Showing papers in "Journal of Parasitology in 2013"
TL;DR: The seroprevalence observed in the present study indicates a widespread exposure to T. gondii in livestock in southern Spain, and was significantly higher in herds with a low density of animals.
Abstract: Seroprevalences of Toxoplasma gondii antibodies were assessed with the use of a commercial indirect ELISA in 1,501 domestic ruminants in southern Spain. Antibodies against T. gondii were detected in 420 (83.3%) of 504 cattle, 248 (49.3%) of 503 sheep, and 124 (25.1%) of 494 goats. The herd seroprevalence was 100% (72/72), 84.7% (61/72), and 72.2% (52/72) for cattle, sheep, and goats, respectively. Seropositivity was significantly higher in herds with a low density of animals (P < 0.001). Significant differences (P < 0.05) among municipalities were also found. The seroprevalence observed in the present study indicates a widespread exposure to T. gondii in livestock in southern Spain.
70 citations
TL;DR: The findings indicate that the prevalence of T. gondii infection was higher for animals with open access to wildlife and direct contact with environment than for animals that were intensively farmed or from free-range farms.
Abstract: Consumption of undercooked pork products is considered a major risk factor for contracting toxoplasmosis in humans in several countries. In total, 803 pork samples and 606 wild boar meat samples were collected from different regions of Latvia during June 2010 and February 2011 were tested for Toxoplasma gondii antibodies using an in-house ELISA assay. Seroprevalence in wild boar (33.2%, P < 0.05) was significantly higher than in domestic pig (4.2%). The prevalence of T. gondii–specific antibodies was greater in free-ranging domestic pigs (6.2%, P < 0.05) than those that were intensively farmed (0.4%). Animals from free-range farms had 17.6 times higher odds ratio (OR) (95% confidence interval [CI]: 2.4–129.8) for the presence of specific T. gondii antibodies than animals from intensive farms. The OR (95% CI: 1.1–2.7) of feral wild boars for T. gondii–specific antibodies was 1.7 times higher than for farmed wild boars. Our findings indicate that the prevalence of T. gondii infection was higher f...
57 citations
TL;DR: Goats are found to be potential animal reservoirs of human VL in India, and leishmania donovani DNA was detected by PCR in 20 rK39 positive blood samples from goats and 1 sample from a cow.
Abstract: Visceral leishmaniasis (VL) is a disease that has both zoonotic and anthroponotic etiologies. In India, VL is endemic, considered to be anthroponotic, and caused by Leishmania donovani. Anthroponotic diseases are maintained by transmission from human to human and to a lesser extent from human to animals. Serum samples from 1,220 animals from 7 human VL endemic districts of Bihar, India, were tested for antibodies to a recombinant kinetoplast antigen (rK39 antigen) present in amastigotes of visceralizing Leishmania species, i.e., L. donovani complex. Additionally, PCR was used to examine samples positive by rK39 antigen serology. Antibodies to rK39 indicative of VL were detected in 33 of 1,220 animals. Thirty-one of 867 goats (Capra hircus), 1 of 161 cattle (Bos indicus), and 1 of 54 wild rats (Rattus sp.) were positive by rK39 serology. None of 106 chickens (Gallus domesticus), 26 sheep (Ovis aries), 3 water buffaloes (Bubalus bubalus), or 3 dogs (Canis familiaris) was positive by rK39 serology...
55 citations
TL;DR: The seroprevalence of Toxocara canis antibodies in children aged from 1 to 12 yr old was evaluated in Pelotas City, Rio Grande do Sul, Brazil, and western blotting was used to confirm the ELISA-positive results.
Abstract: The seroprevalence of Toxocara canis antibodies in children aged from 1 to 12 yr old was evaluated in Pelotas City, Rio Grande do Sul, Brazil Human toxocariasis or visceral larva migrans (VLM) was diagnosed with the use of an ELISA based on the T canis excretory-secretory (TES) antigens; Western blotting was used to confirm the ELISA-positive results From 427 samples, 506% were positive for the presence of anti-TES antibodies A confirmatory test (Western blot) was carried out on a sample of the ELISA- positive sera (n ¼ 70), and all were positive The Western blots had specific banding pattern characteristics, where the 30-kDa fraction demonstrated the highest reactivity This fraction could be important for the specific diagnosis of toxocariasis
54 citations
TL;DR: Seasonality was a strong determinant in the parasite community structure of Astronotus ocellatus, and may represent a link in food-web transmissions for parasites because it is used both as definitive and intermediate host.
Abstract: Parasite infracommunities were studied in 202 specimens of Astronotus ocellatus collected from a freshwater lake in the State of Amapa, northern Brazil. Relationships between some host attributes (i.e., ontogeny, sex, and body size) and parasite infections were analyzed, but the primary focus was the seasonal variation in the parasite fauna. In total, 6,308,912 parasites belonging to 11 different taxa were found. Protozoa were the most abundant and dominant taxa, but monogeneans, trematode metacercariae, and nematode larvae were also prevalent and abundant. Fish ontogeny had a weak influence on parasite infection rates; juveniles were more parasitized by Dolops nana and Posthodiplostomum sp. The abundances of all parasite species were weakly correlated with host body size (low r2 values), except D. nana, Contracaecum sp., and Posthodiplostomum sp., which exhibited no correlation between abundance and host body size. Prevalence and abundance were different between flood and drainage seasons for a...
53 citations
TL;DR: Findings in the present study point to the potential pathogenic importance of intra-species polyparasitism in giardiasis and to the mechanisms of enhanced pathogenicity of mixed or non-host specific G. duodenalis infections.
Abstract: In view of the interest in genotype-specific pathogenesis in Giardia duodenalis, the aim of the present study was to examine the effects of infection with different, or mixed, G. duodenalis assemblages on the integrity of human intestinal epithelia. To that end, human epithelial cells (HCT-8) were cultured and exposed to different G. duodenalis assemblages (A, B, and E) or a combination of these assemblages. Epithelial disruption and apoptosis were evaluated by fluorescent microscopy and apoptotic oligonucleosome quantification. The results indicate that infection with trophozoites disrupts epithelial tight junctions and induces varying degrees of enterocyte apoptosis, depending on the infecting assemblage. All disruptions were caspase-3 dependent and were more pronounced when caused by a non-host specific assemblage. Furthermore, infections by isolates in combination with isolates from another assemblage enhanced the epithelial disruption and apoptosis. Further studies in vitro and in vivo are ...
50 citations
TL;DR: Improvement of ESP selection, singly or in a combination, and immunization regimen, namely ESP and type-2 cytokine dose and injection site and schedule, could lead to a sterilizing schistosomiasis vaccine in the foreseeable future.
Abstract: Schistosoma mansoni glyceraldehyde 3-phosphate dehydrogenase (SG3PDH), peroxiredoxin (TPX), and other larval excretory–secretory products (ESP) essentially induce T helper (Th) 1 and Th17 immune responses during a non-protective natural infection. Such an immune environment promotes production of nitric oxide and hydrogen peroxide by interferon-γ–activated monocytes and interleukin (IL)-17–mediated recruitment and activation of neutrophils; however, it also likely prevents engagement of eosinophils and basophils in the hunt for developing larvae. We reasoned that polarizing ESP-induced immune responses toward a Th2 phenotype, via the use of cysteine proteases or type-2 cytokines, would lead to almost total parasite elimination. Accordingly, outbred mice were immunized with 10 μg recombinant SG3PDH and 15 μg TPX-derived peptide together with 10 μg papain, or 200 ng thymic stromal lymphopoietin, IL-25, or IL-33 as an adjuvant. Two weeks later, untreated mice, adjuvant controls, and immunized mice ...
48 citations
TL;DR: This is the first T. gondii isolate characterized genetically from a sick cat in the USA and belongs to the ToxoDB PCR-RFLP genotype no. 4, which is grouped into the Type 12 lineage that is dominant in wildlife from North America.
Abstract: Toxoplasma gondii infections are common in humans and other animals, but clinical disease is relatively rare. It is unknown whether the severity of toxoplasmosis in immunocompetent hosts is due to the parasite strain, host variability, or to other factors. Recently, attention has been focused on the genetic variability among T. gondii isolates from apparently healthy and sick hosts. Whether T. gondii genetic makeup plays a part in the pathogenesis of clinical feline toxoplasmosis is uncertain because little is known of genetic typing of strains associated with clinical feline toxoplasmosis. A 6-mo-old domestic male cat was hospitalized because of lethargy, anorexia, fever, and diarrhea. Numerous (6 million in 1 sample) T. gondii oocysts were found in feces of the cat and antibodies to T. gondii (titer 1:800) were found in its serum by the modified agglutination test. The cat was medicated orally with Clindamycin for 10 days; it became asymptomatic after 10 days and was discharged from the hospital. Viable T. gondii (designated TgCatUs9) was isolated from feces (oocysts) by bioassays in mice. Genetic typing using the DNA extracted from the brains of infected mice and 10 PCR-restriction fragment length polymorphism (RFLP) markers revealed Type II allele at the SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, and PK1 loci and Type I at the L358 and Apico loci; therefore, this isolate belongs to the ToxoDB PCR-RFLP genotype no. 4, which is grouped into the Type 12 lineage that is dominant in wildlife from North America. To our knowledge, this is the first T. gondii isolate characterized genetically from a sick cat in the USA.
44 citations
TL;DR: The results suggest that human C. formosanus infections have been masked by other trematode infections, including Opisthorchis viverrini and Haplorchis taichui, in Lao People's Democratic Republic.
Abstract: In Lao People's Democratic Republic (PDR), we detected 7 patients infected with Centrocestus formosanus (1–122 adult specimens) after praziquantel treatment and purgation, together with several other trematode species including Opisthorchis viverrini and Haplorchis taichui. The patients were all men, 23–42 yr-of-age. Three subjects were from Vientiane Municipality and 1 each were from Khammouane, Saravane, Champassak, and Xiengkhouang Province. The patients had frequently eaten raw freshwater fish and were experiencing variable degrees of epigastric pain and indigestion accompanied by occasional diarrhea, although the relationship of these symptoms with C. formosanus infection was unclear. Centrocestus formosanus specimens were ovoid, 0.46 mm (0.41–0.52 mm) long, and 0.18 mm (0.16–0.20 mm) wide (n = 10) and were equipped with 32 circumoral spines on the oral sucker. The uterine eggs were 33.2 μm long (31.8–34.9 μm) and 18.5 μm wide (17.4–19.8 μm) (n = 20). Analysis of the nucleotide sequence of ...
44 citations
TL;DR: The character of the cephalic space seems to be a criterion that could be routinely used for the easy differentiation of these 2 microfilariae in stained blood films.
Abstract: An examination was made of Giemsa-stained microfilariae in thin blood films from (n = 9) dogs naturally or experimentally infected with Dirofilaria immitis or Dirofilaria repens. Morphological measurements (total length, length of cephalic space, anterior end to nerve ring and last body nucleus, and nucleus-free tail tip) were made on 2–6 microfilariae from each dog with the use of digitally captured images and imaging software. The microfilariae of D. repens were significantly greater (P < 0.001) in all measured dimensions except for the length of the cephalic space, which was significantly shorter (P < 0.001) than that of D. immitis. The cephalic space of D. repens was characterized by being short and routinely being terminated by a distinct pair of nuclei that were separate from the remaining somatic nuclei of the microfilaria. The cephalic space of the smaller microfilaria of D. immitis was longer and did not have the distinct nuclei separated from the somatic column nuclei near the anterior...
43 citations
TL;DR: Molecular phylogenetic analysis of new isolates from the Peruvian Amazon strongly support the separation of the non-avian parasites into a separate genus, and proposes that subgeneric classification of Haemocystidium and Simondia be applied to parasites of squamates and chelonians, respectively.
Abstract: Pigmented hemosporidian parasites that do not exhibit erthyrocytic schizogony, and infect birds, chelonians, and squamates, have been classified in various genera over time. These classifications have reflected vertebrate hosts, insect vectors, and variations in morphology and life history observed in representative species. Side-necked turtles (Podocnemis spp.) from the Peruvian Amazon were screened for hemoparasites and 2 species of hemosporid parasites infecting these hosts were observed. Molecular phylogenetic analysis of these new isolates, along with parasites from lizards, a snake, and a variety of Haemoproteus species from birds from both the Haemoproteus and Parahaemoproteus subgenera, strongly support the separation of the non-avian parasites into a separate genus. The name with precedent for this group is Haemocystidium Castellani and Willey 1909, and we propose that subgeneric classification of Haemocystidium and Simondia be applied to parasites of squamates and chelonians, respecti...
TL;DR: The development of early B. besnoiti tissue cysts in a naturally infected Hugenoot bull from South Africa is reported and anasarca in acute besnoitiosis due to protein-losing glomerulopathy is a finding not previously reported in cattle.
Abstract: Besnoitia besnoiti is an apicomplexan that causes serious economic loss in cattle in many countries and the disease is now spreading in Europe. At least 2 phases of bovine besnoitiosis are recognized clinically. An acute febrile phase characterized by anasarca and necrosis of skin is associated with multiplication of tachyzoites in vascular endothelium; this phase is short-lived and rarely diagnosed. Chronic besnoitiosis characterized by dermal lesions is associated with the presence of macroscopic tissue cysts and is easily diagnosed. Here we report the development of early B. besnoiti tissue cysts in a naturally infected Hugenoot bull from South Africa. Tissue cysts were 10–70 μm in diameter, contained 1–12 bradyzoites, and were most numerous in the dermis, testicles, and pampiniform venous plexus. Amylopectin granules in bradyzoites stained red with periodic acid Schiff (PAS) reaction. Bradyzoites varied in size and in the intensity of PAS reaction (some were PAS-negative), some were plump, a...
TL;DR: It is suggested that temperature and precipitation are the primary drivers of the spatial patterns in avian malaria prevalence along the western slope of the Andes.
Abstract: Environmental heterogeneity largely dictates the spatial distributions of parasites and therefore the susceptibility to infection of host populations. We surveyed avian malaria infections in Rufous-collared sparrows (Zonotrichia capensis) across replicated altitudinal and latitudinal transects along the western slope of the Peruvian Andes to assess geographic patterns of prevalence. We found malaria infection prevalence peaked at midelevations along all 3 altitudinal transects (x ≈ 2,733 m), with highest overall prevalence observed in the northern transect. We observed low levels of malarial parasite diversity, with 94% of infected birds carrying a single Haemoproteus (subgenus Parahaemoproteus) strain. The remaining infected birds harbored either a single alternate Haemoproteus or 1 of 2 Plasmodium strains. Our data suggest that temperature and precipitation are the primary drivers of the spatial patterns in avian malaria prevalence along the western slope of the Andes.
TL;DR: This is the first report of isolation of viable T. gondii from any host in Ethiopia, and these isolates were designated TgCatEt1 to Tg catEt27, of high epidemiologic significance.
Abstract: Cats are important in the epidemiology of Toxoplasma gondii because they are the only hosts that excrete environmentally resistant oocysts in feces. In the present study, hearts, serum, and feces from 36 feral cats from Addis Ababa area, Ethiopia, were examined for T. gondii infection. Antibodies to T. gondii were determined with the modified agglutination test (MAT, cutoff 1:25); 33 cats were seropositive. Hearts of all 36 cats were homogenized, digested in pepsin, and bioassayed in mice. Feces were examined for T. gondii oocysts by bioassay in mice. Viable T. gondii was isolated from heart of 26 by bioassay in mice and from 25 seropositive and 1 seronegative cats. Toxoplasma gondii was isolated from feces (oocysts) by bioassay in mice. In total, viable T. gondii was isolated from 27 of the 36 cats, and these isolates were designated TgCatEt1 to TgCatEt27. The high prevalence of T. gondii oocysts in feces of 8 (19.4%) of 36 cats is of high epidemiologic significance. This is the first report o...
TL;DR: This is the first description of sporocysts, cercariae, metacercariaes, and adults stages of a Posthodiplostomum species in Patagonia, including data about its natural intermediate hosts.
Abstract: In Patagonia, populations of the galaxiid fish Galaxias maculatus are parasitized by metacercariae of a species of Posthodiplostomum (Digenea: Diplostomidae). The aim of this work was to describe larval and adult stages of this species in experimental and natural hosts from an Andean Patagonian lake. Specimens of G. maculatus and the pulmonate snail, Anisancylus obliquus, were collected in Patagua Lake. The snails were isolated in individual containers to observe emergence of cercariae, dissected, and examined under a stereoscopic microscope to record sporocysts and cercariae. Fish were examined to obtain metacercariae, and uninfected fish from Gutierrez Lake were exposed to cercariae from A. obliquus to obtain experimental metacercariae. Chicks and mice were infected with metacercariae from naturally infected G. maculatus to obtain experimental adults. Specimens recovered belong to Posthodiplostomum sp. on the basis of morphological features. This is the first description of sporocysts, cercariae, metacercariae, and adults stages of a Posthodiplostomum species in Patagonia, including data about its natural intermediate hosts.
TL;DR: Results showed that mice vaccinated with rTs-Adsp exhibited an average reduction in the muscle larvae burden, and this protein could be an effective vaccine candidate for trichinellosis.
Abstract: Trichinellosis has major economic impacts on animal husbandry and food safety, and the control and elimination of trichinellosis is a major objective of veterinary medicine. A gene encoding serine protease of Trichinella spiralis (Ts-Adsp) was identified by immunoscreening an adult T. spiralis cDNA library. In this study, the recombinant Ts-Adsp protein (rTs-Adsp) was cloned and expressed in a prokaryotic expression system and purified by Ni-affinity chromatography. To determine whether the purified rTs-Adsp is a potential vaccine candidate for the control of T. spiralis infection, we immunized BALB/c mice with this protein in combination with an alum adjuvant and subsequently challenged with T. spiralis larvae. The results showed that mice vaccinated with rTs-Adsp exhibited an average reduction in the muscle larvae burden of 46.5% relative to the control group. Immunization with the rTs-Adsp antigen induced both humoral and cellular immune responses, which manifested as elevated specific anti-rTs-Adsp IgG and IgE antibodies and a mixed Th1-Th2 response, as determined by Th1 (IFN-c and IL-2) and Th2 (IL-4, IL-10, and IL-13) cytokine profiling, with the Th2 predominant. Thus, purified rTs-Adsp is able to limit the invasion of T. spiralis, and this protein could be an effective vaccine candidate for trichinellosis.
TL;DR: More studies are needed to evaluate the impact of this disease and to establish strategies to follow in order to reduce congenital toxoplasmosis in the populations at risk.
Abstract: The objective of this study was to estimate the seroprevalence of anti–Toxoplasma gondii antibodies and DNA of women with spontaneous abortions in 2 hospitals located in Yucatan, Mexico. Between June 2008 and May 2009, blood samples were taken from 100 women with spontaneous abortion attending the Ticul City Communitarian Hospital and the Merida Mother–Kid Hospital. The sera were tested for anti–T. gondii IgG and IgM antibodies. Blood samples (5 ml with anticlotting agent) were also used for polymerase chain reaction (PCR) assay, to detect T. gondii DNA. Forty-two of the 100 samples were negative. Of the positive samples (n = 58), 32 were positive to IgG, 2 to IgM, 5 to IgG and IgM, 6 to IgG and PCR, 1 to IgM and PCR, and 12 to IgG, IgM, and PCR. Accordingly, 55% of the women were seropositive to at least IgG, 20% to at least IgM, and 19% via PCR. Differences between hospitals were significant (P < 0.05) only for IgM. The risk of infection (IgM positive) was 2.85 (odds ratio [OR] 95%, confidence...
TL;DR: Results of this study indicate very low environmental contamination with T. gondii oocysts around Addis Ababa.
Abstract: Prevalence of Toxoplasma gondii in free-range chickens (Gallus domesticus) is a good indicator of the environmental contamination with oocysts because chickens become infected mainly by feeding from ground, feed, or soil contaminated with oocysts. The seroprevalence of T. gondii antibodies in 125 free-range chickens from the Addis Ababa, Ethiopia, was determined. Antibodies to T. gondii were assayed by the modified agglutination test; 48 of 125 (38.4%) chickens were seropositive, with titers of 1:5 in 14, 1:10 in 12, 1:20 in 14, 1: 40 in 3, 1: 80 in 1, 1:160 in 1, 1:320 in 1, and ≥1:640 in 2 chickens. The hearts of 115 chickens were bioassayed for T. gondii infection. Hearts of 72 seronegative (modified agglutination test [MAT] < 1:5) chickens were pooled in 4 groups (20 + 18 + 19 + 15) and fed to 4 T. gondii-free cats; none of these 4 cats shed oocysts in their feces examined 3–21 days after feeding chicken tissues. Hearts of 43 seropositive chickens (MAT ≥ 1:5) were bioassayed individually in...
TL;DR: H. multivolutinus can be readily distinguished from other species of hemoproteids parasitizing columbiform (Columbiformes) birds and can be distinguished from the latter parasite primarily due to the broadly ovoid shape of its young gametocyte and significantly fewer pigment granules in its fully developed gametocytes.
Abstract: Here we describe Haemoproteus (Haemoproteus) multivolutinus n. sp. from a tambourine dove (Turtur timpanistria )o f Uganda and Haemoproteus (Haemoproteus) paramultipigmentatus n. sp. (Haemosporida, Haemoproteidae) from the Socorro common ground dove (Columbina passerina socorroensis) of Socorro Island, Mexico. These parasites are described based on the morphology of their blood stages and segments of the mitochondrial cytochrome b gene that can be used for molecular identification and diagnosis of these species. Gametocytes of H. multivolutinus possess rod-like pigment granules and are evenly packed with volutin, which masks pigment granules and darkly stains both macro- and microgametocytes in the early stages of their development. Based on these 2 characters, H. multivolutinus can be readily distinguished from other species of hemoproteids parasitizing columbiform (Columbiformes) birds. Haemoproteus paramultipigmentatus resembles Haemoproteus multipigmentatus; it can be distinguished from the latter parasite primarily due to the broadly ovoid shape of its young gametocytes and significantly fewer pigment granules in its fully developed gametocytes. We provide illustrations of blood stages of the new species, and phylogenetic analyses identify DNA lineages closely related to these parasites. Cytochrome b lineages of Haemoproteus multivolutinus and H. paramultipigmentatus cluster with hippoboscid-transmitted lineages of hemoproteids; thus these parasites likely belong to the subgenus Haemoproteus .W e emphasize the importance of using cytochrome b sequences in conjunction with thorough microscopic descriptions to facilitate future identification of these and other avian hemosporidian species.
TL;DR: Immunological results related to vaccination prove that protection is at least partially mediated by specific immunity and support the validity of T. crassiceps murine cysticercosis as an effective tool to identify vaccine candidates against some metacestode infections.
Abstract: Herein we present a review of our research dealing with vaccination against experimental and naturally acquired porcine Taenia solium cysticercosis using Taenia crassiceps-derived antigens. Results strongly support that the different versions of S3Pvac vaccine are indeed effective against porcine T. solium cysticercosis. Immunological results related to vaccination prove that protection is at least partially mediated by specific immunity. The data also support the validity of T. crassiceps murine cysticercosis as an effective tool to identify vaccine candidates against some metacestode infections.
TL;DR: There was no correlation found between the Blastocystis sp.
Abstract: Many helminthic and protozoal infections have been implicated in iron deficiency anemia (IDA) but few reports have suggested a link between Blastocystis sp. infection and IDA. Herein, we investigated the frequency and the association of the Blastocystis sp. genotype with IDA. Two-hundred and six stool samples were examined for Blastocystis sp. Samples were obtained from 96 cases with a confirmed diagnosis of IDA and 110 matched non-anemic controls. The prevalence of the parasite was significantly higher in the IDA group (54.2%) when compared to controls (17.3%) and was 34.5% in all study subjects. Thus, a relationship between Blastocystis sp. infection and IDA was confirmed. PCR amplification of isolates from cases with IDA and controls using subtype-specific sequenced-tagged site primers found that subtype 3 was the most common (83.3%), followed by subtype 1 (16.7%), and both had similar prevalence in both groups. Therefore, there was no correlation found between the Blastocystis sp. genotype and the occurrence of IDA.
TL;DR: Comparison of more than 2,400 base-pair-long sequences of nuclear rDNA from I. mugilicolus and I. alachuaensis n.
Abstract: Intromugil alachuaensis n. sp. is described based on specimens collected from the flathead grey mullet (Mugil cephalus) from the Santa Fe River in Florida. The new species is the fourth recognized species in the genus and the second from North America, with the other 2 being confined to South America. Intromugil mugilicolus from Louisiana and Mississippi is redescribed based on the holotype and newly collected material that was not flattened prior to fixation. Two generic features not previously reported are apparent in the new material from I. mugilicolus and I. alachuaensis n. sp.: an armed oral sucker and a series of sacs containing glandular material arranged in symmetrical rows in the hermaphroditic duct. Intromugil alachuaensis differs from I. mugilicolus by having an oral sucker longer than wide, body spines smaller and lanceolate rather than longer and hastate, and smaller vitelline follicles. Intromugil alachuaensis n. sp. differs from Intromugil simonei by having a large elongated phar...
TL;DR: 4 patterns of between-lineage interactions that seem to be common and might prevent mixing lineages during simultaneous sexual process in wildlife are reported and the next steps should be the development of nuclear markers for distinguishing hemosporidian hybrid organisms and the experimental observation of further development of hybrid ookinetes in vectors.
Abstract: Increasingly frequent outbreaks of zoonotic infections call for studies of wildlife parasites to reach a better understanding of the mechanisms of host switch, leading to the evolution of new diseases. However, speciation processes have been insufficiently addressed in experimental parasitology studies, primarily due to difficulties in determining and measuring mate-recognition signals in parasites. We investigated patterns of sexual process and ookinete development in avian Haemoproteus (Parahaemoproteus) spp. (Haemosporida, Haemoproteidae) using in vitro experiments on between-lineage hybridization. Eleven mitochondrial cytochrome b (cyt b) lineages belonging to 9 species of hemoproteid were isolated from naturally infected passerine birds. The parasites were identified to species on the basis of morphology of their gametocytes and polymerase chain reaction amplification of segments of the cyt b gene. Sexual process and ookinete development were initiated in vitro by mixing blood containing m...
TL;DR: Three unrelated lineages of Hepatozoon parasites were identified in Psammophis, each closely related to lineages previously identified from different lizard groups, on which these snakes feed, indicating that diet might be a key element in transmission, at least for HepatoZoon species of saurophagous snakes.
Abstract: The Apicomplexa are intracellular pathogens of animals, with the Coccidia being the largest group. Among these are the hemogregarines, which include some of the most common hemoparasites found in reptiles. Several studies have reported a possible pattern of prey–predator transmission for some of these parasites. Snakes from the Mediterranean region have been found to be parasitized with Hepatozoon spp. similar to those in lacertids and gekkonids, supporting the prey–predator transmission hypothesis. Here we analyzed specimens of the saurophagous genus Psammophis from North Africa, an ecologically different region. Through molecular analysis of tissue samples we detected 3 different apicomplexan parasites: Caryospora, Sarcocystis, and Hepatozoon. Caryospora was detected in a Forskal's sand snake Psammophis schokari from Algeria, constituting the first time these parasites have been detected from a tissue sample through molecular screening. The obtained Sarcocystis phylogeny does not reflect the ...
TL;DR: Host specificity for species of Rhabdias does not provide support for the evolution of progressive specialization over time, and lungworms from anurans were found not to infect salamanders or reptiles, in nature or in the laboratory.
Abstract: Lungworms of the cosmopolitan genus Rhabdias are among the most common parasites of amphibians and squamate reptiles. The present study used experimental infections, field studies, and a molecular phylogeny to determine the host specificity of 6 Rhabdias spp. that infect snakes and anurans from North America. The molecular phylogeny suggests Rhabdias ranae from Nebraska and Mississippi may represent separate, cryptic species. In addition, the phylogeny strongly supports separate clades for anuran and snake lungworms. Field studies and experimental infections indicate that snake lungworms are generalist snake parasites; however, laboratory experiments also suggest that lizards can be infected under some environmental conditions. Lungworms from anurans were found not to infect salamanders or reptiles, in nature or in the laboratory; anuran lungworm species ranged from strict host specificity, e.g., R. ranae from Nebraska, to relative generalist, e.g., Rhabdias joaquinensis from Nebraska. Overall, ...
TL;DR: The sequences of the isolates were segregated according to the bat host genus or species and suggest that co-evolutionary patterns exist between hosts and parasites and further studies in different Brazilian regions and biomes need to be conducted to gain real understanding of the diversity of trypanosomes in bats.
Abstract: In the order Chiroptera, more than 30 trypanosome species belonging to the subgenera Herpetosoma, Schizotrypanum, Megatrypanum, and Trypanozoon have been described. The species Trypanosoma cruzi, Trypanosoma cruzi marinkellei, and Trypanosoma dionisii are the most common in bats and belong to the Schizotrypanum subgenus. Bats from 2 different biomes, Pantanal and Amazonia/Cerrado in the state of Mato Grosso, Brazil, were evaluated according to the presence of trypanosome parasites by means of hemoculture and PCR in primary samples (blood samples). A total of 211 bats from 20 different species were caught and the trypanosome prevalence, evaluated through hemoculture, was 9.0% (19), 15.5% (13), and 4.8% (6) in the municipalities of Confresa (Amazonia/Cerrado biome) and Pocone (Pantanal biome). Among the 123 primary samples obtained from the bats, only 3 (2.4%) were positive. Phylogenetic analysis using trypanosomatid barcoding (V7V8 region of SSU rDNA) identified all the isolates and primary samp...
TL;DR: This study describes for the first time a species of Angiostrongylus in a wild Felidae in Brazil and differs from all congeneric species by having the anterior extremity with accentuated cuticular expansion and by smaller size of spicules.
Abstract: Angiostrongylus felineus n. sp. (Nematoda, Metastrongyloidea), parasitic in Puma (Herpailurus) yagouaroundi (E. Geoffroy, 1803) (Carnivora, Felidae) from the municipality of Juiz de Fora, Minas Gerais state, Brazil, is described and illustrated herein. Angiostrongylus felineus n. sp. differs from all congeneric species by having the anterior extremity with accentuated cuticular expansion and by smaller size of spicules. This study describes for the first time a species of Angiostrongylus in a wild Felidae in Brazil.
TL;DR: A broadening of the altitudinal range and a new host for Plasmodium (Haemamoeba) lutzi in Colombia provides evidence for a broad host range for P. lutZI that include 2 different orders, Gruiformes and Passeriformes, and also altitudinal expansion of its distribution.
Abstract: This study reports a broadening of the altitudinal range and a new host for Plasmodium (Haemamoeba) lutzi in Colombia. The study was conducted in the city of Bogota, located in the Eastern Cordillera of Colombia at 2,560 m asl (meters above sea level) with an average annual temperature of 15 C. In total, 156 specimens of birds belonging to 25 species and 14 families were captured using mist nets. The blood samples were collected through venipuncture and analyzed by light microscopy. Plasmodium (H.) lutzi was only found in 2 individuals of Turdus fuscater (Great Thrush). This parasite has previously been reported in Aramides cajaneus (before: Aramides cajanea) (Grey-Necked Wood Rail), a bird found in the lowlands of Brazil, Venezuela, and Colombia. This finding provides evidence for a broad host range for P. lutzi that include 2 different orders, Gruiformes and Passeriformes, and also altitudinal expansion of its distribution. The blood stages were compared with the parasite's original descriptions, and the sequence of the parasite's mitochondrial genome (mtDNA) confirms that P. lutzi is a sister taxa of Plasmodium relictum, as previously proposed.
TL;DR: The results show a significant decrease in the concentrations of Giardia, Rotavirus and Adenovirus (P < 0.05), and a trend of decreasing Cryptosporidium densities, without statistical significance, in samples collected monthly in 2010 at the Biological Wastewater Treatment Plant of Ribeirão Preto, SP, Brazil.
Abstract: The persistence of Giardia, Cryptosporidium, Rotavirus, and Adenovirus in samples of raw and treated sewage collected monthly in 2010 at the Biological Wastewater Treatment Plant of Ribeirao Preto, SP, Brazil, was analyzed. The USEPA Method 1623 was used to detect and quantify Giardia and Cryptosporidium. An enzyme immunoassay was carried out to test Rotavirus and Adenovirus antigen optical density (Rotascreen® and Adenoscreen®). The results show a significant decrease in the concentrations of Giardia, Rotavirus and Adenovirus (P < 0.05) and a trend of decreasing Cryptosporidium densities, without statistical significance. Giardia concentrations ranged from 120 to 2,200 cysts/L in raw sewage and from 0.45 to 3.5 cysts/L in treated sewage. Cryptosporidium concentration ranged from undetectable to 28.9 oocysts/L in raw sewage and undetectable to 1.05 oocysts/L in treated sewage. Rotavirus presented absorbance values that ranged from 1.17 ± 0.81 in raw sewage to 0.46 ± 0.32 in treated sewage. Aden...
TL;DR: Although the larval nematode presented low host specificity, it exhibited some host preference and the phylogenetic analysis indicated that Eustrongylides species are divided into 3 well-supported clades.
Abstract: The nematodes Eustrongylides spp. collected from different fish species in China were examined for their intra- and interspecific evolutionary variations using the molecular markers mitochondrial cytochrome oxidase c subunit 1 (COI) gene and internal transcribed spacer (ITS) rDNA regions. The phylogenetic analysis indicated that Eustrongylides species are divided into 3 well-supported clades. The ITS divergence between the clades suggested that clades 2 and 3 might represent the same species, whereas clade 1 represent another cryptic species. The host specificity of these nematodes was analyzed according to prevalence data, host range, and phylogenetic information. Clade 1 was found in 4 fish species, i.e., Odontobutis obscurus, Silurus asotus, Culter mongolicus, and Acanthogobius flavimanus, but was predominant in the 2 perciform species, O. obscurus and A. flavimanus. Clade 2 was found in 3 fish species, Monopterus albus, Channa argus, and Channa asiatica, but was predominant in M. albus, reported to feed primarily on oligochaetes, the first intermediate host of Eustrongylides sp. Clade 3 was found in 9 species, but its low prevalence suggests accidental infection in all species. Although the larval nematode presented low host specificity, it exhibited some host preference.