Larval Taenia crassiceps of the ORF and KBS strains have been shown to accumulate whole 14C-Chlorella proteins in the bladder fluid. Precipitation by trichloroacetic acid removed 70% of the radioactivity indicating the 14C-Chlorella proteins had not been catabolized during movement into the bladder fluid.

To understand existence, patterns and mechanisms behind phylogenetic heritability in the geographic range size (GRS) of parasites, we measured phylogenetic signal (PS) in the sizes of both regional (within a region) and continental (within a continent) geographic ranges of fleas in five regions. We asked whether (a) GRS is phylogenetically heritable and (b) the manifestation of PS varies between regions. We also asked whether geographic variation in PS reflects the effects of the environment's spatiotemporal stability (e.g. glaciation disrupting geographic ranges) or is associated with time since divergence (accumulation differences among species over time). Support for the former hypothesis would be indicated by stronger PS in southern than in northern regions, whereas support for the latter hypothesis would be shown by stronger PS in regions with a large proportion of species belonging to the derived lineages than in regions with a large proportion of species belonging to the basal lineages. We detected significant PS in both regional and continental GRSs of fleas from Canada and in continental GRS of fleas from Mongolia. No PS was found in the GRS of fleas from Australia and Southern Africa. Venezuelan fleas demonstrated significant PS in regional GRS only. Local Indicators of Phylogenetic Association detected significant local positive autocorrelations of GRS in some clades even in regions in which PS has not been detected across the entire phylogeny. This was mainly characteristic of younger taxa.

Mannose-binding lectins were purified from flatfish spotted halibut (Verasper variegatus) serum. These lectins, which we named VVL (Verasper variegatus lectin)-α (~33 kDa) and VVL-β (~30 kDa) (VVLs), under non-reducing SDS-PAGE, were surprisingly highly concentrated in serum (1·92±0·55 mg/ml; n=5), compared with other serum lectins. Both VVLs are heterodimers comprised of 2 types of subunit via inter-subunit disulfide bonds, and one subunit of VVL-α has a N-linked sugar chain. Based on N-terminal amino acid sequences, the nucleotide sequences of one subunit of VVL cDNAs were determined by 3′- and 5′-rapid amplification of the cDNA ends. The full-length VVL subunit cDNAs contained 489 bp, encoding an open reading frame of 163 amino acids. We found that VVLs bind to an ~8 kDa ciliary surface glycoprotein (a putative agglutination/immobilization antigen that we reported previously) of the fish parasite Neobenedenia girellae, and agglutinate this parasite in vitro.

A characteristic feature of infections with the nematode parasite of mice Heligmosomoides polygyrus, is a marked IgG1 hypergammaglobulinaemia. A possible source for this immunoglobulin has recently been demonstrated, through evidence that H. polygyrus adult worm homogenate (AWH) can induce the in vitro production of non-specific IgG1 from mouse lymphocytes. To determine the interactions between this immunoglobulin and the parasite, the ability of IgG1 to bind to AWH of H. polygyrus was investigated. Protein (Western) blotting indicated that mouse monoclonal antibodies are able to bind non-specifically to selected parasite antigens. Furthermore, by binding H. polygyrus adult worm homogenate to cyanogen bromide (CNBr)-activated Sepharose CL-4B, an affinity column was prepared which could be used to efficiently purify mouse IgG1 monoclonal antibodies. These antibodies were eluted from the affinity column and still retained their original specificity. These results indicate that H. polygyrus not only induces the production of non-specific IgG1 by the host, it can also bind this immunoglobulin to its own specific proteins. Thus, it is possible that IgG1 produced during a primary infection with H. polygyrus may not entirely benefit the host.

The efficiency of assimilation of carbon and nitrogen by Littorina saxatilis, as calculated from the carbon and nitrogen content of food and faeces, showed that the efficiency of snails infected with rediae of Cryptocotyle lingua did not differ significantly from that in non-infected snails.

Similarly, the rate of ingestion and the rate of assimilation of infected snails did not differ significantly from those of non-infected snails.

It is suggested that this harmonious relationship reflects the longterm strategy of Cryptocotyle lingua infections.

Parasites of the genus Hepatocystis are close relatives of Plasmodium that frequently infect epauletted fruit bats across West and East Africa. Our understanding of susceptible hosts and prevalence of infection of Hepatocystis remains fragmented. Non-invasive sampling of bat assemblages in representative habitats critically contribute to haemosporidian parasite distribution maps. Here, we report on a survey of Hepatocystis parasite infections in bats undertaken over two consecutive years in a protected area in Nigeria, where prevalence and diversity of bat-infecting haemosporidian parasites have not been studied. Microscopic examination of blood films in combination with PCR detection and sequencing revealed Hepatocystis infections with prevalences of 25% and 42% in the closely related epauletted fruit bats Epomophorus sp. and Micropteropus pusillus. For the first time, mature Hepatocystis gametocytes were identified in one Egyptian fruit bat (Rousettus aegyptiacus). This novel host record was confirmed by parasite and host genotyping and suggests that Hepatocystis parasites have a broader host distribution in African fruit bats than currently known.

Foleyella confusa sp.nov. is described from Rana limnocharis on Luzon, near Manila. It differs from F. duboisi (Gedoelst) in arrangement and number of anal papillae, in spicule size in relation to length of body, and in overall size. Icosiella hoogstraali sp.nov. from Rana macrodon on Palawan differs from others in the genus in having a left spicule 1·955 mm long and a single preanal papilla. Gnathostoma spinigerum and Cosmocerca japonica are also reported.

We thank Dr Roy C. Anderson, University of Guelph, for reading the manuscript and offering his comments on it.

The authors wish to acknowledge the field support by Dr D. S. Rabor, Department of Biology, Silliman University, Dumaguete City, Negros Oriental, Republic of the Philippines, and the technicians of the Parasitology Department of Naval Medical Research Unit no. 2 for general assistance in obtaining and examining hosts.

Initial work for this study was supported by funding under Public Law 480, Section 104 (c), by funds provided by the Bureau of Medicine and Surgery, Navy Department Work Unit MR 005·20–0098, and by Contract No. NR 103–690/N0014–66-C 0094, between the Office of Naval Research, Department of the Navy, and the Southwest Foundation for Research and Education.

Final efforts were sponsored by Department of the Army, Contract No. DADA 17–68–C–8094.

Intraperitoneal injection of cercariae into pristane (2, 6, 10, 14 tetramethyl pentadecane)-primed Balb/c mice led to greatly diminished numbers of portal and peritoneal worms compared with untreated mice. Schistosomula taken from the peritoneal cavity of pristane-primed mice carried globules of pristane on their surfaces, were contracted and were permeable to Trypan blue. Pristane globules bound also to adult worms in vitro and in vivo causing rapid damage to the surface membrane. Hydrophobic compounds other than hydrocarbons either bound without causing gross damage, or did not bind to the adult worms. 51Cr release studies showed that pristane had no effect on the permeability of human erythrocytes, while causing significant release from both schistosomula and adult worms. The binding of hydrocarbon globules to a variety of other parasites did not occur. The binding of n-[1-14C]hexadecane to adult Schistosoma mansoni was significantly decreased by extraction of the parasite with organic solvents or treatment with staphylococcal δ toxin, which interacts with phospholipids in the membrane. Possible mechanisms of damage of the parasite by the hydrocarbons are discussed.

A coccidium belonging to the family Adeleidae was discovered in the mid-gut cells of Tipula paludosa. A new genus Rasajeyna and a new species nannyla are established because this pathogen differs from previously described coccidia. A diagnosis of R. nannyla is given.

The endogenous phase of R. nannyla is restricted to larvae. The oocysts, which are the external phase of the parasite, are swallowed by the leatherjackets and excyst in the anterior mid-gut. The sporozoites, 36·5 µm (± 5·4 µm, 95% confidence limits) long, 15·7 µm (± 1·8 µm, 95% confidence limits) wide, each containing a refractile body, enter the anterior mid-gut cells where the 1st schizogony occurs. The refractile bodies are retained during the early nuclear divisions. The sausage-shaped merozoites, 28·2 µm (± 4·3 µm, 95% confidence limits) long, 7·1 µm (± 0·9 µm, 95% confidence limits) wide, with posterior nuclei exhibit three distinct types of movement. (a) An active flexion of the body which is thought to occur during the intracellular phase. (b) A flicking action by both ends of the body. This is thought to occur during the free phase. (c) A spiralling motion which is thought to aid the entry of the merozoite into the cells.

The nucles of the intracellular merozoite divides several times, forming a multinucleate body. The merozoites of the 2nd schizogony form in groups at the poles of the schizont. The merozites are indistinguishable from each other until after a period of growth has ensued, when they are differentiated as macro- and microgametocytes. The pear-shaped macrogamete 44·3 µm (± 4·5 µm, 95% confidence limits) long, 21·6 µm (± 3·2 µm, 95% confidence limits) wide, which contains a crescent-shaped structure in the nucleus. The microgametocyte grows to 40·3 µm (± 2·7 µm, 95% confidence limits) long, 16·7 µm (± 1·5 µm, 95% confidence limits) wide and then attaches itself lengthwise to the macrogamete. A membrane is then secreted around both partners. Nuclear division produces 4 microgametes, one of which fertilizes the female. The 1st and 2nd oocyst membranes are deposited before cytoplasmic shrinkage and meiosis. The zygote is 44·6 µm (± 4·2 µm, 95% confidence limits) long and 33·7 µm (± 4·1 µm, 95% confidence limits ) wide. Cytoplasmic condensation around the nuclei forms the sporoblasts which mature into sporocysts each containing 1 sporozoite. The zygote may be expelled from the larvae at any juncture after fertilization.

The escape kinetics from the anterior midgut (AM) of Trypanosoma cruzi during the initial steps of infection was assessed in Triatoma infestans, as well as its ability to survive migration in the digestive tract of the vector. All the four strains evaluated survived and reached variable parasite densities. After 49–50 days, YuYu [discrete typing units (DTU) I] strain reached the highest parasite numbers in the rectum followed by Bug (DTU V), CL-Brener (DTU VI) and Dm28c (DTU I). All strains accomplished metacyclogenesis. Bug strain reached the highest numbers of metacyclic trypomastigotes followed by YuYu and CL-Brener/Dm28c. A remarkable parasite reduction in the AM for Bug strain, but not Dm28c was noticed at 72 h of infection. In the posterior midgut + rectum high densities of parasites from both strains were detected at this period indicating the parasites crossed the AM. For Dm28c strain, in infections initiated with trypomastigotes, parasites left AM faster than those starting with epimastigotes. In conclusion, T. cruzi strains from different DTUs were able to infect T. infestans reaching variable parasite densities. The kinetics of migration in the digestive tract may be affected by strain and/or the evolutive form used for infection.

It is well known that the defence reactions of insects to metazoan parasites are principally cellular rather than humoral; and it has recently been shown that the habitual parasitoids of an insect have means of resisting or avoiding the defence reactions of their host (Salt, 1968). Those two findings suffest that it may be necessary to re-examine the situation with regard to protozoan parasites, including some genera for which insects act as vectors between vertebrate hosts. Two examples will serve to draw attention to the problems involved.

Proteomics has come to the forefront in the post-genomic era. The ability to compare and identify proteins expressed in a particular cell type under specific physiological or pathological states requires a range of technologies, including separation of complex protein or peptide mixtures, densitometry-based or isotope-coded methods for comparison of multiple proteomes, and mass spectrometric methods for identification of individual low abundance proteins. Although an emergent technology, thus far, proteomics has provided new perspectives on many problems in biomedical science. In parasitology, proteomics has been used to answer specific biological questions relating to survival and development, and also to identify candidates for vaccines. Here, we describe an ongoing research programme in which proteomics is being used to identify potential vaccine candidates for the bovine lungworm, Dictyocaulus viviparus. This work is focusing on antibody responses to the adult parasite excretory/secretory (ES) products, with selection of candidate antigens based on differential screening with serum from immune versus non-immune animals to simplify the proteome and the ensuing analytical challenges. Thus far, we have identified seven candidate proteins using this strategy. Of these, one protein showed significant identity to a previously cloned gene from D. viviparus, whilst the other six proteins have shown no significant identities. Isolation of further peptide sequences is now warranted to facilitate cloning of the genes encoding these antigens.

Myxozoans have been successfully used as tags for fish stock identification around the world. However, few studies using myxozoan tags have been carried out in the Southern Atlantic, a region with complex oceanography that constitutes a potentially suitable scenario for testing the utility of myxozoans as indicators. Its usefulness was tested using six samples of Merluccius hubbsi in two different regions of the Argentine Sea. Generalized linear models were performed to assess the effects of fish size and sex, and year and region of capture and selected using the Information Theoretic approach. Three myxozoan species were recorded: Kudoa rosenbuschi, Myxoproteus meridionalis and Fabespora sp. Results of modelling species individually showed differential capabilities for detecting geographical population structure at different spatial scales, with K. rosenbuschi and Fabespora sp. allowing the discrimination of northern and southern stocks, but Fabespora sp. also as a promissory indicator of intrapopulation sub-structure due to different migratory routes during non-reproductive periods. This work confirms that myxozoans offer a set of suitable markers at different spatial scales, which can be selected individually or in any combination, depending on the geographical extent of the study, constituting tools adaptable to the objectives of further research on fish population structure.

1. Cercaria pekinensis, a new cystocercous cercaria, is described.

2. The excretory system of the developed cercaria consists of a bladder, a drainage channel through the tail and a pair of anterior collecting tubules, each of which receives eight main (tertiary) branches. Each branch is composed of 2 × 4 × 4 units. The posterior-most branch cares for the drainage of the tail, including the corresponding flapper.

3. A study of representative stages in development shows that the common denominator of the excretory system is α + β, while the pattern of the developed cercaria is expressed by 4 (α)2 + 4 (β)2.

4. The fundamental pattern of tie cercaria is likewise found in the sporocyst.

5. These data have a significant bearing on the application of mathematics to the problems of growth and development.

Trypanosomiasis is caused by Trypanosoma species which affect both human and animal populations and pose a major threat to developing countries. The incidence of animal trypanosomiasis is on the rise. Surra is a type of animal trypanosomiasis, caused by Trypanosoma evansi, and has been included in priority list B of significant diseases by the World Organization of Animal Health (OIE). Control of surra has been a challenge due to the lack of effective drugs and vaccines and emergence of resistance towards existing drugs. Our laboratory has previously implicated Heat shock protein 90 (Hsp90) from protozoan parasites as a potential drug target and successfully demonstrated efficacy of an Hsp90 inhibitor in cell culture as well as a pre-clinical mouse model of trypanosomiasis. This article explores the role of Hsp90 in the Trypanosoma life cycle and its potential as a drug target. It appears plausible that the repertoire of Hsp90 inhibitors available in academia and industry may have value for treatment of surra and other animal trypanosomiasis.

The present paper deals with material examined since the revision of the family (Theodor, 1967) was sent to the press. Material was sent by Mr F. R. Allison from Ghana, by Dr D. Minter, Mr T, S Jones and Mr J. C. Cunningham from East Africa and by Dr F. Zumpt from South Africa and other localities in Africa. The material collected by the Noona Dan Expedition to the Bismarck Archipelago and the Philippines (1961, 1962) was examined. The collection of Nycteribiidae in the Museo Civico di Storia Naturale in Genoa was examined and several new species were found among the material. The types of Stylidia euxesta Speiser in the collection proved different from the species considered as 8. euxesta in the past and to consist of two species. The types of S. euxesta are redescribed.

1. Megasolena estrix Linton 1910 has been incorrectly classified in the Allocreadiidae.

2. The possession of two pairs of longitudinal lymph vessels, a remarkable hermaphroditic sac as well as other minor characters indicate relationship to the Paramphistomidae.

3. Hapladena Linton 1910 possesses these same characters and is considered related to Megasolena.

4. These characters are considered to be of more fundamental taxonomic value than the position of the acetabulum.

5. A new subfamily, Megasoleninae, of the family Opistholebetidae is named and described.

During a series of experiments on the ecology of Nematodirus battus observations were made on the uptake of water by eggs containing third-stage larvae. It was found that, as they approached hatching, the water content of the larvae increased markedly, then fell immediately after they escaped from the shell. The method of measuring the water content, using interferometry, is also described.

Schistosomiasis, commonly known as bilharzia, is a parasitic disease prevalent in Africa, Asia and South America. The majority of the cases occur in Sub-Saharan Africa where schistosomiasis is a major public health problem impacting on child health and development as well as adult health when infections become chronic. Control of schistosomiasis is by treatment of infected people with the antihelminthic drug praziquantel. Current schistosome control programmes advocated by the World Health Assembly in 2001 are aimed at regular school-based integrated deworming strategies in order to reduce development of severe morbidity, promote school health and to improve cognitive potential of children. Several countries in Africa have now embarked on national scale deworming programmes treating millions of children exposed to schistosomiasis in endemic areas without prior diagnosis of infection through mass drug administration programmes. Implementing such control programmes requires a concerted effort between scientists, policy makers, health practitioners and several other stake holders and of course a receptive community. This paper considers the contributions to global schistosome control efforts made by research conducted in Zimbabwe and the historical context and developments leading to the national schistosomiasis control programme in Zimbabwe giving an example of Getting Research into Policy and Practice.