Experimental infections of Egyptian Radix natalensis with a French isolate of Fasciola hepatica (each snail was subjected twice to a bimiracidial exposure) were carried out to determine how many sporocysts grew in these snails and to study the developmental patterns of redial generations. Single-sporocyst infections were found in 69.3% (34/49) of infected snails, with equivalent numbers of normal and abnormal patterns. Snails with two- and three-sporocyst infections were 24.4% and 6.1%, respectively. In single- and two-sporocyst infections at days 42 and 56 post-exposure, the total redial burden was significantly higher in snails with a normal redial development. In two- and three-sporocyst infections, the overall maturity of rediae was delayed at days 42 and 56. The high frequency of abnormal patterns in R. natalensis (53.1% of all infected snails showed degeneration of a first mother redia) might be due to incomplete adaptation between the snail population and the parasite. The delayed redial maturity in two- and three-sporocyst infections can mainly be explained by the volume of the snail body, which would be insufficient to allow the simultaneous differentiation of most rediae over time.

The efficacy of eprinomectin on Dictyocaulus filaria and Cystocaulus ocreatus in naturally infected sheep was evaluated in the present study. In total, 30 infected sheep were randomly divided into two groups: treated (n = 15) and untreated (n = 15). A single pour-on dose of eprinomectin (0.5 mg/kg) was administered to the treated group. No medication was used in the untreated group. Faecal larval counts were performed on pre-treatment (day 0) and post-treatment (days 7, 14, 21 and 42) days. Eprinomectin was found to be 100% effective against D. filaria on day 7 post-treatment when compared with the untreated group and it maintained this effect on days 14, 21 and 42. However, the decrease in faecal larval count of C. ocreatus was found to be 86, 86 and 91%, on days 14, 21 and 42, respectively.

Following our previous field surveys for strongyloidiasis in western Uganda, 120 mothers and 232 children from four villages in eastern Uganda were examined, with two subsequent investigative follow-ups. As before, a variety of diagnostic methods were used: Baermann concentration, Koga agar plate and strongyloidid enzyme-linked immunosorbent assay (ELISA), as well as Kato–Katz faecal smears for detection of eggs of other helminths. At baseline, the general prevalence of Strongyloides stercoralis was moderate: 5.4% as estimated by Baermann and Koga agar methods combined. A much higher estimate was found by ELISA (42.3%) which, in this eastern setting, appeared to be confounded by putative cross-reaction(s) with other nematode infections. Preventive chemotherapy using praziquantel and albendazole was offered to all participants at baseline. After 21 days the first follow-up was conducted and ‘cure rates’ were calculated for all parasites encountered. Eleven months later, the second follow-up assessed longer-term trends. Initial treatments had little, if any, effect on S. stercoralis, and did not alter local prevalence, unlike hookworm infections and intestinal schistosomiasis. We propose that geographical patterns of strongyloidiasis are likely not perturbed by ongoing praziquantel/albendazole campaigns. Antibody titres increased after the first follow-up then regressed towards baseline levels upon second inspection. To better define endemic areas for S. stercoralis, careful interpretation of the ELISA is warranted, especially where diagnosis is likely being confounded by polyparasitism and/or other treatment regimens; new molecular screening tools are clearly needed.

This study used Balb/c mice to examine the longevity of Zygocotyle lunata in a murine host. Of 11 mice, each exposed to 20 Z. lunata cysts, six were infected with a total of 12 worms from 11 to 24 weeks postinfection (PI). Live worms recovered at 24 weeks PI had a mean body area of about 25 mm2. These worms produced viable eggs with well-developed miracidia following embryonation in artificial spring water for 2 weeks at 28°C. The Balb/c mouse is a useful model to study longevity of this paramphistomid trematode for at least 6 months PI. An additional aspect of this article is a review of the pertinent literature published from 1937 to 2007 on ageing and longevity of digeneans.

This paper provides an estimation of the point prevalence of fascioliasis and its economic impact in terms of increased milk yield after chemotherapy of a bovine population from the district of Toba Tek Singh, Punjab, Pakistan. A total of 2400 cattle and buffaloes were examined quantitatively using the McMaster egg-counting technique. Infected cattle and buffaloes (50 of each) were randomly selected and each divided into two groups of 25 animals. Groups A (buffaloes) and C (cattle) were treated with oxyclozanide (orally, 16.6 mg kg− 1 body weight). Groups B and D served as negative controls for buffaloes and cattle, respectively. Pre- and post-treatment milk yield was recorded to determine if there were any changes in milk yield after treatment. Of 2400 faecal samples analysed, 654 (27.25%) were positive for Fasciola spp. with a mean number of eggs per gram (EPG) of 503.2. The point prevalence and worm burden of fascioliasis was significantly higher (OR = 2.13; P < 0.05) in buffaloes (34.58%; 415/1200; mean EPG maximum likelihood = 521.4) as compared to that of cattle (19.92%; 239/1200; mean EPG maximum likelihood = 415.8). Among the parasite species, F. gigantica (19.88%; 477/2400) was predominant (OR = 3.12; P < 0.05) as compared to F. hepatica (7.38%; 177/2400). An average daily increase of 0.67 and 0.87 litres of milk, with 0.41% and 0.37% more fat per animal, was observed in oxyclozanide-treated buffaloes and cattle, respectively. The economic value of reduced production of infected animals was estimated as US$0.33 and 0.32 per animal per day for cattle and buffaloes, respectively.

A total of 299 fish belonging to ten teleost species were studied in Iranian waters at the north-eastern coast of the Persian Gulf for larval trypanorhynch cestode infection. The following trypanorhynch species were identified: Callitetrarhynchus gracilis Pintner, 1931, Pseudogilquinia thomasi (Palm, 2000), Pterobothrium lesteri Campbell and Beveridge, 1996 and Pseudolacistorhynchus shipleyi (Southwell, 1929). The most abundant parasite was C. gracilis which was isolated from seven teleost species. The highest prevalence (62.9%) and dominance (0.98) were demonstrated for P. thomasi with a maximum intensity of 22 in Indian halibut Psettodes erumei. Collections of P. lesteri and P. shipleyi from the Persian Gulf represent new locality records, thus extending the known range of distribution for both species. Four new host records are established. The recorded combination of trypanorhynch species and the established host range correspond to other regions, such as off the Brazilian coast. In terms of species distribution, the north-western part of the Indian Ocean, together with the Gulf of Bengal and the Indonesian archipelago, share the same species, resulting from connected water bodies. All trypanorhynch species were isolated from the body cavity, except for P. thomasi which was recorded from the musculature of P. erumei. Relatively high intensities of infection in P. erumei may be of public health concern in the region, necessitating the consumption of well-cooked fish products.

The tapeworm Ligulaintestinalis commonly infests roach (Rutilusrutilus) and is responsible for the inhibition of gonad development. In order to better understand the effect of the plerocercoid on fish physiology, and to discriminate parasitization effects from those of endocrine-disrupting compounds (EDC), Cyp19b and Cyp19a aromatase expression was investigated by real-time quantitative polymerase chain reaction (PCR) in brain and gonads of ligulosed roach, caught from a reference site. Data were compared to reproductive and endocrine endpoints previously reported in a larger cohort study (including the sampled population of the present one), such as gonadosomatic index, Fulton index, gonadal histology, plasma sex steroid levels and brain aromatase activity. A decrease in Cyp19b expression in the brain of infected fish was demonstrated, in agreement with the reduction of aromatase activity previously described. In contrast, Cyp19a expression in the gonads appeared to be enhanced in ligulosed fish, in accordance with the presence of immature but differentiated sexual tissues. Together these results show that: (1) L. intestinalis infestation results in an alteration of aromatase expression which, in particular, may have profound effects on the fish brain; and (2) L. intestinalis infection must be considered as a major confounding factor in ecotoxicological studies using aromatase expression as an EDC biomarker. Moreover, the concordance between activity and expression – investigated for the first time in the same population – gives a functional relevance to the transcript aromatase dosage in the brain. Finally, quantitative PCR was confirmed as a sensitive approach, enabling aromatase status to be defined in the poorly developed gonads of ligulosed individuals.

A 6-year retrospective study based on abattoir records was carried out to determine the prevalence of hydatidosis in dromedaries in Khorasan province in north–eastern Iran. Between 20 March 2004 and 19 March 2010, 25,255 dromedaries were slaughtered in the study area and the livers of 2791 (11.1%) and the lungs of 3289 dromedaries (13.2%) were discarded due to hydatidosis. The annual prevalence of liver condemnations due to hydatidosis decreased from 24.1% in 2004–2005 to 13.3% in 2009, and finally to 6.8% in 2010. The corresponding features for lung condemnation due to hydatidosis were relatively higher than liver, declining from 28.7% in 2004–2005 to 14.9% in 2009, and finally to 7.1% in 2010. Liver and lung condemnations due to hydatidosis were significantly higher in the spring. This could be attributed to various factors such as sources of slaughtered animals, changes in management practice and ecological factors. The present survey provides baseline data for the future monitoring of this potentially important parasitic disease in the region.

Bird schistosomes can cause a disease called cercarial dermatitis, or swimmer's itch, in humans. The disease occurs when people have direct contact with fresh water or sea water containing the free-swimming cercariae of the flukes. The symptoms are well known, and include intense itching, maculae, papulae, urticariae and, in some cases, local oedema with enlarged lymph nodes and fever. In this study, we present the geographical distribution of freshwater cercarial dermatitis in Norway. The study is based on random reports obtained from both individuals and physicians treating patients with itching skin rash after freshwater bathing. The first case of cercarial dermatitis in Norway was reported in 1980 and was traced to a lake near Trondheim in the central part of Norway. In the following years, an increasing number of cases were reported, especially in southern Norway. However, case reports are distributed almost all over the country, even from lakes in northern Norway. As far as we know, these are the northernmost case reports in Europe. So far, only one fluke species (Trichobilharzia franki) from a single infected snail (Radixauricularia) has been identified in Norway. However, unidentified schistosomatid ocellate cercariae have been found on several occasions in snails collected from six lakes where swimmer's itch is frequently reported. Future studies should be performed to identify the fluke species, as well as the most important snail and bird hosts, in Norwegian lakes.