic analysis of the sequence data concerned placed the new species, H. noenieputensis n. sp., closest to H. indica and H. gerrardi in the indica-group. The new species, H. noenieputensis n. sp., is distinguished from other species in the genus by a combination of several morphological traits of the males and the infective juveniles (IJs). The new species differs from all other species previously described, as regards the body length of the IJs, except for H. indica and H. taysearae, in which the IJ is smaller. The IJ also differs from that of H. indica in the length of the oesophagus, the body diameter, the length of the tail and the E%. In addition, males of H. noenieputensis n. sp. differ from their closest relative, H. indica, in the position of the excretory pore, SW% and D%; and from H. gerrardi in the length of the oesophagus and SW%. The seventh pair of genital papillae of H. noenieputensis n. sp. are normally developed, while for H. indica they are often branched or swollen at the base, while 8 and 9 are usually absent in both species.

In this cross-sectional study, the associations between helminth infections and ABO blood group, anaemia and undernutrition were investigated in 480 febrile outpatients who visited Dore Bafeno Health Centre, southern Ethiopia, in December 2010. Stool specimens were processed using the Kato–Katz method and examined for intestinal helminth infections. Haemoglobin level was measured using a HemoCue machine and blood group was determined using an antisera haemagglutination test. Nutritional status of the study participants was assessed using height and weight measurements. Among the study participants, 50.2% were infected with intestinal helminths. Ascaris lumbricoides (32.7%), Trichuris trichiura (12.7%), Schistosoma mansoni (11.9%) and hookworm (11.0%) were the most frequently diagnosed helminths. The odds of infection and mean eggs per gram of different intestinal helminth species were comparable between the various blood groups. Among individuals who were infected with intestinal helminth(s), the mean haemoglobin level was significantly lower in individuals harbouring three or more helminth species and blood type AB compared to cases with double or single helminth infection and blood type O, respectively. The odds of being underweight was significantly higher in A. lumbricoides and T. trichiura infected individuals of age ≤ 5 and ≥ 20 years, respectively, when compared to individuals of the matching age group without intestinal helminths. In conclusion, infection with multiple intestinal helminths was associated with lower haemoglobin level, which was more severe in individuals with blood type AB. Future studies should focus on mechanisms by which blood group AB exacerbates the helminth-related reduction in mean haemoglobin level.

Levels of calcium in the haemolymph and reserves in the shell of Biomphalaria glabrata experimentally infected by Angiostrongylus cantonensis were determined for the first time. At the same time, histochemical analyses of the digestive gland of infected and uninfected snails were performed to better understand the possible changes in metabolism of calcium in these organisms. After 1, 2 and 3 weeks of infection, the snails were dissected for collection of haemolymph and separation of tissues. The highest calcium concentrations in the haemolymph were found 2 weeks after infection, with a 39.61% increase in relation to the respective control group. However, there was a significant reduction in the concentration of this ion in the haemolymph of infected snails after 1 week of infection in relation to the uninfected specimens. In parallel, intense hypocalcification was shown in the shell of infected snails 1 and 2 weeks after infection, differing significantly in relation to the respective control groups. Morphological changes in the digestive gland of infected snails were also observed, confirming the role of this ion as an important element in the parasite encapsulation process.

A new species, Paradiplozoon ichthyoxanthon (Monogenea: Diplozoidae) is described from the gills of Labeobarbus aeneus (Cyprinidae) in the Vaal Dam and Vaal River Barrage in the Vaal River, South Africa. This species is the first in this genus from southern Africa; Paradiplozoon aegtyptense and Paradiplozoon ghanense have been described from northern Africa. The new species differs from all other Paradiplozoon species on the basis of the combination of morphological characteristics, namely disk-like haptor, eggs without filaments, clamp and central hook morphology and size of specimens. The species description is accompanied by a description of the reproductive organs. The internal transcribed spacer of the ribosomal gene (ITS2) was studied and the South African individuals formed a distinct clade, supporting the establishment of a new species.

The epidemiology of toxocariasis in humans in Mexico has been poorly explored. There is a lack of information about toxocariasis in Tepehuanos, an indigenous ethnic group in Durango State in northern Mexico. Therefore, the presence of anti-Toxocara immunoglobulin (Ig) G antibodies was determined in 126 rural Tepehuanos using an enzyme-linked immunoassay. Socio-demographic, clinical and behavioural data of the participants were also obtained. Of the 126 Tepehuanos assessed (mean age 32.46 ± 17.36 years), 33 (26.2%) had anti-Toxocara IgG antibodies. Multivariate analysis showed that Toxocara seropositivity was associated with unemployment (students and housewives) (odds ratio (OR) = 3.1; 95% confidence interval (CI) 1.25–7.47). Other socio-demographic and behavioural characteristics, including age, educational level, contact with animals or soil, consumption of unwashed raw fruits and vegetables or untreated water, were not associated with Toxocara seropositivity. Clinical data were similar in seropositive and seronegative Tepehuanos. These results indicate that Toxocara exposure is common among Tepehuanos but Toxocara does not appear to impact on the health of the population. This is the first report of toxocaral infection in Tepehuanos, and of an association of toxocariasis in adults with unemployment. Further research is needed to elucidate the routes of transmission of Toxocara in Tepehuanos, including the role of hygiene practices, canine and feline contacts, paratenic hosts and soil contamination with infective Toxocara eggs.

Microphallid trematodes are common parasites in marine snails and crustacean hosts at Kuwait Bay. The larval stages of two microphallids, Maritrema eroliae and Probolocoryphe uca, are difficult to differentiate morphologically. In this study, two PCR-based techniques were established for quick and accurate discrimination between the larval stages of the two microphallid species, employing restriction fragment length polymorphism (PCR-RFLP) and species-specific primers. Both techniques utilized nucleotide differences in the second internal transcribed region (ITS2) of the ribosomal DNA (rDNA) in the two species. For the PCR-RFLP technique, restriction enzyme AvaII was selected and it generated different restriction profiles among the two microphallids. In addition, species-specific primers were prepared for each microphallid species that amplified distinctive fragments. Both techniques showed that the larval stages of the two microphallid species can be identified accurately. However, direct PCR amplification using species-specific primers was more advantageous than the PCR-RFLP technique since it allowed rapid and specific discrimination between the two species. This technique provides a useful tool that can be used in future studies for the study of the distribution of microphallid species and their definitive hosts at different localities of Kuwait Bay.

Fish-borne zoonotic trematodes (FZTs) can cause major human health problems. The aim of this study was to quantify the transmission of parapleurolophocercous cercariae to common carp (Cyprinus carpio) and to study the effect of the density of cercariae and the density of fish on transmission with respect to the volume of water and surface area of the bottom. Fish were kept individually either as controls (n= 91) or were exposed to 250 cercariae in tubes with a volume of 25, 50, 100, 250 or 500 ml water (n= 190) with a surface area of 4, 12, 21, 30 or 49 cm2 (n= 195). The dose to which the fish were exposed was kept constant. Infection occurred in 94–100% of fish, with a mean of 15–18 metacercariae per fish and the proportion of FZTs established at 0.06–0.07 metacercariae per cercariae per fish. Neither the prevalence of infection with FZTs nor the number of metacercariae per fish nor the proportion of FZTs established were significantly associated with differences in the density of cercariae or the density of fish per ml water or per cm2 surface area. Thus, it was concluded that the transmission of cercariae to fish is independent of density.

Coproantigen test kits for Echinococcus spp. worms in dogs, designed for commercial use, were obtained from three different Chinese producers, and were compared with a laboratory kit using reagents from New Zealand. None of the three producers would provide details of their test validation. From a known set of dog faeces obtained at necropsy from infected and uninfected dogs, and from faeces collected from dogs necropsied in the field, results differed between the kits. For field material, the Tiankang kit showed the best specificity but lacked sensitivity. The Combined kit showed best sensitivity but lacked specificity. Results for the Haitai kit were intermediate. With samples from experimentally infected dogs, both the Haitai and Combined kits lacked sensitivity. Kits will need to be validated by the user before they can be relied on to predict progress in Echinococcus spp. control in China or in other countries.

Numerous eggs of capillariid nematodes have been found in coprolites from a wide range of hosts and in raptor pellets in archaeological samples from Patagonia. The structure and sculpture of the eggshell of these nematodes and their biometry are commonly used for identification. The aim of this study was to determine whether eggs of the genus Calodium with similar morphology, found in different archaeological samples from Patagonia, belong to the same species. For this purpose, capillariid eggs (N= 843) with thick walls and radial striations were studied by permutational multivariate analysis of variance (PERMANOVA). Eggs exhibiting similar shape and structure also showed similar biometry, regardless of the zoological origin of coprolites (P= 0.84), host diet (P= 0.19), character of the archaeological sites (P= 0.67) and chronology (P= 0.66). Thus, they were attributed to the same species. We suggest that an unidentified zoonotic species of the genus Calodium occurred in the digestive tract of a wide range of hosts in Patagonia during the Holocene and that both human and animal populations were exposed to this parasite during the Holocene in the study area.

A survey of intestinal parasites in dogs was carried out in a rural region around Cantanhede, in northern Portugal, where 301 dog faecal samples were collected from small-ruminant farms. Saturated salt flotation and formol–ether sedimentation techniques were used. An enquiry was conducted in 234 farms and a risk factor evaluation for zoonotic helminths was determined among the 195 farmers who owned dogs. The overall parasite prevalence in faecal samples of dogs was 58.8%, with specific prevalences for Ancylostomidae being 40.9% followed by species of Trichuris (29.9%), Toxocara (8%), Isospora (4%), Capillaria (0.7%) and Spirometra (0.3%). Taeniidae eggs were present in five samples (1.7%) which were analysed with the polymerase chain reaction (PCR) technique and revealed to be from Taenia sp., and not Echinococcusgranulosus. This rural region has a traditional small-farm system, in which farm products are mainly for in-house consumption and home slaughtering is a current practice (57%). Analysis showed home slaughtering to be a statistically significant risk factor for the presence of Ancylostomidae (P= 0.007) and Toxocara sp. (P= 0.049). Owning cattle was found to be a significant risk factor for Taenia sp. (P= 0.031).

Inflammatory bowel disease (IBD) is a chronic relapsing inflammation afflicting any part of the bowel wall as a result of a deregulated and inappropriate immune response. In recent years, experimental and clinical evidence has demonstrated that infection with parasitic worms could protect hosts from IBD. The aims of this study were to determine if the underlying mechanism of the host immune regulation inherent to Trichinella spiralis infection involves Foxp3-expressing regulatory T cells, and to gain insight about time-related interactions between intestinal nematode infection and induced colitis using an experimental model for ulcerative colitis. Mice were experimentally subjected to acetic acid-induced colitis, which was either preceded or followed by T. spiralis infection. Assessment of colitis was done by histopathological examination of the colon and determination of pentraxin 3 levels. Immunohistochemistry was done for demonstration of Foxp3-expressing regulatory T cells in colonic tissues. It was evident that T. spiralis infection ameliorated the severe inflammation induced by acetic acid, evidenced by amelioration of histopathological changes and diminution of pentraxin 3 levels. The amelioration was more pronounced when T. spiralis infection preceded the induction of colitis. Regarding the immunohistochemical staining of regulatory T cells, T. spiralis infection induced recruitment of Foxp3-expressing regulatory T cells to areas of inflammation. In conclusion, T. spiralis regulatory mechanism can improve inflammation of the colon through the ‘inflammatory–regulatory’ axis. Finally, it would be of great importance to apply these results to the development of new therapeutic approaches for the treatment of ulcerative colitis.

Nematodes of the family Thelastomatidae are parasitic in the alimentary tract of many arthropods, including Periplaneta americana L. In Meerut, Uttar Pradesh, India, two nematode species, namely Hammerschmidtiella indicus and Thelastoma icemi, belonging to this family have been reported. In the present study, the molecular phylogeny of these two nematode species was derived using small subunit (18S) sequence and secondary-structure analyses. The small subunit sequence analyses were carried out to explore the validation and systematics of these species. Phylogenetic analyses were performed for primary sequence data as well as using neighbour-joining and maximum-parsimony approaches. In contrast, the inferred secondary structures for the two species, using free-energy modelling, showed structural identities. As well as this, motif sequences were also found to be a promising tool for nematode species identification. The study provides molecular characterization based on primary sequence data of the 18S ribosomal DNA region of the nematodes along with secondary-structure data and motif sequences for inferences at higher taxonomic levels.

The life-cycle stages of Pleurogenoides malampuzhensis sp. nov. infecting the Indian bullfrog Hoplobatrachus tigerinus (Daudin) and the skipper frog Euphlyctiscyanophlyctis (Schneider) occurring in irrigation canals and paddy fields in Malampuzha, which forms part of the district of Palakkad, Kerala, are described. The species is described, its systematic position discussed and compared with the related species, P. gastroporus (Luhe, 1901) and P. orientalis (Srivastava, 1934). The life-cycle stages, from cercaria to egg-producing adult, were successfully established in the laboratory. Virgulate xiphidiocercariae emerged from the snail Digoniostoma pulchella (Benson). Metacercariae are found in muscle tissues of dragonfly nymphs and become infective to the frogs within 22 days. The pre-patent period is 20 days. Growth and development of both metacercariae and adults are described.

In the present investigation a sample of 490 cod (Gadus morhua) was examined from three regions in the southern Baltic Sea (the Polish Exclusive Economic Zone, EEZ). Three species of anisakid nematodes with zoonotic potential, namely species of Contracaecum, Anisakis and Pseudoterranova, were found in the liver of cod, with Contracaecum being the most dominant species. The prevalence of infection was highest in the Western Baltic (22.5%) compared to the Central Baltic (10.4%) and the Gulf of Gdansk (3.4%). Generalized linear models (GLMs) were applied to analyse the prevalence of infection with Anisakis sp. and Contracaecum sp. relative to biological and spatial parameters. The effect of the sampling region, age and body length of the fish were significant in both GLMs. The effect of region was higher in the Western Baltic than in other regions. The prevalence of infection was correlated with the length of the fish and was higher in adult compared with sub-adult fish. These results suggest that the prevalence of infection with anisakid nematodes (especially Contracaecum sp.) in cod sampled in Polish waters of the Baltic Sea has significantly increased compared with previous studies undertaken over the past few decades.

The trematode Alaria alata, an intestinal parasite of different carnivore species is widely distributed throughout Europe. The mesocercarial stages of Alaria spp. may infect almost all vertebrate species, including humans, and, in particular, omnivorous scavengers such as wild boars serve as paratenic hosts for the parasite. The introduction of the A. alata mesocercariae migration technique (AMT) opened the way to a reliable detection of Alaria spp. mesocercariae in different body tissues of their paratenic hosts. For the first time, it was possible to detect vital A. alata mesocercariae from two Bulgarian wild boars by means of this new method. In addition, polymerase chain reaction (PCR) examination of the respective parasitic DNA allowed the unequivocal species identification of the parasites as A. alata. Isolation and molecular biological identification of the parasite's developmental stages make significant contributions to completion of data on both the distribution of Alaria spp. in stocks of European game and the relationship between different Eurasian Alaria spp. isolates.

Cases of canine onchocerciasis caused by Onchocerca lupi are increasingly reported from Europe and the western United States of America. The zoonotic role of this parasite had already been suspected in Europe as the clinical signs and histopathology seen in two ocular cases from Albania and the Crimean region were very similar to those of canine ocular onchocerciasis. In the most recent reports of human onchocerciasis, O. lupi has been morphologically and molecularly identified as the causative agent of ocular infestation in two patients from Turkey, and one patient from Tunisia. Here, we report an additional case of nodular lesions involving two, and possibly more, immature worms in a patient from Iran. The parasite was found to belong to the genus Onchocerca based on morphological features and the species was confirmed as O. lupi from a partial sequence analysis of 12S ribosomal DNA.