Kazakhstan is highly endemic for echinococcosis. Both Echinococcus granulosus and E. multilocularis are widely distributed in the country. Official records of human cystic echinococcosis over the past 5–10 years suggest a stable incidence of approximately 800–1000 cases per year, which is 5 cases per 100,000 per year. This followed a rapid increase in the incidence following the dissolution of the Soviet Union. Between 2007 and 2013, 5949 cases were reported in the national surveillance data. The prevalence in sheep, based on slaughterhouse studies, suggests that between 30 and 50% of sheep are infected with hydatid cysts, while cattle have a prevalence of approximately 7%. Rural dogs have a high prevalence of infection of between 5 and 10%, with shepherd dogs having prevalences of over 20%. G1 and G6/7 strains of E. granulosus have been isolated from dogs in Kazakhstan. Wolves are also infected, with one prevalence estimate of approximately 20%. The incidence of human alveolar echinococcosis is less clear, although estimates from Kazakhstani expatriates living in Germany and the hospital records of a single referral centre in Almaty suggest 34 or 130 cases per year (or an annual incidence of 0.20 or 0.76 cases per 100,000), respectively, could be occurring in Kazakhstan. Studies suggest that in some rural dog populations the prevalence may be about 5%. The parasite is widely distributed in foxes and small mammals through much of Kazakhstan.

Canine hookworm infections are endemic worldwide, with zoonotic transmission representing a potentially significant public health concern. This study aimed to investigate hookworm infection and identify the prevalent species from stray and shelter dogs in Guangzhou city, southern China by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) based on internal transcribed spacer (ITS) sequences. From March 2011 to July 2012, fresh faecal samples from a total of 254 dogs were obtained from five locations, namely Conghua, Baiyun, Liwan, Haizhu and Panyu, in Guangzhou. These samples were screened for the presence of hookworm eggs using light microscopy, with an overall prevalence of 29.53% being recorded. The highest prevalence of 45.28% was found in suburban dogs from Conghua compared with lower values recorded in urban dogs in Haizhu (21.43%), Baiyun (18.97%), Panyu (18.18%) and Liwan (15%). The prevalence in stray dogs was significantly higher than that in shelter dogs. PCR-RFLP analysis showed that 57.33% were detected as single hookworm infections with Ancyclostoma caninum, and 22.67% as A. ceylanicum, while 20% were mixed infections. This suggests that high prevalences of both hookworm species in stray and shelter dogs in China pose a potential risk of transmission from pet dogs to humans.

Growth rate and activity of 10 nematode trapping fungi, (Hyphomycetes)—Arthrobotrys oligospora, Dactylaria brochopaga, D. gamsospora, D. polycephala, D. thaumasia, D. vermicola, Monacrosporium (Dactylella) bembicodes, M. {D.) cionopaga, M. {D.) ellipsospora, Trichothecium cystosporium—against the infective larvae of Ostertagia ostertagi and Trichostrongylus axei were studied. Species forming adhesive networks grew faster than the others. Species producing adhesive knobs, adhesive branches and constricting rings were, in general, slow growers.

An inverse relationship has been demonstrated between egg counts and antibody titres. This relationship is also evident on a seasonal basis in the “spring rise”.

The “spring rise” is preceded by a decrease in the immune status of the sheep and is terminated by a self cure mechanism which establishes a period of protection.

The significance of these findings is discussed with regard to the onset and development of the “spring rise”.

A survey of 612 black rats, Rattus rattus (282 males and 330 females), for infections with helminth parasites was carried out in Abeokuta, in southwest Nigeria. Three hundred and ninety six (64.7%) were infected with one or more of seven species of helminths comprising three cestodes (Hymenolepis diminuta, Taenia taeniaeformis (cyst) and Raillietina sp.) three nematodes (Mastophorus muris, Trichuris muris and Syphacia sp.) and one acanthocephalan (Moniliformis moniliformis). Although the prevalence of infection in males (76.6%) was more than in females (54.5%) (P< 0.01), there was no difference in the mean intensity of infection, MI, (males = 11.6 ± 0.94, females = 11.1 ± 1.56). Among the different weight classes, rats of 100–130g were more infected (89.3%) and had the highest mean intensity (MI = 21.6) than those that weighed <100g (47.1%, MI = 6.4) and >130g (73.9%, MI = 9.3). Moniliformis moniliformis was the most common species encountered (39.2%) and had the highest mean intensity in both sexes ( = 7.4 ± 0.74). Considering the rat-man proximity, this finding has considerable public health implications.

A pellet of sheep faeces containing eggs of Haemonchus contortus forms an adequate environment for the development of those eggs to third stage infective larvae, provided that it is kept moist. Observation shows a concentration of developing larvae on the external mucous coat of the pellet. These data suggest that optimum conditions for development would occur when pellets are separated one from another and standing on a water repellent surface, thus presenting the maximum free surface area and minimum opportunity for aggregation and hence of over crowding. The best method of recovering the infective larvae would be one that obtained larvae free from contamination without requiring them to expend energy in separating themselves from the contamination.

A wild population of the lymnaeid snail Pseudosuccinea columella infected by larval stages of Fasciola hepatica was discovered in the Pinar del Río Province, Cuba. One of 100 snails was infected in a rice culture field. This is the first time this species has been found acting as intermediate host of F. hepatica under natural conditions, not only for Cuba but also for the Caribbean area.

The in vitro effects of extracts of four tropical plants (Zanthoxylum zanthoxyloides, Newbouldia laevis, Morinda lucida and Carica papaya) on the egg, infective larvae and adult worms of Trichostrongylus colubriformis were screened for potential anthelmintic properties. Significant effects were observed with the four plants on T. colubriformis but they differed depending on the stage of the parasite. Extracts of each plant induced a dose-dependent inhibition of egg hatching. Using a larval inhibition migration test, the effects on the infective larvae were also detected with the four plant extracts. In contrast, for adult worms, the effects were statistically significant only for N. laevis and C. papaya. No significant activity was shown for M. lucida and Z. zanthoxyloides. These in vitro results suggest the presence of some anthelmintic properties associated with these four plants, which are traditionally used by small farmers in western Africa. These effects need to be studied under in vivo conditions.

Various strains of Atlantic salmon exhibit different levels of susceptibility to infections with the ectoparasitic monogenean Gyrodactylus salaris. The basic mechanisms involved in this differential ability to respond to this monogenean were elucidated using controlled and duplicated challenge experiments. Highly susceptible East Atlantic salmon allowed parasite populations to reach up to 3000 parasites per host within 6 weeks, whereas less susceptible Baltic salmon never reached larger parasite burdens than 122 parasites per host during the same period. The present study, comprising immunohistochemistry and gene expression analyses, showed that highly susceptible salmon erected a response mainly associated with an increased expression of interleukin-1β (IL-1β), interferon-γ (IFN-γ), IL-10 and infiltration of CD3-positive cells in the epidermis of infected fins. Less susceptible salmon showed no initial response in fins but 3–6 weeks post-infection a number of other genes (encoding the immune-regulating cytokine IL-10, cell marker MHC II and the pathogen-binding protein serum amyloid A) were found to be up-regulated. No proliferation of epithelial cells was seen in the skin of less susceptible salmon, and IL-10 may play a role in this regard. It can be hypothesized that resistant salmon regulate the parasite population by restricting nutrients (sloughed epithelial cells and associated material) and thereby starve the parasites. In association with this ‘scorched-earth strategy’, the production of pathogen-binding effector molecules such as serum amyloid A (SAA) (or others still not detected) may contribute to the resistance status of the fish during the later infection phases.

1. The rate of development of the larvae of M. capillaris is slowed down as the temperature is lowered; at 25°C. the infective stage is reached after 8 days; at 5°C. after 98 days.

2. The differences between “pre-infective” and “infective” larvae, as described by Gerichter (1948), have been confirmed.

3. Larvae at the “infective” stage can withstand artificial digestion, but “pre-infective” larvae are unable to do so.

4. The infective larvae can survive for long periods within the foot of the intermediate host.

5. Pre-infective larvae can survive for seven days after the death of the intermediate host; infective larvae can live for sixteen days.

6. Naturally-infected slugs were found throughout the greater part of the year. 13.5 per cent of the slugs collected were infected but in most instances only a few larvae were present in any one slug.

The use of an indirect immunofluorescence technique demonstrated that serum from reindeer, Rangifer tarandus tarandus, infected with Elaphostrongylus rangiferi (Nematoda, Metastrongyloidea) contained antibodies directed against antigen(s) on the cuticle of the parasites first-stage larvae (LI). Output of LI from the male reindeer was low in the period June to August, but increased to a higher level during the rutting season (September to October). The titre of specific antibody showed an inverse pattern. In the female reindeer, larval output remained high throughout the sampling period from January to July. During this period antibody titre was low. A relationship between stress (rutting season or calving period), immunity and larval output is suggested.

Contamination of soil with feline and canine ascarid eggs in eight playgrounds in Kırıkkale, Turkey was investigated monthly from February 2003 to January 2004. Dog faeces were also collected and all samples were examined using the zinc sulphate centrifugal flotation method. Eggs of Toxocara were observed in 5 of 8 (62.5%) of playgrounds examined and in 15.6% of 480 soil samples. The number of eggs varied from 1 to 11. Eggs were observed in soil samples collected in February, March to June, August and November, with embryonated eggs appearing in June and August. Eggs of Toxascaris leonina and Taenia spp. and oocysts of Isospora spp. were also found in 1.5%, 1.0% and 0.2% of soil samples, respectively. Of 26 samples of dog faeces collected, 7.7% were contaminated with Toxocara spp. and 11.5% with Taenia spp. The presence of Toxocara eggs in the city playgrounds and dog populations suggests a potential human health hazard due to toxocariasis.

It is apparent that under the conditions of the observations recorded in this study the host-parasite relationships of the two species of snails and their respective strains of S. haematobium exhibit marked similarity in certain respects but differ in others. Higher cercarial infection rates were obtained in B. globosus than in B. truncalus at relatively low miracidial exposure levels but the daily mean cercarial outputs of each species at the same miracidial exposure level were similar. A higher frequency of production of large numbers of cercariae was recorded for infividual B. globosus than for B. truncatus. The mean cercarial prepatent periods for B. globosus and B. truncatus at a level of 7 miracidia were each 32 days, but infected B. globosus lived appreciably longer than infected B. truncatus. The hourly output of both species exposed to stimuli for the same period of time was broadly similar. Peaks of cercarial production were generally reached earlier by individual B. truncatus (2 weeks) after onset of shedding than by individual B. globosus (4–5 weeks), although erratic shedding was observed for both species.

The helminth communities of wild murid rodents were investigated in Luang Prabang and Champasak province, Lao PDR. Thirteen species of rodents (404 individuals) were infected by 19 species of parasites (2 trematode, 3 cestode, 14 nematode species). Four of the recorded helminth species (Echinostoma malayanum, Raillietina sp., Hymenolepis diminuta and H. nana) are known to cause potential zoonotic helminthiases of medical importance in the South-East Asian region. Individual helminth infection was significantly higher in the wet season. Habitat significantly influenced individual helminth species richness and individual helminth abudance, with a decrease of individual helminth species richness and individual helminth abundance from forest habitat to agricultural and human settlement habitats. The reduction of helminth diversity and abundance is discussed in relation to the ongoing increase of human influence on habitats in Lao PDR.

T helper cell (Th1 and Th2) associated responses were examined following a primary infection with the gastrointestinal nematode Heligmosomoides polygyrus in five inbred strains of mice with different resistance phenotypes. Levels of (i) mast cell protease, (ii) specific IgE, (iii) nitric oxide and (iv) specific IgG2a, as markers of Th2 and Th1 associated responses, respectively, were determined in sera and intestinal fluids and correlated with worm burdens. The ‘fast’ responder (resistant) strains SWR and SJL produced strong Th2 and Th1 associated responses respectively in a mutually exclusive fashion. The F1 hybrid (SWR×SJL) F1, showed rapid expulsion of the parasite and expressed both intense Th1 and Th2 responses, suggesting synergism between Th1 and Th2 activity in these mice. The results indicate that both Th2 and Th1 responses operate in mice following a primary infection with H. polygyrus and that each Th response may be involved to a greater or lesser degree within certain strains. Resistance to H. polygyrus was found to correlate only to the intensity of either the gut-associated mastocytosis or nitric oxide production in these strains but not to either specific IgE or IgG2a titres. Chronic infections in the ‘slow’ response phenotype mouse strains CBA and C57BL/10, were associated with both poor Th2 and poor Th1-associated responses attributed to a general parasite-mediated immunosuppression of the host immune response to infection.

Bithynids snails are a widespread group of molluscs in European freshwater systems. However, not much information is available on trematode communities from molluscs of this family. Here, we investigate the trematode diversity of Bithynia tentaculata, based on molecular and morphological data. A total of 682 snails from the rivers Lippe and Rhine in North Rhine-Westphalia, Germany, and 121 B. tentaculata from Curonian Lagoon, Lithuania were screened for infections with digeneans. In total, B. tentaculata showed a trematode prevalence of 12.9% and 14%, respectively. The phylogenetic analyses based on 55 novel sequences for 36 isolates demonstrated a high diversity of digeneans. Analyses of the molecular and morphological data revealed a species-rich trematode fauna, comprising 20 species, belonging to ten families. Interestingly, the larval trematode community of B. tentaculata shows little overlap with the well-studied trematode fauna of lymnaeids and planorbids, and some of the detected species (Echinochasmus beleocephalus and E. coaxatus) constitute first records for B. tentaculata in Central Europe. Our study revealed an abundant, diverse and distinct trematode fauna in B. tentaculata, which highlights the need for further research on this so far understudied host–parasite system. Therefore, we might currently be underestimating the ecological roles of several parasite communities of non-pulmonate snail host families in European fresh waters.

A total of 984 snails, comprising nine species, were collected from six areas in the Kafue wetlands between August and October 2003 to assess larval trematode infections. Of these, 135 (13.7%) were positive. Most trematode infections were recorded from Lymnaea natalensis (42.8%), which harboured four of the five morphologically different cercariae found. No trematodes were recovered from Bellamya capillata, Biomphalaria pfeifferi, Melanoides tuberculata, Physa acuta and Cleopatra nswendweensis. One snail (0.2%) of 416 Bulinus snails shed brevifurcate-apharyngeate distome cercariae while three (0.7%) shed amphistomes. Gymnocephalous and longifurcate-pharyngeate distome were the commonest types of cercariae recorded while xiphidiocercaria was the least common. The highest prevalence rates of F. gigantica (68.8%) and amphistomes (50.0%) in cattle (n = 101) were in Chiyasa while those in Kaleya had the lowest (9.1 and 18.2%, respectively). In most habitats, infections were recorded in both cattle and snails. Critical determinants of infection may have been the distance of settlements and/or cattle kraals, the number of animals in nearby homesteads and the presence of susceptible host snails. This study suggests that fascioliasis and amphistomiasis could be major constraints of cattle production in the Kafue wetlands because favourable factors were available to introduce and maintain the infections. It further provides a starting point for some comprehensive studies on snail-related aspects of transmission and snail host ecology in Zambia.

1. Observations carried out on four groups of sheep during the spring of 1954 are described.

2. A spring-rise in the worm-egg output was found to occur in all the groups studied.

3. The management of the animals precluded rcinfestation during the spring and, in two instances, from 8th January and 22nd, respectively.

4. Time of lambing and nutritional level appeared to influence the onset and magnitude of the spring increase.

Groups of rats, infected 7 weeks previously with Fasciola hepatica, together with appropriate control groups, were challenged either orally or intraperitoneally with 30 metacercariae. The mean worm recovery from the previously infected, orally challenged rats was significantly lower than from their respective controls (2.2 ± 1.1 worms as opposed to 9.0 ± 2.6). There was no significant difference in mean worm recovery from the previously infected, intraperitoneally challenged rats and their respective controls (5.3 ± 3.2 worms as opposed to 6.2 ± 1.9). Livers of the orally challenged group appeared to be largely free from secondary damage but considerable damage was evident in rats which received an intraperitioneal challenge. This evidence supports the view that the gut acts as an important barrier to metacercariae of a challenge infection. In a further experiment, young flukes were recovered from the gut, abdominal cavity and liver of immune and control rats 9, 18, 27, 36 and 45 h after oral challenge. It was found that fewer flukes successfuly penetrated the guts of immune rats (3%) than those of uninfected controls (13%), again pointing to the gut as a barrier to metacercariae of a challenge infection. Protective mechanisms that may oprate at the level of the gut are discussed.

Diplostomum species are economically important worldwide due to their metacercariae which parasitize the eyes of fish, in both natural and aquaculture systems. However, their striking morphological similarity, especially at the metacercarial stage, makes species separation difficult. Three closely related diplostomid metacercariae, namely Diplostomum mashonense (type 3), Tylodelphys sp. 1 and 2 (type 1 and 2, respectively), coexist in the cranial cavity of the catfish, Clarias gariepinus from Mindu dam, Lake Victoria, Msimbazi, Ruvu and Kilombero rivers. The morphometrics of these three species were analysed by discriminant function analysis to investigate the degree of variation among the populations from the five localities sampled. The first canonical functions for all visual examination plots accounted for over 50% of the between-group variability. The observed differences were mainly from measurements associated with length, indicating that these measurements are important in the description of population characteristics. Visual examination of the samples along the canonical functions showed a clear between-population differentiation. The overall random assignment of individuals into their original groups was high (97%). These extensive morphometric variations introduce doubt about the reliability of measurements in the determination of species in these trematodes, as they may lead to misidentifications.