Intra- and Inter-Host Assessment of Bartonella Diversity with Focus on Non-Hematophagous Bats and Associated Ectoparasites from Brazil

The relationship among bats, ectoparasites and associated microorganisms is important to investigate how humans can become exposed to zoonotic agents. Even though the diversity of Bartonella spp. in bats and ectoparasites has been previously reported, the occurrence of gltA genotypes within hosts has not been assessed so far. We aimed to investigate the genetic diversity of Bartonella spp. in non-hematophagous bats and associated ectoparasites by assessing cloned gltA Bartonella genotypes in intra- and inter-hosts levels, as well as by using three additional molecular markers. Overall, 13.5% (18/133) bat blood samples, 17.18% bat flies (11/64) and 23.8% (5/21) Macronyssidae mite pools showed to be positive for Bartonella spp. Seventeen positive samples were submitted to gltA-cloning and three clones were sequenced for each sample. We also obtained 11, seven and three sequences for nuoG, rpoB and ftsZ genes, respectively. None were positive for the other target genes. We found at least two genotypes among the three gltA-cloned sequences from each sample, and 13 between all the 51 sequences. Among the nuoG, rpoB and ftsZ sequences we found eight, five and three genotypes, respectively. In the phylogenetic analysis, the sequences were positioned mainly in groups related to Bartonella identified in rodents, bats and bat flies. Herein, we showed the genetic diversity of Bartonella in bat's blood and associated ectoparasites samples at both intra- and inter-host levels.

Hepatozoon caimani in Caiman crocodilus yacare (Crocodylia, Alligatoridae) from North Pantanal, Brazil

Hepatozoon species are the most common intracellular hemoparasite found in reptiles. Hepatozoon caimani, whose vectors are Culex mosquitoes, has been detected in a high prevalence among caimans in Brazil by blood smears examinations. The present work aimed to detect and characterize the Hepatozoon spp. found in 33 caimans (24 free-ranging and 9 captive; 28 males and 5 females) (Caiman crocodilus yacare) sampled at Poconé, North Pantanal, state of Mato Grosso, Brazil, using blood smears examinations and molecular techniques. Hepatozoon spp.-gametocytes were found in 70.8% (17/24) and 88.8% (8/9) of blood smears from free-ranging and captive caimans, respectively. Hepatozoon spp. 18S rRNA DNA was found in 79.2% (19/24) and 88.8% (8/9) of free-ranging and captive caimans, respectively. Comparative analysis of parasitized and non-parasitized erythrocytes showed that all analyzed features were significantly different (P<0.05) for both linear and area dimensions. Phylogenetic analysis based on 18S rRNA sequences grouped the Hepatozoon spp. sequences detected in the present study together with H. caimani, recently detected in caimans in southern Pantanal.

Pathological and molecular characterization of avian malaria in captive Magellanic penguins (Spheniscus magellanicus) in South America

Avian malaria is a mosquito-borne disease that affects multiple avian species and is caused by protozoans of the genus Plasmodium. An avian malaria infection caused by Plasmodium sp. in Magellanic penguins (Spheniscus magellanicus) with high mortality is described in a zoo in Southern Brazil. Clinically, three birds presented signs of inappetence, anorexia, pale mucosa, dyspnea, and opisthotonus, with death in a clinical course of 5-8 h. At the necropsy, all birds exhibited pale mucosa, marked splenomegaly and hepatomegaly, in addition to moderate leptomeningeal blood vessels ingurgitation in the brain. Microscopically, multiple exoerythrocytic meronts were observed in the cytoplasm of endothelial cells in the spleen, liver, heart, lungs, brain, kidneys, and pancreas. The spleen had a multifocal perivascular inflammatory infiltrate of lymphocytes, plasma cells, and macrophages, which also exhibited hemosiderosis and erythrophagocytosis. The liver had a multifocal periportal inflammatory infiltrate of lymphocytes, macrophages, and plasma cells, in addition to marked hemosiderosis in the hepatic sinusoids. Fragments of spleen, liver, brain, skeletal muscle, and lung were tested by the polymerase chain reaction technique for the detection of a fragment of the cytochrome B gene from haemosporidians, which resulted positive for Plasmodium spp. After sequencing, the samples were phylogenetically associated to Plasmodium sp. detected in Turdus albicollis (KU562808) in Brazil and matched to the lineage TURALB01 previously detected in T. albicollis. Avian malaria infections caused by Plasmodium sp. of lineage TURALB01 may occur in S. magellanicus with high mortality, and, thus, it is essential to detect and characterize the agent involved to obtain the differential diagnosis of the condition.

Hepatozoon sp. gamonts as an accidental finding in synovial liquid from an injured maned wolf (Chrysocyon brachyurus) in southeastern Brazil

A free-living, adult male maned wolf (Chrysocyon brachyurus) was referred to the Governador "Laudo Natel" - FCAV/Unesp veterinary hospital after being found with skin lesions and a fracture on the right pelvic limb, which had to be amputated due to compromised integrity. Around 20 days later, bilateral accentuated swollen on humerus-radius-ulna articulation was observed. The synovial liquid was drained and sent to the laboratory for synovial cytology with Rosenfeld staining that revealed predominantly degenerated neutrophils with karyolytic chromatin associated with intracellular inclusions suggestive of Hepatozoon sp. gametocytes. Blood and synovial liquid samples were submitted to molecular analysis, aiming to amplify the Hepatozoon spp. 18S rRNA gene fragment. Despite the positioning of the found Hepatozoon sequence together with Hepatozoon canis previously detected in domestic carnivores, the BLAST analysis showed only 98% identity with H. canis. To the best of the authors' knowledge, this is the first time a Hepatozoon was detected in the synovial liquid by clinical pathology and molecular analyses.

Outcomes of Trypanosoma cruzi and Trypanosoma evansi infections on health of Southern coati (Nasua nasua), crab-eating fox (Cerdocyon thous), and ocelot (Leopardus pardalis) in the Brazilian Pantanal

The occurrence of Trypanosoma spp. in wild carnivore populations has been intensively investigated during the last decades. However, the impact of these parasites on the health of free-living infected animals has been largely neglected. The Pantanal biome is the world’s largest seasonal wetland, harboring a great diversity of species and habitats. This includes 174 species of mammals, of which 20 belong to the order Carnivora. The present study aimed to investigate the effect of Trypanosoma evansi and Trypanosoma cruzi infections and coinfections on the health of the most abundant carnivores in the Pantanal: coati (Nasua nasua), crab-eating fox (Cerdocyon thous), and ocelot (Leopardus pardalis). We captured 39 coatis, 48 crab-eating foxes, and 19 ocelots. Diagnostic tests showed T. cruzi infection in 7 crab-eating foxes and 5 coatis. Additionally, 7 crab-eating foxes, 10 coatis, and 12 ocelots were positive for T. evansi. We observed coinfections in 9 crab-eating foxes, 8 coatis, and 2 ocelots. This is the first report of T. evansi and T. cruzi infection on the health of free-living ocelots and crab-eating foxes. We showed that single T. evansi or T. cruzi infection, as well as coinfection, caused some degree of anemia in all animals, as well as an indirect negative effect on body condition in coatis and crab-eating foxes via anemia indicators and immune investment, respectively. Furthermore, the vigorous immune investment observed in sampled coatis, crab-eating foxes and ocelots infected by T. evansi, T. cruzi and coinfected can be highly harmful to their health. Overall, our results indicate that single and combined infection with T. evansi and T. cruzi represent a severe risk to the health of wild carnivores in the Pantanal region.

Longitudinal dynamics and health impact of Hepatozoon procyonis (Apicomplexa: Hepatozoidae) on naturally infected ring-tailed coatis Nasua nasua (Carnivora: Procyonidae) from Midwestern Brazil

This study aimed to morphologically and molecularly detect Hepatozoon procyonis in ring-tailed coatis' (Nasua nasua) blood and associated ticks from central-western Brazil, Campo Grande, Mato Grosso do Sul state and also evaluate the impact of the protozoa in blood parameters and coati´s health. Samplings were performed in a conservation area Parque Estadual do Prosa (PEP) and in a Brazilian Air Force Private Area namely Vila da Base Aérea (VBA), between March 2018 and April 2019. We collected 165 blood samples, 61 from recaptured coatis. Peripheral blood smears were stained with Romanovsky-type stain for H. procyonis parasitemia assessment. DNA extracted from blood samples and ticks (Amblyomma spp.) were submitted to a nested PCR (nPCR) assay based on the 18S rRNA gene for Hepatozoon spp. Out of 104 individuals sampled, 80 (77%) were positive for H. procyonis in at least one capture. Overall, 67/165 (40.6%) blood smears showed H. procyonis gametocytes (PEP: 41/63 - 65%; VBA: 26/102 - 25.5%). Parasitemia based on 500 assessed leucocytes ranged from 1 (0.2%) to 50 (10%) and 1 (0.2%) to 25 (5%), from animals sampled in PEP and VBA, respectively. Fluctuation on the parasitemia was observed during recaptures. nPCR results showed higher positivity when compared to blood smears, i.e. 112/165 (68%) positive blood samples [PEP: 41/63 (65%), VBA: 26/102 (25.5%)]. In total, 63/248 (25.4%) tick DNA samples were positive at nPCR for Hepatozoon sp., including 32/87 (37%) pools (1 to 10 larvae) of Amblyomma larvae, 21/105 (20%) pools (1 to 5 nymphs) of Amblyomma sculptum nymphs, 9/43 (21%) pools (1 to 5 nymphs) of Amblyomma dubitatumnymphs, and 1/12 (8%) A. sculptum adult female. The partial 18S rRNA sequence from one coati's blood sample and one representative of each positive tick species randomly selected from each area for sequencing (1,000 bp) showed 100% identity with sequences of H. procyonis from GenBank previously detected in coatis. Regarding H. procyonis infection, no statistical differences were obtained when comparing males vs. females (p-value 0.67), immature animals vs. adults (p-value 0.31), rainy vs. dry season (p-value 0.51) and sampling location (p-value 0.42). No noticeable alteration in blood parameters or heath status was observed in parasite animals. H. procyonis circulates in a high prevalence in coatis from central-western Brazil. Parasitemia fluctuates among different coatis' recaptures and apparently the infection has no influence in coatis' hematological and clinical parameters.

Correction: Outcomes of Trypanosoma cruzi and Trypanosoma evansi infections on health of Southern coati (Nasua nasua), crab-eating fox (Cerdocyon thous), and ocelot (Leopardus pardalis) in the Brazilian Pantanal

[This corrects the article DOI: 10.1371/journal.pone.0201357.].

Molecular detection of Hepatozoon spp. in non-hematophagous bats in Brazil

Even though Hepatozoon spp. has been molecularly detected in several wild animals in Brazil, there is no report on the occurrence of Hepatozoon spp. DNA in bats in Brazil. This study aimed at detecting Hepatozoon, in addition to ectoparasites, in non-hematophagous bats sampled in central-western Brazil using blood smears, hematoxylin-eosin (HE)-staining liver/spleen preparations and molecular and phylogenetic techniques. A total of 135 spleen, 127 liver, and 133 blood samples were collected from 135 non-hematophagous bats from 12 different species in two different sites in Campo Grande, Mato Grosso do Sul state, in the Brazilian Cerrado region. Spleen and blood DNA samples were submitted to two conventional PCR protocols for Hepatozoon spp. based on 18S rRNA. No Hepatozoon spp. gamonts or meronts were observed in blood smears and HE-stained-liver preparations, respectively. While none of the spleen samples was positive for Hepatozoon spp. in the PCR assays, 5 (3 %) blood samples contained 18S rRNA Hepatozoon DNA, including 2/37 (5 %) Artibeus lituratus, 2/32 (6 %) A. planirostris, and 1/23 (4 %) Platyrrhinus lineatus. Out of 5 bats positive for Hepatozoon spp., 3 were parasitized by either Macronyssidae/Spinturnicidae mites or Streblidae flies. BLAST analysis showed that the sequences detected in bats had >99 % identity with Hepatozoon sequences detected in amphibians and reptiles from Brazil, including Hepatozoon caimani detected in Caiman crocodilus. The phylogenetic inferences estimated by the Maximum Likelihood and Bayesian methods clustered the Hepatozoon sequences detected in Brazilian bats with those detected in reptiles and amphibians.

Toxoplasma gondii infection in wild boars (Sus scrofa) from the State of São Paulo, Brazil: Serology, molecular characterization, and hunter's perception on toxoplasmosis

The consumption of wild boar meat, common in many countries, became popular in Brazil after the hunting of these animals was authorized in 2013. The meat of these animals is often consumed by hunters and their social groups, and their offal is occasionally used as supplemental food in the diet of hunting dogs. Given the high frequency of foodborne diseases related to wild boar meat consumption in other countries, including toxoplasmosis, knowledge on these diseases is essential for risk assessment and elaboration of education campaigns for the exposed public. Thus, this study aimed diagnosing, isolating, and genotyping Toxoplasma gondii in hunted wild boars. For that, we obtained samples of serum and tissues (brain, tongue, diaphragm, and heart) from 26 wild boar hunted in three areas in São Paulo State, Brazil, based on convenience sampling strategy. The serum samples were submitted to the indirect immunofluorescence reaction test (IFAT) test while the tissue samples (n = 22) were used to perform a bioassay in mice to isolate the parasite. The isolated samples were genetically characterized by PCR-RFLP with SAG1, 5' and 3' SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico markers. Questionnaires were also formulated and applied to wildlife hunters to assess knowledge about toxoplasmosis. The seroprevalence of T. gondii was 76.9% (20/26), with titers ranging from 16 to 1024. Viable parasites accounted for 4.5% (1/22) of the samples. The ToxoDB #6 genotype of TgJava1 alone was detected. Most interviewed hunters, 84.2% (16/19) consume game meat and a few of them (15.7%; 3/19) prefer undercooked meat. Also, 15.7% (3/19) of the hunters reported supplementing their hunting dogs' diet with wild boar meat and/or offal. As antibodies to T. gondii were detected in 76.9% (20/26) of the studied wild boars, we concluded that infection by T. gondii is frequent in wild boars used for human and animal consumption in the studied areas. Although genotype #6 is commonly found in Brazil in domestic animals, wild animals, and humans, causing everything from mild clinical symptoms to death, this study found, for the first time, the detection of this genotype in wild boars. These results also reaffirm the importance of these animals as a possible source of T. gondii infection for humans and domestic animals.

Genetic diversity of emerging hemotropic mycoplasmas in domestic pigs from Brazil

Mycoplasma suis and Mycoplasma parvum bind strongly to erythrocytes and may cause clinical hemoplasmosis in swine, affecting several age groups. Mycoplasma spp. infected animals may be asymptomatic carriers and/or show nonspecific clinical signs. In Brazil, information on genetic diversity associated with porcine hemoplasmas (PH) has not been described yet. Therefore, this study has aimed to detect, quantify and characterize the genetic diversity of PH in finishing pigs from technified farms in the state of Goiás, central-western Brazil. Ethylenediaminetetraacetic acid-blood samples from 450 swine belonging to 30 different farms from Goiás state were collected at the slaughterhouse. Quantitative real-time PCR (qPCR) assays were performed for the molecular detection and quantification of PH 16S rRNA gene fragments. Cloning and sequencing of 16S and 23S rRNA amplicons were performed to evaluate the genetic diversity. Moreover, a questionnaire was applied to each farm manager to obtain epidemiological information about the herd. The results on qPCR showed herd occurrence of 68.89% for PH. Quantification values (starting quantity [SQ]) ranged from 8.43 × 10^-1 to 4.69 × 10⁶ copies/µl, and 52.71% of the samples presented SQ values equal or lower than 1 × 10³ copies/µl. Risk factors were not evaluated once all farms had at least one positive animal. However, Spearman's coefficient test revealed that the occurrence of PH was inversely associated with the number of farrows per week, weaned piglets per week, and weight at slaughter. Phylogenetic analysis based on maximum likelihood and Bayesian methods showed that the 16S rRNA and 23S rRNA gene sequences obtained from five samples formed a single cluster closely related to M. parvum. Genotype analysis using DNASP software confirmed seven and four different 16S and 23S rRNA genotypes among the cloned amplicons, indicating that there are several genotypes of M. parvum circulating in individual pigs and among pig farms in central-western Brazil.

Parasitic fauna of bats from Costa Rica

Bats are important reservoirs and spreaders of pathogens, including those of zoonotic concern. Though Costa Rica hosts one of the highest bat species' diversity, no information is available about their parasites. In order to investigate the occurrence of vector-borne pathogens (VBPs) and gastrointestinal (GI) parasites of chiropterans from this neotropical area, ectoparasites (n = 231) and stools (n = 64) were collected from 113 bats sampled in Santa Cruz (site 1) and Talamanca (site 2). Mites, fleas and ticks were morphologically and molecularly identified, as well as pathogens transmitted by vectors (VBPs, i.e., Borrelia spp., Rickettsia spp., Bartonella spp.) and from feces, such as Giardia spp., Cryptosporidium spp. and Eimeria spp. were molecularly investigated. Overall, 21 bat species belonging to 15 genera and 5 families were identified of which 42.5% were infested by ectoparasites, with a higher percentage of mites (38.9%, i.e., Cameronieta sp. and Mitonyssoides sp.) followed by flies (2.6%, i.e., Joblingia sp.) and tick larvae (1.7%, i.e., Ornithodoros sp.). Rickettsia spp. was identified in one immature tick and phylogenetically clustered with two Rickettsia species of the Spotted Fever Group (i.e., R. massiliae and R. rhipicephali). The frequency of GI parasite infection was 14%, being 3.1% of bats infected by Giardia spp. (un-identified non-duodenalis species), 1.5% by Eimeria spp. and 9.4% by Cryptosporidium spp. (bat and rodent genotypes; one C. parvum-related human genotype). The wide range of ectoparasites collected coupled with the detection of Rickettsia sp., Giardia and Cryptosporidium in bats from Costa Rica highlight the role these mammals may play as spreaders of pathogens and the need to further investigate the pathogenic potential of these parasites.

The Importance of Coordinated Actions in Preventing the Spread of Yellow Fever to Human Populations: The Experience from the 2016-2017 Yellow Fever Outbreak in the Northeastern Region of São Paulo State

Yellow fever (YF) is a zoonotic arthropod-borne disease that is caused by the yellow fever virus (YFV) and characterized by a sylvatic and urban cycle. Its most severe presentation is manifested as a hemorrhagic disease, and it has been responsible for thousands of deaths in the last decades. This study describes the public health approaches taken to control the 2016-2017 YF outbreak in nonhuman primates (NHPs) that took place in the northeastern region of São Paulo state, Brazil. NHPs recovered from the field were necropsied, and YF diagnoses were made at the Laboratory of Molecular Virology, Ribeirão Preto Medical School and the Center of Pathology, Adolfo Lutz Institute of São Paulo. NHP samples were inoculated into Vero cells for YFV isolation. RNA extraction was performed directly from NHP tissues and tested by RT-qPCR. YFV-positive samples were confirmed by sequencing. Based on the rapid RT-qPCR results, surveillance actions were implemented in the entire region. Confirmatory histopathology and immunohistochemistry for YFV were also performed. Among nine NHPs, gross hepatic involvement was observed in six animals, five of which were YFV-RT-qPCR-positive. One YFV was isolated from the serum of an infant NHP. YFV RNA sequences diverged from the virus responsible for the last epizootic that occurred in São Paulo state, but it was similar to the current Brazilian epizootic. Public health actions included dissemination of information on YF transmission, investigation of the probable location of NHP infection, characterization of the environment, and subsequent creation of the blueprint from which prevention and control measures were implemented. The YFV sylvatic cycle occurred in the periurban areas of the northeastern region of São Paulo state, but no human cases were reported during this period, showing that integrated actions between human, animal, and environmental health professionals were critical to restrain the virus to the sylvatic cycle.

A 50-year-old redescription: molecular and morphometric characterization of Hepatozoon carinicauda Pessôa and Cavalheiro, 1969 in the brown-banded water snake Helicops angulatus (Linnaeus, 1758)

The combined use of molecular and microscopic techniques has become an increasingly common and efficient practice for the taxonomic and evolutionary understanding of single-celled parasites such as haemogregarines. Based on this integrative approach, we characterized Hepatozoon found in Helicops angulatus snakes from the Eastern Amazonia, Brazil. The gamonts observed caused cell hypertrophy and were extremely elongated and, in some cases, piriform (mean dimensions: 25.3 ± 1.9 × 8.6 ± 1.3 μm). These morphological features correspond to Hepatozoon carinicauda, described 50 years ago in the snake Helicops carinicaudus in the southeast region of Brazil. Phylogenetic and genetic divergence analyses, performed with the sequence obtained from the amplification of a 590 bp fragment of the 18S rRNA gene, revealed that Hepatozoon in He. angulatus differed from the other lineages retrieved from GenBank, and was clustered singly in both the phylogenetic tree and the haplotype network. The integration of these data allowed the identification of H. carinicauda in a new aquatic host, and increased the knowledge of its geographical distribution. Therefore, the present study included the first redescription of a Hepatozoon species in a snake from the Brazilian Amazon.

Hemogregarines in bufonid anurans from the Brazilian Amazon, with description a new species of Lankesterella (Apicomplexa: Lankesterellidae)

Here we describe, in an unprecedented way for the Brazilian Amazon, one Apicomplexa species infecting an anuran in Pará, Brazil, using an integrative approach that includes taxonomy, providing morphology, morphometrics, and molecular data. Samples were collected between February 2021 and February 2022 in the community of Curupira, municipality of Santarém, and in the industrial area of Marabá, both in Pará state. Specimens of Rhinella marina and Rhinella diptycha were captured by hand during the active search, and blood samples were collected by cardiac puncture. One blood aliquot was used to prepare blood smears for microscopical analysis and another aliquot for further molecular analyses. Of the five R. marina caught, one (20%) presented parasites morphologically compatible with the parasites belonging to the genus Hepatozoon, while of the three R. diptycha caught, one (33.3%) presented parasites morphologically compatible with the parasites belong to the genera Lankesterella and Hemolivia. Based on molecular data of 18S rDNA sequences, the Hepatozoon sequence obtained clustered with other parasite species recovered from Brazilian amphibians. The Lankesterella sp. sequence was placed in a sister clade of Lankesterella species described in birds and close to L. minima, described in amphibians. All attempts to amplify Hemolivia parasite DNA were unsuccessful. We described Lankesterella oliviacatarinae n. sp. and reported infection by Hepatozoon sp. and Hemolivia sp. in bufonids anurans from the Brazilian Amazon. This study increases knowledge of Brazilian anuran hemoparasites and confirms the importance of using an integrative approach for the taxonomy of these parasite groups.

SU-E-T-474: Monte Carlo Phase Space Production to Model Magnetically Scanned Proton Beams for IMPT

PURPOSE

Accurate dose predictions in proton beam therapy using magnetically scanned beams are highly dependent on the accurate modeling of the lateral dose profiles. This study was performed to provide proton phase spaces for Monte Carlo simulations, used to accurately simulate doses at distances up to 12 cm from the central axis of the beam.

METHODS

Measured lateral dose profiles at various depths in water were compared to Monte Carlo simulations of doses for 90 discreet initial proton energies. Phase spaces were produced using a one dimensional energy distribution, and a combination of several two dimensional spatial and directional distributions. Simulations were performed iteratively using variations in the initial phase space distributions to achieve acceptable agreement between measured and simulated lateral dose profiles, i.e. differences in FWHM < 0.5 mm and dose differences less that 0.1% at distances up to 12.5 cm.

RESULTS

90 phase spaces of proton sources for different initial beam energies were created for use in Monte Carlo simulations of scanned proton beam therapy patient plans. At a depth of 2 cm in water, the simulated and measured FWHM of the lateral dose profiles differed in in-plane direction by an average of 0.05 mm, in cross-plane direction by 0.13 mm. All simulated profiles were within 0.1% of the measured doses at distances between 2cm and 12.5 cm from the central beam axis.

CONCLUSIONS

A library of 90 phase space files has been created to accurately simulate magnetically scanned proton beams for IMPT, providing accurate dose distributions up to 12 cm distance from the central beam axis. This project is supported in part by P01CA021239 from the National Cancer Institute. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Cancer Institute or the National Institutes of Health.

Mansonella sp. and associated Wolbachia endosymbionts in ring-tailed coatis (Nasua nasua) in periurban areas from Midwestern Brazil

Coatis (Nasua nasua) are wild carnivorous well adapted to anthropized environments especially important because they act as reservoirs hosts for many arthropod-borne zoonotic pathogens. Information about filarioids from coatis and associated Wolbachia spp. in Brazil is scant. To investigate the diversity of filarial nematodes, blood samples (n = 100 animals) were obtained from two urban areas in midwestern Brazil and analyzed using blood smears and buffy coats and cPCR assays based on the cox1, 12S rRNA, 18S rRNA, hsp70 and myoHC genes for nematodes and 16S rRNA for Wolbachia. When analyzing coati blood smears and buffy coats, 30% and 80% of the samples presented at least one microfilaria, respectively. Twenty-five cox1 sequences were obtained showing 89% nucleotide identity with Mansonella ozzardi. Phylogenetic analyses clustered cox1 sequences herein obtained within the Mansonella spp. clade. Sequences of both myoHC and two hsp70 genes showed 99.8% nucleotide identity with Mansonella sp. and clustered into a clade within Mansonella sp., previously detected in coatis from Brazil. Two blood samples were positive for Wolbachia, with a 99% nucleotide identity with Wolbachia previously found in Mansonella perstans, Mansonella ozzardi and Mansonella atelensis and in ectoparasites of the genus Pseudolynchia, Melophagus and Cimex. The study showed a high prevalence of Mansonella sp. in the coati population examined, suggesting that this animal species play a role as reservoirs of a novel, yet to be described, species within the Onchocercidae family.

Theileria terrestris nov. sp.: A Novel Theileria in Lowland Tapirs (Tapirus terrestris) from Two Different Biomes in Brazil

The low-land tapir (Tapirus terrestris) is the largest wild terrestrial mammal found in Brazil. Although T. terrestris has been already reported as a host of hemoparasites, the occurrence and genetic identity of Piroplasmida agents in this species is still cloudy. Although it is reported that Theileria equi, an endemic equid-infective agent in Brazil, is occurring in lowland tapirs, these reports are probably misconceived diagnoses since they are solely based on small fragments of 18S rRNA that may not achieve accurate topologies on phylogenetic analyses. The present study aimed to detect and investigate the identity of Theileria spp. in tapirs from Pantanal and Cerrado biomes. Blood-DNA samples from tapirs were screened for a partial (~800 bp) 18S rRNA gene fragment from Piroplasmida and 64 (64/122; 52.46% CI: 43.66-61.11%) presented bands of expected size. Samples were submitted to different protocols for molecular characterization, including near-full length 18S rRNA gene (~1500 bp), and the ema-1 gene from T. equi. Eight sequences were obtained for extended fragments (1182-1473 bp) from the 18S rRNA gene. Moreover, three sequences from partial cox-1 and five from partial hsp70 gene were obtained. None of the samples presented amplifications for the ema-1 gene. Phylogenetic and distance analyses from the 18S rRNA sequences obtained demonstrated a clear separation from tapirs' Theileria spp. and T. equi. Phylogenetic analyses of cox-1 and hsp70 sequences obtained herein also showed a unique clade formed by tapir's Theileria spp. Theileria terrestris sp. nov. is positioned apart from all other Theileria species in 18S rRNA, cox-1, and hps70 phylogenetic analyses. This novel proposed species represents a new Piroplasmida clade, yet to be characterized regarding biological features, vectors involved in the transmission cycles, additional vertebrate hosts, and pathogenicity.

An indirect ELISA for the detection of antibodies against Dirofilaria spp. in cats

BACKGROUND

Dirofilaria immitis and D. repens are mosquito-borne filaroids that primarily infect dogs but also cats. Diagnosing feline dirofilariosis is challenging because of the low parasitic burdens and transient or absent microfilaremia. To improve detection of antibodies against Dirofilaria spp. in cats, an indirect enzyme-linked immunosorbent assay (ELISA) using somatic antigens of D. immitis was standardized.

METHODS

Serum samples from cats positive for D. immitis, D. repens, bronchopulmonary metastrongylids and gastrointestinal helminths as well as negative sera were tested to evaluate the sensitivity (Se) and specificity (Sp). Three different antigen concentrations (2, 3 and 4 μg/ml) and two concentrations of horseradish peroxidase (HRP) IgG anti-cat conjugate (1:10,000 and 1:20,000) were used to screen the optimal titration of the test. Once the best conditions were established, Se and Sp were assessed by testing 151 serum samples positive for D. immitis, D. repens and other parasites (i.e. feline lungworms, gastrointestinal helminths) or negative.

RESULTS

The optimized ELISA showed 89% Se and 98% Sp in detecting D. immitis infections, presenting a cross-reactivity with D. repens. A cut-off point of 1.150 was established to classify positive and negative samples.

CONCLUSIONS

The developed ELISA may improve the detection of antibodies against Dirofilaria spp. in cats, also in epidemiological contexts characterized by multiple helminth infections. Future efforts will focus on reducing the cross-reactivity with D. repens, therefore increasing ELISA Sp.