Most attempts to culture adult digeneans in vitro are unsuccessful. Even progenetic digeneans typically fail to produce infective eggs in axenic culture. However, metacercariae of Microphallus turgidus grown in vitro mature into adults and release eggs infective to the hydrobiid snail Spurwinkia salsa. The objectives of the present study were to verify the reproducibility of the M. turgidus culture protocol, to define optimal culture conditions for M. turgidus further, and to investigate why the parasite can be grown successfully in the absence of the definitive host. In the original cultivation protocol, excysted M. turgidus metacercariae from grass shrimp (Palaemonetes pugio) were incubated overnight in a conical-bottom centrifuge tube containing Hank's balanced salt solution and then cultivated in flat-bottom culture plate wells containing RPMI-1640 plus 20% horse serum. The gas phase was air. Worms cultured under this protocol consistently deposited eggs infective to snails. Worms grown in anaerobic conditions deposited few eggs, and those cultured in a gas phase of 5% CO₂ survived longer and produced more eggs than those cultured in air. However, snails were less likely to become infected when fed eggs deposited by worms cultured in 5% CO₂. Additionally, worms incubated with conspecifics in conical-bottom tubes prior to cultivation were more likely to be inseminated than worms incubated in flat-bottom culture wells; the highest percentages of inseminated worms occurred when metacercariae were incubated 24 hr in conical-bottom tubes at a density of 50 worms/tube and at a temperature of 37 C. Worms incubated in the absence of conspecifics were not fertilized and failed to produce infective eggs.

Metacercariae of Panopistus pricei (Brachylaimidae) are common parasites of 2 species of terrestrial gastropods (Neohelix albolabris; Webbhelix multilineata) in southeastern Nebraska. Field data were collected to determine if individuals of N. albolabris and W. multilineata function as ecologically equivalent second intermediate hosts of P. pricei along a transect on the western edge of the Missouri River. Metacercariae were recovered and measured from samples of 30 snails of each species collected at each of 6 sites; whole kidneys from snails of both species were examined to quantify microhabitat use. Microhabitat use of P. pricei did not differ between host species; in both N. albolabris and W. multilineata, metacercariae were concentrated in the primary ureter and occurred throughout the kidney proper. Prevalences and mean abundances did not differ between host species at any site, nor did the relationship between parasite abundance and host size. Prevalences and mean abundances across sites were positively correlated between host species. At 2 sites, demographics of metacercariae differed between host species, suggesting short-term differences in the history of encounters with cercariae in the environment and differences in transmission to shrew definitive hosts. Overall, N. albolabris and W. multilineata appear to be equivalent and required second intermediate hosts of P. pricei in the area studied.

This study analyzed the variation of the parasite infracommunities and their relationship with the diet and spatial distribution of the clingfish Sicyases sanguineus during its ontogeny. In total, 154 clingfish were collected from the intertidal and the upper subtidal zone of Pacific Ocean along the central Chilean coast. A wide range in body length (1.4–34.5 cm) was observed, including juvenile and adult specimens. Eleven parasite species were found in the clingfish, i.e., 2 Copepoda, 2 Hirudinea, 1 Monogenea, 5 Digenea, and 1 Cestoda. The prevalence, total abundance, Brillouin's diversity index, and the infracommunity species richness increased with fish body length. The parasite communities, the diet, and the spatial distribution changed during clingfish ontogeny, specifically between juveniles (<20 cm body length [BL]) and adults (>20 cm BL). When fish reached a 20-cm BL, a considerable increment in abundance and species richness of parasites was observed; this coincided with an increase in the number of prey items in the diet and with a change of the fish from the intertidal into the subtidal zone. Therefore, the ontogeny of S. sanguineus is important for the variation of parasite infracommunities, which also was associated with dietary and spatial distribution shifts of this fish.

Six new and 1 previously described species of Pseudorhabdosynochus (Diplectanidae) are described and/or reported from the gill lamellae of 5 serranid (Perciformes) fish species from the Pacific waters in Guerrero State of Mexico and Panama City, Panama. These species are Pseudorhabdosynochus guerreroensis n. sp. from the Pacific mutton hamlet Alphestes inmaculatus Breder (type host), rivulated mutton hamlet Alphestes multiguttatus (Günther), and spotted grouper Epinephelus analogus Gill from Mexico; Pseudorhabdosynochus urceolus n. sp. from the Pacific graysby Cephalopholis panamensis (Steindachner) from Taboga Island in Panama; Pseudorhabdosynochus spirani n. sp. from the starry grouper Epinephelus labriformis (Jenyns) from Mexico and the Perlas Archipelago and Taboga Island in Panama; Pseudorhabdosynochus fulgidus n. sp. from E. labriformis from Mexico and the Perlas Archipelago and Taboga Island (type locality) in Panama; Pseudorhabdosynochus tabogaensis n. sp. from E. labriformis from Mexico and the Perlas Archipelago and Taboga Island (type locality) in Panama; Pseudorhabdosynochus anulus n. sp. from E. labriformis from Mexico and Taboga Island (type locality) in Panama; and Pseudorhabdosynochus amplidiscatum (Bravo-Hollis, 1954) Kritsky and Beverley-Burton, 1986 from E. analogus and E. labriformis from Mexico and the Perlas Archipelago and Taboga Island in Panama. All new species are mainly distinguished from other species of the genus by the shape and size of the sclerotized vagina and haptoral structures. The present specimens of Alphestes, Cephalopholis, and Epinephelus spp. represent new host records and Panama represents a new geographic record for species of Pseudorhabdosynochus. The apparent common feature supporting a close similarity of these diplectanids is a single, secondary ejaculatory bulb with thickened wall.

The furcocystocercous cercariae of the digenetic trematode, Proterometra macrostoma, possess a tail chamber into which their distome body withdraws prior to emergence from their snail intermediate host. The process of distome retraction and the conditions that trigger it in this species are not clear. The objectives of the present study were (1) to describe the retraction process in P. macrostoma; (2) to assess whether osmolality affects cercarial retraction; (3) to evaluate the effect of selected ions on retraction; and (4) to compare the swimming effectiveness of naturally ( =  in vivo) retracted versus in vitro retracted cercariae. Retraction of the cercaria body into its tail chamber required only 2 min or less once initiated. The process began with the development of a chamber within the anterior end of the worm's tail. The chamber's lip advanced in a pulsating motion over the stationary distome. Retraction was completed with the constriction and fusion of the chamber lip once it passed over the anterior end of the distome, sealing the latter within the tail chamber. There was a significant difference in the proportions of cercariae with bodies retracted into tails, bodies not retracted, and bodies separated from tails in artificial pond water (APW) versus artificial snail water (ASW). A greater number of cercariae withdrew into their tail chambers in ASW (59/124; 47.6%) than in APW (21/124; 16.9%). In APW, more bodies separated from their tails (24/124; 19.4%) than in ASW (3/124; 2.4%). In both solutions (APW: 63.7%  =  79/124; ASW: 50%  =  62/124), a majority of cercariae never retracted. In APW, 76.2% of distomes retracting into their tails did so within the first 5 min compared to only 30.5% in ASW. There was no significant difference in the proportions of cercariae with bodies retracted into tails, bodies not retracted, and bodies separated from tails based on isosmotic replacement of individual ions, i.e., Na , K , Ca , or Mg , in ASW with Li . There was also no significant difference in the vertical swimming burst distance in cercariae whose bodies were initially retracted into their tails in vitro versus in vivo.

There is a lack of information about the seroepidemiology of T. gondii infection in the general population of Durango City, Mexico. Anti–Toxoplasma gondii IgG and IgM antibodies were sought in 974 inhabitants in Durango City, Mexico with the use of enzyme-linked immunoassays. in total, 59 (6.1%) of 974 participants (mean age 37 ± 16.1 yr) had IgG anti–T. gondii antibodies. Twenty (2.1%) of them also had IgM anti–T. gondii antibodies. IgG levels of 13–99, 100–150, and >150 International Units (IU)/ml were found in 14 (23.7%), 3 (5.1%), and 42 (71.2%) anti–T. gondii IgG-positive participants, respectively. Prevalence of infection increased with age (P < 0.05), and was significantly lower in participants born in Durango State than those born in other Mexican states (P < 0.01). Toxoplasma gondii infection was significantly associated with consumption of boar meat (adjusted odds ratio [OR]  =  3.02; 95% confidence interval [CI]: 1.49–6.13), and squirrel meat (adjusted OR  =  2.18; 95% CI: 1.17–4.09). in addition, infection was negatively associated with travel abroad (adjusted OR  =  0.42; 95% CI: 0.23–0.77), and salami consumption (adjusted OR  =  0.57; 95% CI: 0.32–0.99). This is the first report of seroprevalence and contributing factors for T. gondii infection in general population in Durango City, and of an association of the consumption of boar meat with T. gondii infection. This study provides a basis for the design of successful preventive measures against T. gondii infection.

Sera from 77 cattle and 61 pigs from herds of Campos dos Goytacazes and neighborhood, north of Rio de Janeiro state, Brazil, were analyzed for the presence of antibodies anti–Toxoplasma gondii via ELISA. The seropositivity was confirmed at 49.4% (38 of 77) for cattle and at 11.5% (7 of 61) for pigs. Pigs bred under free-ranging systems presented with 20.6% (7 of 34) seropositivity and no pigs bred under indoor systems were positive (n  =  27). The seropositivity verified for cattle and pigs confirmed the extensive distribution of the parasite in this region. In the face of these data, we discuss the potential risk for human infection by consumption of raw or undercooked meat in this geographic region of Brazil. This is the first report of seropositivity for anti–T. gondii antibodies in cattle in the north of Rio de Janeiro State, Brazil.

Mammalian immune responses to Trypanosoma brucei infection are important to control of the disease. In rats infected with T. brucei gambiense (Wellcome strain; WS) or T. brucei brucei (interleukin-tat 1.4 strain [ILS]), a marked increase in the number of macrophages in the spleen can be observed. However, the functional repercussions related to this expansion are not known. To help uncover the functional significance of macrophages in the context of trypanosome infection, we determined the mRNA levels of genes associated with an increase in macrophage number or macrophage function in WS- and ILS-infected rats and in cultured cells. Specifically, we assayed mRNA levels for macrophage colony stimulating factor (M-CSF), granulocyte macrophage colony stimulating factor (GM-CSF), and macrophage migration inhibitory factor (MIF). Upregulation of GM-CSF and MIF mRNA levels was robust in comparison with changes in M-CSF levels in ILS-infected rats. By contrast, upregulation of M-CSF was more robust in WS-infected rats. The phagocytic activity in macrophages harvested from ILS-infected rat spleens, but not WS-infected spleens, was higher than that in macrophages from uninfected rats. These results suggest that macrophages of WS-infected rats change to an immunosuppressive type. However, when WS or ILS is cocultured with spleen macrophages or HS-P cells, a cell line of rat macrophage origin, M-CSF is upregulated relative to GM-CSF and MIF in both cell types. Anemia occurs in ILS-, but not WS-infected, rats. Treatment of spleen macrophages or HS-P cells cocultured with ILS with cobalt chloride, which mimics the effects of anemia-induced hypoxia, led to downregulation of M-CSF mRNA levels, upregulation of GM-CSF and MIF, and an increase in phagocytic activity. However, the effect of cobalt chloride on spleen macrophages and HS-P cells cocultured with WS was restricted. These results suggest that anemia-induced hypoxia in ILS-infected rats stimulates the immune system and activates macrophages.

Squids are especially frequent as paratenic hosts of helminth parasites, particularly to those that have elasmobranchs and mammals as final hosts. Among those parasite species, anisakid nematode larvae and cestode plerocercoids are most effectively transferred through the trophic chain by oegopsid squids. A total of 439 short-finned squids, Illex coindetii (245 males, 190 females and 4 unsexed) were sampled in the central part of the eastern Adriatic Sea in order to assess their helminth component community and parasite dynamics with respect to host sex, maturity, seasonality, and feeding behavior. Two larval helminths were isolated, i.e., larvae of Anisakis pegreffii, characterized by molecular tools at the species level, and plerocercoids of Phyllobothrium sp., with prevalences of 30.5% and 2.3%, respectively. Highly significant seasonal variation in diet consumption, congruent with seasonal variation in anisakid intensity, was observed, underlining the tight role of squid prey in the trophic transmission of parasite. Likewise, the highest helminth prevalence and intensity of infection was recorded in autumn, when the fish prey, mostly Maurolicus muelleri, comprised the greatest proportion of diet. This helped to assign the Adriatic broadtail shortfin squid not as a first, but as a second, paratenic host for the anisakid, unlike as suggested previously. The presence of larval A. pegreffii confirms its previously reported zoogeographical distribution in the Mediterranean and Adriatic Seas. The presence of 2 helminths in I. coindetii describes the feeding patterns of the squid, as well as clearly defined and coevolved predator–prey relationships.

Babesia microti-like parasites have been reported to infect captive non-human primates (NHPs). However, studies on the prevalence of Babesia spp. in free-ranging NHPs are lacking. This investigation aimed at determining the prevalence of B. microti in wild-caught Kenyan NHPs. In total, 125 animals were studied, including 65 olive baboons (Papio cynocephalus anubis) and 60 African green monkeys ([AGMs] Chlorocebus aethiops). Nested polymerase chain reaction targeting Babesia β-tubulin genes was used to diagnose infection prevalence. Results indicated a prevalence of 22% (27/125) B. microti infection in free-ranging NHPs in Kenya. There was no statistically significant difference in B. microti infection prevalence between baboons and AGMs or male and female animals. This is the first report of the presence and prevalence of B. microti in free-ranging Kenyan NHPs.

Seasonal occurrence of Opechona pyriforme metacercariae in the Eirene tenuis population from Laguna Madre, Mexico was analyzed in zooplankton samples collected in October 1997 and January, May, and July 1998. Eirene tenuis medusae were present in May, July, and October, although parasites were found only in October and July samples. Host population density was positively correlated with both surface water temperature and salinity. Total sample prevalence was 3.74%, mean abundance of the parasite was 0.06, and intensity of infection ranged between 1 and 59 metacercariae/host. Prevalence differed significantly among seasons, while intensity of infection did not. Parasite distribution was found to be highly aggregated. Although O. pyriforme infected hydromedusae of all sizes, prevalence was higher in sizes above 2.11 mm umbrella diameter. Additionally, a tendency towards increasing intensity of infection values with increasing umbrella diameter of medusae was observed. This is the first record of E. tenuis as a second intermediate host of O. pyriforme, as well as the first record of this helminth in the Gulf of Mexico.

Schistosomiasis is endemic in over 70 countries, in which more than 200 million people are infected with the various schistosome species. Understanding the physiological processes underlying key developmental events could be useful in developing novel chemotherapeutic reagents or infection intervention strategies. Calmodulin is a small, calcium-sensing protein found in all eukaryotes and, although the protein has been previously identified in various Schistosoma mansoni stages and implicated in egg hatching and miracidia transformation, few molecular and functional data are available for this essential protein. Herein, we report the molecular cloning, expression, and functional characterization of calmodulin in the miracidia and primary sporocyst stages of S. mansoni. Two transcripts, SmCaM1 and SmCaM2, were cloned and sequenced, and a recombinant SmCaM1 protein was expressed in Escherichia coli and used to generate anti-CaM antibodies. The 2 protein sequences were highly conserved when compared to other model organisms. The alignment of the predicted proteins of both SmCaM1 and SmCaM2 exhibited 99% identity to each other and 97–98% identity with mammalian calmodulins. Analysis of steady-state transcript abundance indicate that the 2 calmodulin transcripts differ in their stage-associated expression patterns, although the CaM protein isotype appears to be constitutively expressed during early larval development. Application of RNAi to larval parasites results in a “stunted growth” phenotype in sporocysts with 30 and 35% reduction in transcript abundance for SmCaM1 and SmCaM2, respectively, and a corresponding 35% reduction in protein level after incubation in double-stranded RNA. Differential expression of CaM transcripts during early larval development and a growth defect-inducing effect associated with partial transcript and protein inhibition as a result of RNAi suggest a potentially important role of calmodulin during early larval development.

We have evaluated the possible mechanisms of liver fibrosis caused by Fasciola hepatica in an animal model and in culture using immortalized human stellate cells. Liver biopsies of F. hepatica-infected rats were performed at wk 8 and 16. Serum-starved LX-2 cells, a human stellate cell line, were exposed to increasing concentrations of Fas2 antigen. The expression of key fibrosis-related genes was evaluated by qRT-PCR. There was a significant correlation between fibrogenic gene expression and both intensity and duration of infection. LX-2 cells exposed to Fas2 showed progressively increased expression of mRNAs for Collagen I, alpha-smooth muscle-actin, platelet-derived growth factor beta receptor, and tissue inhibitor of metalloproteinase II; inhibition of Fas2 cysteine proteinase activity by E-64 abrogated these increases, suggesting that the protease activity of Fas2 is involved in fibrogenic stimulation. In summary, F. hepatica infection is associated with up-regulation of mRNAs associated with hepatic fibrogenesis in vivo and in activated hepatic stellate cells.

Anemia generated from African trypanosome infection is considered an important symptom in humans and in domestic animals. In order to recover from anemia, the process of erythropoiesis is essential. Erythropoiesis is affected by erythropoietin (EPO), an erythropoietic hormone, supplying iron and inflammatory and proinflammatory cytokines. However, the role of these factors in erythropoiesis during African trypanosome infection remains unclear. In the present study, we analyze how erythropoiesis is altered in anemic Trypanosoma brucei brucei (interleukin-tat 1.4 strain [ILS])-infected rats. We report that the packed cell volume (PCV) of blood from ILS-infected rats was significantly lower 4 days after infection, whereas the number of reticulocytes, as an index of erythropoiesis, did not increase. The level of EPO mRNA in ILS-infected rats did not increase from the third day to the sixth day after infection, the same time that the PCV decreased. Kidney cells of uninfected rats cultured with ILS trypanosome strain for 8 hr in vitro decreased EPO mRNA levels. Treatment of both ILS and cobalt chloride mimicked hypoxia, which restrained the EPO-production–promoting effect of the cobalt. Messenger RNA levels of β-globin and transferrin receptor, as markers of erythropoiesis in the bone marrow, also decreased in ILS-infected rats. Levels of hepcidin mRNA, which controls the supply of iron to the marrow in liver, were increased in ILS-infected rats; however, the concentration of serum iron did not change. Furthermore, mRNA levels of interleukin-12, interferon-γ, tumor necrosis factor-α, and macrophage migration inhibitory factor in the spleen, factors that have the potential to restrain erythropoiesis in bone marrow, were elevated in the ILS-infected rats. These results suggest that ILS infection in rats affect erythropoiesis, which responds by decreasing EPO production and restraining its function in the bone marrow.

Skrjabinodon aspercaudus n. sp. from the large intestine of Pholidobolus montium (Gymnophthalmidae) from Ecuador is described and illustrated. Skrjabinodon aspercaudus represents the 29th species assigned to the genus and the 6th species from the neotropical region. The new species differs from all other species assigned to Skrjabinodon by the presence of small bosses on the surface of the tail filament of both males and females. In addition to the new species, P. montium harbored the cestode, Cairaella henrii, and third-stage larvae of a species of Physaloptera.

The genus Southwellina is composed of 3 described species, i.e., S. hispida (the type species), S. dimorpha, and S. macracanthus. All 3 are endoparasites of fish-eating birds that have worldwide distributions. Morphologically, the genus is characterized by possessing a short and compact trunk, 2 fields of spines in the anterior region of the trunk (in at least 1 sex), a short cylindrical proboscis (sometimes with a swollen region armed with numerous longitudinal rows of hooks), a double-walled proboscis receptacle, and 4 tubular cement glands in males. In the current study, specimens identified as S. dimorpha were collected from Eudocimus albus (white ibis), the type host from the Gulf of Mexico. Sequences of 2 nuclear genes (small subunit [SSU] and long subunit [LSU] ribosomal DNA) and 1 mitochondrial gene (cytochrome c oxidase subunit 1 [cox 1]) of S. dimorpha and S. hispida were obtained and used to reconstruct the phylogenetic relationships of both species with respect to published sequences of 11 species representing 6 genera of Polymorphidae. Maximum parsimony (MP) and maximum likelihood (ML) analyses of the concatenated data set (SSU LSU cox 1) were identical in depicting Southwellina as paraphyletic, indicating that the genus should be revised. The MP and ML trees identified S. hispida as a sister to Polymorphus brevis, whereas S. dimorpha was a sister to Hexaglandula corynosoma. Morphologically, S. dimorpha is distinct from H. corynosoma, which is characterized by a short trunk with 1 field of spines in the anterior part of the trunk in both genders, and males with 6 tubular cement glands. The genetic divergence estimated from a concatenated data set between 2 isolates of S. hispida and S. dimorpha ranged from 10.7 to 11.0%. This range of genetic divergence is similar to that found among other genera of Polymorphidae, which extends from 6.0 to 12.0%. Southwellina dimorpha differs from S. hispida in the shape of the proboscis and the presence of 1 field of spines (S. dimorpha) versus 2 fields (S. hispida) on the anterior region of the trunk in females. Based on the phylogenetic position of S. dimorpha within Polymorphidae, coupled with levels of genetic divergence and, more importantly, the morphological and ecological (host specificity) differences, we propose the erection of a new genus to accommodate S. dimorpha.

Hepatozoon parasites were examined for the first time in reptiles from the Seychelles Islands. Although both prevalence and intensity were low, Hepatozoon species were detected in individuals from 2 endemic species, the lizard Mabuya wrightii and the snake Lycognathophis seychellensis. This was confirmed using visual identification and through sequencing part of the 18s rRNA gene. Phylogenetic analysis indicates that the Hepatozoon on the Seychelles form a monophyletic lineage, although more data are clearly needed to stabilize estimates of relationships based on this marker.

A new species of arhythmacanthid acanthocephalan, Heterosentis martini n. sp., parasitic in the Argentinean sandperch Pseudopercis semifasciata (Cuvier) (Perciformes, Pinguipedidae) from the coasts of Argentina is described. Heterosentis martini n. sp. differs from all congeneric species by having 10 longitudinal rows of hooks in the proboscis, each with 7–8 hooks, consisting of 1 medium apical and 3 larger sub-apical hooks with root, and 3–4 smaller, basal, curved hooks with rudimentary roots and spines in both ventral and dorsal regions of the body. The most similar species, Heterosentis heteracanthus (Linstow, 1896) Van Cleave, 1931, and Heterosentis brasiliensis Vieira, Felizardo and Luque, 2009, also have 10 longitudinal rows of hooks, but H. heteracanthus differs from the new species by having only 3–5 (more frequently 4) hooks in each row, with only the anterior hook large and bearing a developed root. Heterosentis brasiliensis differs from the new species by possessing 2 sub-apical hooks in each row (instead of 3), similar body length but shorter proboscis, and trunk spines restricted to the ventral surface of body.

Theileria sergenti is a tick-borne parasite found in many parts of the world. The major piroplasm surface protein (MPSP), a conserved protein in all Theileria species, has been used as a marker for epidemiological and phylogenetic studies of benign Theileria species. In this study, Chinese species of T. sergenti were characterized by allele-specific polymerase chain reaction (PCR) and DNA sequence analysis of the MPSP gene. Using universal or allele-specific primer sets for PCR amplification of the MPSP gene, 98 of 288 cattle blood samples, collected from 6 provinces in China, were found to be positive. Among the positive samples, only 3 allelic MPSP gene types (Chitose [C]-, Ikeda [I]-, and buffeli [B]-type) were successfully amplified. Moreover, the results revealed that the majority of the parasites sampled in this study were C- and I-type (prevalence of 84 and 69%, respectively), whereas the B-type was less common (prevalence of 36%). Co-infections with C-, I-, and B-type T. sergenti also were found. An additional known allele, Thai-type, was not detected. Phylogenetic analysis based on the MPSP gene sequences, including 3 standard stocks generated in the laboratory (T. sergenti Wenchuan, T. sergenti Ningxian, and T. sergenti Liaoyang), revealed that the isolates of Chinese sergenti were comprised of at least 4 allelic MPSP gene types, i.e., C-, I-, B1-, and B2-type, and these parasites with 6 MPSP types 1–5 and 7 were present in China.

Cucullanus mycteropercae n. sp. is described from the intestine of the black grouper, Mycteroperca bonaci Poey, from the northern coast of Yucatán, México. The new species is readily distinguishable from other Cucullanus species because it possesses an ellipsoidal papilla-like structure situated medially on the anterior cloacal lip of males. Other differentiating characters include the variable position of postcloacal pair 8 in males, the subventral position of phasmids, a slightly ventrally hooked posterior end of gubernaculum, and the presence of a large, cylindroconical sclerotized tail end in both sexes. This is the fourth record of a marine cucullanid off the Yucatán Peninsula in México belonging to Cucullanus Müller, 1777.

Parabrachycoelium longicaecum n. gen., n. sp. (Digenea: Brachycoeliidae) is described from the intestine of a plethodontid salamander Chiropterotriton sp. Hosts were collected in bromeliads at the cloud forest of Tlaquilpa, Veracruz, Mexico. Members of the Brachycoeliidae Looss, 1899 (sensu Yamaguti, 1971) are characterized by having a spined tegument; ceca usually short, not passing level of gonads, but longer in some species; gonads posterior to, or in region of, acetabulum, with ovary anterior to testes; a well developed cirrus pouch containing a bipartite seminal vesicle; and uterus occupying entire hind-body posterior to testes. However, this combination of morphological traits prevents the inclusion of the new taxon in any of the genera in that family; a new genus was, therefore, erected to accommodate the new species. The new taxon is readily distinguished from members belonging to Brachycoelium Dujardin, 1845, Mesocoelium Odhner, 1910, and Tremiorchis Mehra and Negi, 1925, by having long ceca extending into the posterior third of the body, slightly surpassing the testes, and vitellaria extending along the body. The new species morphologically resembles Caudouterina rhyacotritoni Martin, 1966, a digenean parasitizing a plethodontid salamander; however, the latter species lacks spines in the tegument and is actually placed within the Allocreadiidae. To demonstrate further the phylogenetic position of the new taxon, we sequenced the D1–D3 regions of 28S rRNA gene and conducted a phylogenetic analysis of available sequences for the order to which brachycoeliids belong (Plagiorchiida). Sequence divergence of the partial 28S rRNA gene confirms its distinction from the aforementioned brachycoeliids, and the phylogenetic position within the Plagiorchiida places the new species as closely related to a clade formed by Brachycoelium Mesocoelium. Divergence levels and phylogenetic position within the Plagiorchiida verifies the validity of the new genus and its inclusion in Brachycoeliidae.

The aim of the present study was to evaluate the viability of Neospora caninum sporulated oocysts after various chemical and physical treatments. Bioassays in gerbils and molecular techniques (PCR-RFLP) were used for identification of the oocysts shed by experimentally infected dogs. Sporulated oocysts were purified and divided into 11 treatment groups as follows: absolute ethanol for 1 hr; 20 C for 6 hr; 4 C for 6 hr; 60 C for 1 min; 100 C for 1 min; 10% formaldehyde for 1 hr; 10% ammonia for 1 hr; 2% iodine for 1 hr; 10% sodium hypochlorite for 1 hr; 70% ethanol for 1 hr; and one group was left untreated and kept as a positive control. All chemical treatments were performed at room temperature (37 C). A total of 33 gerbils, or 3 gerbils per treatment, were used for bioassays. After treatment, the oocysts were divided into aliquots of 1,000 oocysts and orally administered to gerbils. After 63 days, the gerbils were anesthetized and killed with 0.2 ml of T61; blood and tissue samples were collected for serological (IFAT and western blotting), molecular (real-time PCR), histopathology, and immunohistochemical tests. Treatments were considered effective only if all 5 detection techniques tested negative. High temperatures at 100 C for 1 min and 10% sodium hypochlorite for 1 hr were the only treatments that met this condition, effectively inactivating all oocysts.

Dogs are reservoir hosts for Trypanosoma cruzi, the causative agent of American trypanosomiasis. A rapid immunochromatographic dipstick test (ICT) is available commercially for canine serological testing. The ICT was developed with the use of sera from South American dogs, but it is not routinely used in the United States. We evaluated the utility of the ICT in detecting anti–T. cruzi antibodies in dogs from the United States. Dogs (N  =  64) were experimentally infected with United States' isolates of T. cruzi from an opossum (Didelphis virginiana), an armadillo (Dasypus novemcinctus), and a domestic dog (Canis familiaris), and were tested after experimental infection. Sera from uninfected United States dogs (n  =  79; hemaculture negative) were used as negative controls. In a blind study, sera were tested by the ICT and compared to the indirect immunofluorescent antibody test with the use of Brazil-strain epimastigotes as antigen. The sensitivity of the ICT was 91% and the specificity was 98% in dogs experimentally infected with United States isolates. Our study indicates that the ICT could be a useful screening tool for serological surveillance of canine T. cruzi exposure in the United States.

A seroepidemiological survey was carried out in China during 2009–2010 to determine the extent of circulating antigens (CAg) for Angiostrongylus cantonensis in the Chinese population using the gold immunochromatographic assay, with the objective of elucidating the nationwide prevalence of angiostrongyliasis in China. A total of 1,730 blood samples was collected and assayed from the general adult population (the “general group”), and those involved in aquaculture or processing of snails Achatina fulica and Pomacea canaliculat (the “occupational group”) from 5 provinces (Fujian, Hunan, Guangdong, Guangxi, and Zhejiang) and 1 municipal city (Beijing). The overall seroprevalence for the “occupational group” was 7.4% (40/540), which was significantly higher (P < 0.001) than that of the “general group” (0.8%, 9/1,190). The seroprevalence in males (9.5%) was significantly higher than in females (4.2%) (P < 0.05). These results demonstrate that angiostrongyliasis represents a significant zoonotic disease in China, requiring the strengthening of food safety for control of this food-borne disease.

Pigs may represent a source of Cryptosporidium sp. infection to humans. The objective of this study was to identify the Cryptosporidium species present in pigs from the State of Rio de Janeiro, Brazil, and verify what risks pigs represent in the transmission of human cryptosporidiosis, because there is no such information to date in Brazil. Ninety-one samples of pig feces were collected from 10 piggeries in 2 municipalities located in the north and northwest regions of the State of Rio de Janeiro, Brazil. A nested polymerase chain reaction (PCR) protocol to amplify an 830-bp fragment of the small subunit rDNA (SSU rRNA) gene was followed by sequencing of all positive PCR samples. Two samples (2.2%) were Cryptosporidium sp. positive and were identified as pig genotype type II (PGII). This genotype has been observed in an immunocompetent person, in cattle without pigs nearby, and from a potential human source. Its potential for zoonotic transmission is little known and should be rigorously studied.

An increasing interest in the association of the presence of antibodies to Toxoplasma gondii and the development of schizophrenia in patients has been generated over the last several years. Some antischizophrenia agents have been shown to have activity against T. gondii in cell culture assays and to ameliorate behavioral changes associated with chronic T. gondii infection in rats. In the present study, we examined the effects of commonly used antipsychotic and mood stabilizing agents (haloperidol, clozapine, fluphenazine, trifluoperazine, and thioridazine) for activity against developing tachyzoites of the RH strain of T. gondii in human fibroblast cell cultures. Neither haloperidol nor clozapine had a measurable effect. Fluphenazine had an IC₅₀ of 1.7 µM, thioridazine had an IC₅₀ of 1.2 µM, and trifluoperazine had an IC₅₀ of 3.8 µM. Our study demonstrates that some agents used to treat schizophrenia have the ability to inhibit T. gondii proliferation in cell culture.

Cats are essential in the life cycle of Toxoplasma gondii because they are the only hosts that can excrete the environmentally resistant oocysts in nature. Nothing is known of the prevalence of Toxoplasma gondii in cats from Sri Lanka. Serum samples from 86 cats from Colombo, Sri Lanka, were tested for antibodies to T. gondii using the modified agglutination test; antibodies were found in 26 (30.2%) cats with titers of 1∶25 in 4, 1∶50 in 4, 1∶100 in 3, 1∶400 in 2, 1∶800 in 3, 1∶1,600 in 4, and 1∶3,200 or higher in 6 cats. Seropositivity increased with age and was higher in stray cats versus pet cats. This is the first report of seroprevalence of T. gondii in cats from Sri Lanka.

The present study assessed the prevalence of Toxoplasma gondii infection in feral cat populations in Seoul using enzyme-linked immunosorbent assay (ELISA) and nested polymerase chain reaction (PCR). A total of 456 feral cats from 17 wards in Seoul was surveyed. The overall prevalence of T. gondii infection was 15.8% (69/456) by ELISA and 17.5% (80/456) by PCR; by gender, 17% (44/259) by ELISA and 16.2% (42/259) by PCR in males and 14.3% (28/196) by ELISA and 19.4% (38/196) by PCR in females. On a baseline of the Han River, prevalence was 15.1% (29/192) by ELISA and 15.6% (30/192) by PCR in the upper region and 16.4% (43/264) by ELISA and 18.9% (50/264) by PCR in the lower area. This suggested that toxoplasmosis is widespread throughout Seoul's feral cat population and it is critical that the city institute policies for the control of the feral cat population to reduce the risk of toxoplasmosis transmission to animals, including humans.

The distribution of Schistosoma genotypes among individuals in snail populations provides insights regarding the dynamics of transmission and compatibility between schistosome and snail hosts. A survey of Biomphalaria alexandrina from Damietta (Nile Delta, Egypt), an area subjected to persistent schistosomiasis control efforts, provided only 17 snails infected with Schistosoma mansoni (6.1% overall prevalence), each shown by microsatellite analysis to have a single genotype infection. By contrast, recent studies of uncontrolled S. mansoni transmission foci in Kenya revealed that 4.3% Biomphalaria pfeifferi and 20–25% Biomphalaria sudanica snails had multiple genotype infections. Compared with the 3 Kenyan populations, the Egyptian population of S. mansoni also showed a lesser degree of genetic variability and was genetically differentiated from them. We suggest that tracking of genotype diversity in infected snails could be further developed to serve as an additional and valuable independent indicator of efficacy of schistosomiasis control in Egypt and elsewhere.

The molecular characterization of the daniconematid dracunculoid Mexiconema cichlasomae Moravec, Vidal, and Salgado-Maldonado, 1992 through the sequencing of SSU rDNA from adult individuals is presented herein. Additionally, preliminary genetic relationships of this nematode are inferred from alignment of sequences generated previously for other dracunculoids. Maximum parsimony and maximum likelihood analyses recovered identical trees. As anticipated by previous taxonomic work, M. cichlasomae is putatively closely related to skrjabillanid dracunculoids represented by Molnaria intestinalis (Dogiel and Bychovsky, 1934) and Skrjabillanus scardinii Molnár, 1966 SSU rDNA sequences, but the relationships of this newly discovered clade to other dracunculoid clades remain unresolved.

Nematocysts containing coiled polar filaments are a distinguishing feature of members of the phylum Cnidaria. As a first step to characterizing the molecular structure of polar filaments, a polyclonal antiserum was raised in rabbits against a cyanogen bromide–resistant protein extract of mature cysts containing spores of Myxobolus pendula. The antiserum reacted only with proteins associated with extruded polar filaments. Western blot and whole-mount immunohistochemical analyses indicated a conservation of polar filament epitopes between M. pendula and 2 related cnidarians, i.e., the anthozoan, Nematostella vectensis, and the hydrozoan, Hydra vulgaris. This conservation of polar filament epitopes lends further support to a shared affinity between Myxozoa and cnidarians.

Antibodies to Encephalitozoon cuniculi were examined by enzyme-linked immunosorbent assay using E. cuniculi PTP2 recombinant protein and by Western blot analysis on a total of 472 dog serum samples that had been collected in Japan. Of these samples, 21.8% (103/472) had antibodies against E. cuniculi. Each of 5 serum samples that showed high (>1.0) or low (<0.1) OD value was selected randomly and further examined by Western blot using E. cuniculi–native antigens. All samples with high OD values reacted with specific E. cuniculi proteins, including an antigen of approximately 35 kDa corresponding with PTP2; sera with low OD values did not recognize this E. cuniculi band. This study is the first to demonstrate the prevalence of E. cuniculi infection in dogs in Japan.

Wild-caught snakes are a popular and traditional food in China. However, little known to the public, snakes are also intermediate hosts of Spirometra erinaceieuropaei, a food- and water-borne pathogen of sparganosis. Therefore, we investigated the prevalence of S. erinaceieuropaei in 10 popular species of wild-caught snakes in Guangzhou City (Guangdong Province) between July 2009 and July 2010. One hundred and twenty-four specimens of 10 species (including Enhydris plumbea, Zoacys dhumnades, Elaphe radiate, Elaphe taeniura, Elaphe carinata, Ptyas mucosus, Ptyas korros, Naja naja atra, Bungarus fasciatus, and Bungarus multicinctus) were randomly selected from a total of 1,160 wild-caught snakes. They were obtained from food markets in 5 representative districts (Huadou, Panyu, Tianhe, Haizhu, and Conghua). The specimens were killed, necropsied, and examined for parasitic helminths. Of the snakes examined, 29.8% were infected by spargana and the worm burden per infected snake ranged from 1 to 221. Most species were infected except for En. plumbea, B. fasciatus, and B. multicinctus. Prevalence even reached 100% in Zoacys dhumnades. More than half (53.5%) of the spargana were located in muscular tissue, 36.4% in subcutaneous tissue, and 10.1% in the coelomic cavity. The study revealed the potential risk for the zoonotic sparganosis by eating wild-caught snakes and will be helpful in arousing public health concern about the consumption of snake meat.

A seroepidemiological survey of Neospora caninum infection in dairy cattle was carried out in China's southern Guangdong Province between July 2009 and March 2010. A total of 370 serum samples of dairy cattle was collected from 5 farms and examined for antibodies to N. caninum by enzyme-linked immunosorbent assay. The overall seroprevalence of N. caninum in dairy cattle was 18.9% (70/370). The seroprevalence of N. caninum in aborting cows (22.7%) was higher than that in nonaborting cows (16.3%), but the difference was not statistically significant (P > 0.05). Five-yr-old dairy cattle had the highest seroprevalence (27.8%), followed by those that were 6-yr-old (20.4%). Dairy cattle with 4 pregnancies had the highest seroprevalence (29.2%). There was no apparent association of N. caninum seropositivity with age or number of pregnancies (P > 0.05). The results of the present survey indicated that the infection with N. caninum is prevalent in dairy cattle of all ages in southern China, which may be one of the causes of bovine abortion. This is the first report of seroprevalence of N. caninum in dairy cattle in southern China.