An evaluation of techniques to diagnose Dioctophyme renale in dogs.

Dioctophyme renale is a nematode with zoonotic potential that affects the kidneys of carnivorous, wild, and domestic mammals. In this study, we sought to evaluate the indirect ELISA method against routine methods used to diagnose dioctophimosis. Hence, 38 dogs parasitized by D. renale, as confirmed by surgery, were selected. The dogs were evaluated by abdominal ultrasound and urinalysis, and their sera were tested by indirect ELISA using D. renale adult secretion and excretion antigen (DES). Five dogs were followed up with serum collections on day 0 (day of surgery) and 30, 60, and 90 days after surgery to evaluate antibody kinetics. Abdominal ultrasound and indirect ELISA successfully diagnosed 37 dogs parasitized by D. renale, while urinalysis diagnosed 29 animals. The positive animals were parasitized with 1-7 parasites; 17 dogs were infected by male and female parasites, 15 only by female parasites, and six were parasitized only by male parasites. When assessing specificity and sensitivity, all techniques showed 100% specificity and 81.6%, 97.4%, and 97.4% sensitivity for urinalysis, ultrasound, and ELISA, respectively (p < 0.001). The five positive dogs that were followed up after surgery showed a progressive decrease in mean absorbances in indirect ELISA (0.644, 0.516, 0.511, and 0.440, respectively). This study demonstrated that the indirect ELISA using the DE antigen could diagnose dioctophimosis regardless of the number, sex, and location of the parasites, with the potential to be used in epidemiological research and implementing immunological and molecular studies, opening new lines of research on D. renale.

Dioctophyme renale é um nematódeo que possui potencial zoonótico e acomete o rim de mamíferos carnívoros, silvestres e domésticos. Neste estudo busca-se avaliar a técnica de ELISA indireto frente metodologias de rotina utilizadas no diagnóstico da dioctofimose. Para isto, 38 cães participaram do estudo, sendo todos parasitados por D. renale, confirmados por cirurgia. Esses cães foram avaliados por ultrassom abdominal, urinálise e seus soros testado por ELISA indireto utilizando antígeno de excreção e secreção (DES) de adultos de D. renale. Destes, cinco cães foram acompanhados com coletas de soro, no dia zero (dia da cirurgia) e após 30, 60 e 90 dias da cirurgia para avaliar a cinética dos anticorpos. O ultrassom abdominal e ELISA indireto apresentaram sucesso no diagnóstico de 37 cães parasitados por D. renale, enquanto que a urinálise diagnosticou 29 animais. Os animais positivos possuíam de um a sete parasitos, 17 cães apresentaram infecções por macho e fêmeas, 15 somente por fêmeas e seis foram parasitados apenas por machos. Na avaliação da especificidade e sensibilidade, todas as técnicas apresentaram 100% de especificidade e 81,6%, 97,4%, 97,4% de sensibilidade para urinálise, ultrassom e ELISA, respectivamente (p < 0,001). Os cinco cães positivos que foram acompanhados após a cirurgia apresentaram diminuição progressiva nas médias de absorbâncias no ELISA indireto (0,644, 0,516, 0,511 e 0,440, respectivamente). O estudo demonstrou que o ELISA indireto utilizando o antígeno DES poderia diagnosticar dioctofimose, independentemente do número, sexo e localização dos parasitos, com potencial para ser utilizada em estudos epidemiológicos e na implementação de estudos imunológicos e moleculares, abrindo novas linhas de pesquisa sobre Dioctophyme renale.

Immunomodulation in the intestinal mucosa of mice supplemented with Lactobacillus rhamnosus (ATCC 7469) and infected with Toxocara canis.

Toxocariasis is an anthropozoonosis caused by the helminth Toxocara canis that shows different clinical manifestations as visceral, ocular, or neurological toxocariasis forms. Probiotics have been studied as alternatives to prevent and treat this parasitosis. Lactobacillus rhamnosus is a prospect that presents immunomodulatory activity that acts to strengthen the intestinal barrier. In this context, the main objective of this study was to evaluate the protective capacity and immunomodulatory action of the probiotic Lactobacillus rhamnosus at the level of the intestinal mucosa in different stages of T. canis infection (acute and chronic). Mice were supplemented by oral gavage with 1 × 107 UFC/mL L. rhamnosus for 15 days before inoculation with 100 embryonated eggs of T. canis. Euthanasia of mice was conducted at three different time points: 2, 15 and 30 days post-inoculation (PI). The brain, lungs and liver were collected to evaluate the intensity of infection. The small intestines were removed, and mucosal cells of the duodenum were collected to perform gene analysis of IFN-γ, IL-10, IL-4 and IL-13 by real-time polymerase chain reaction (qPCR). Jejunum and ileum segments were analysed by histological techniques. A reduction of 51% in infection intensity was observed in the tissue of supplemented animals evaluated 2 days PI; however, analysis of groups 15 and 30 days PI did not show a protective effect. The intestinal mucosa of supplemented animals presented an inflammatory process that initiated at 2 days PI, persisted at 15 days PI and had regressed at 30 days PI. IL-13 transcription was increased in the probiotic group 2 days after supplementation ended; however, the same increase was not observed in the group that was supplemented and infected. Toxocara canis modulated the local immune system, with suppression of IFN-γ at 2 days PI and increased levels of IL-4 and IL-10 at 15 days PI. These results indicate that, under the studied conditions, the protective effect of Lactobacillus rhamnosus against infection caused by T. canis is not related to IL-4, IL-10 or IFN-γ but could be influenced by IL-13 action at 2 days PI. The probiotic stimulated immune cell recruitment to the intestinal mucosa, which can be involved in the diminished capacity of larval penetration in the mucosa, resulting in the reduced infection intensity observed during acute infection.

Antiparasitic treatment using herbs and spices: A review of the literature of the phytotherapy.

This study sought to make a literature review of the medicinal plants Origanum majorana, Origanum vulgare L., Thymus vulgaris L., Cuminum cynimum L., and Rosmarinus officinalis L. with antiparasitic potential. Articles and theses were selected from the LILACS, PubMed, and Google Scholar databases, which comprised the period from 2000 to 2021 (22 years). In all, 49 studies were selected, and the majority were with the plant Origanum vulgare L. (oregano), followed by Thymus vulgaris L. (thyme). Twenty-five genera of parasites were detected, which were described being tested with phytotherapic. The nematode Haemonchus spp. was the most evaluated in these studies, followed by the parasite genera Leishmania, Trichostrongylus, and Toxocara. All plants showed antiparasitic effects, with more or less action, therefore with the potential to continue research in the search for biomolecules to control these parasites.

O presente trabalho faz uma revisão bibliográfica das plantas medicinais Origanum majorana, Origanum vulgare L., Thymus vulgaris L., Cuminum cynimum L. e Rosmarinus officinalis L. com potencial antiparasitário. Foram selecionados artigos e teses nos bancos de dados LILACS, PubMed e Google Acadêmico que compreendiam o período de publicação de 2000 a 2021 (22 anos). Ao todo, foram selecionados 49 estudos, sendo que na maioria constava a planta Origanum vulgare L. (orégano), seguido de Thymus vulgaris L. (tomilho). Foram detectados 25 gêneros de parasitos, os quais foram descritos sendo testados frente a algum fitoterápico. O nematoda Haemonchus spp. foi o mais avaliado nestes estudos, seguido dos gêneros dos parasitos Leishmania, Trichostrongylus e Toxocara. Todas as plantas apresentaram efeitos antiparasitários, com maior ou menos ação, portanto com potencial para dar continuidade aos estudos em buscas de biomoléculas para controle destes parasitos.

Protective effect of the probiotic Lactobacillus acidophilus ATCC 4356 in BALB/c mice infected with Toxocara canis.

Human toxocariasis consists of chronic tissue parasitosis that is difficult to treat and control. This study aimed to evaluate the action of the probiotic Lactobacillus acidophilus ATCC 4356 on larvae of Toxocara canis and the effect of IFN-γ cytokine on parasite-host in vivo (1.109 CFU) and in vitro (1.106, 1.107, 1.108, 1.109 CFU) interactions. Four groups of six BALB/c mice were formed: G1 - L. acidophilus supplementation and T. canis infection; G2 - T. canis infection; G3 - L. acidophilus supplementation; and G4 - PBS administration. Mice were intragastrically suplemented with probiotics for 15 days before inoculation and 48 h after inoculation with 100 T. canis eggs. The inoculation of T. canis was also perfomed intragastrically. The recovery of larvae took place through digestion of liver and lung tissues; the evaluation of IFN-γ gene transcription in leukocytes was performed by qPCR. The in vitro test consisted of incubating the probiotic with T. canis larvae. The supplementation of probiotics produced a reduction of 57.7% (p = 0.025) in the intensity of infection of T. canis larvae in mice, whereas in the in vitro test, there was no larvicidal effect. In addition, a decrease in the IFN-γ gene transcription was observed in both, T. canis-infected and uninfected mice, regardless of whether or not they received supplementation. The probiotic L. acidophilus ATCC 4356 reduced T. canis infection intensity in mice, however, the probiotic did not have a direct effect on larvae, demonstrating the need of interaction with the host for the beneficial effect of the probiotic to occur. Yet, the proinflammatory cytokine IFN-γ did not apparently contributed to the observed beneficial effect of probiotics.

Quantification of Toxocara canis DNA by qPCR in mice inoculated with different infective doses.

The nematode Toxocara canis is of public health importance and is the main causative agent of toxocariasis in humans. This disease is difficult to diagnose due to several factors, including the possibility of cross-reactions with other nematodes in the ELISA. To overcome this problem, molecular tests have been recommended as an alternative to identify the parasite. The quantitative real-time polymerase chain reaction (qPCR) technique was used in this study to identify and quantify the parasite load of T. canis in the mouse brain. To this end, 24 mice were divided into six groups, five of which were challenged with different infective doses of T. canis larvae (L3) (1000, 500, 250, 100 and 50 larvae), while the sixth group, uninfected, acted as negative control. Forty-five days after infection, the animals were euthanized to collect the brain, from which two portions of 20 mg of tissue were taken for DNA extraction, while the rest of the brain tissue was digested to quantify the number of larvae by microscopy. The number of DNA copies was calculated from the standard DNA quantification curve, showing values of E = 93.4%, R2 = 0.9655 and Y = -3.415. A strong positive correlation (R = 0, 81; p < .001) was found between the number of copies and the recovery of larvae from brain. However, the parasite's DNA was also identified even in animals from whose brain no larvae were recovered after tissue digestion. The results of this study therefore confirm that the qPCR technique can be a valuable tool for the detection and quantification of T. canis DNA in murine hosts, even in animals whose with tissues contain very few parasites.

Ovicidal in vitro activity of 2-aryl-3-(2-morpholinoethyl)thiazolidin-4-ones and 2-aryl-3-(3-morpholinopropyl)thiazolidin-4-ones against Fasciola hepatica (Linnaeus, 1758).

Although there is a variety of biological activity reports regarding compounds derived from thiazolidin-4-ones, no data related to ovicidal activity against trematodes, particularly Fasciola hepatica are available. Since there are reports about anthelmintic resistance in F. hepatica, new drugs are required. Thus, this study evaluated ovicidal action in vitro against F. hepatica eggs in two systematic series of thiazolidin-4-ones: 2-aryl-3-(2-morpholinoethyl)thiazolidin-4-ones (1a-h) and 2-aryl-3-(3-morpholinopropyl)thiazolidin-4-ones (2a-h) at different concentrations (20, 2, 0.2, 0.02 and 0.002 µg/ml). The egg hatch assay (EHA) was used to evaluate the ovicidal action property of such compounds. In addition, potential negative effects of the compounds on metabolic activity of bovine kidney (MDBK) cells were evaluated by determining mitochondrial dehydrogenase activity. The eggs used in the EHA were obtained from parasites removed from the liver of cattle, which were discarded by slaugh after sanitary inspection. The results of EHA showed that compounds 2a-h exhibited ovicidal activity, especially compounds 2b which showed 90% ovicidal activity and viability of 93% MDBK cells at the concentration of 2 µg/ml; and 2e with 96-99% ovicidal activity at 0.2 µg/ml, 0.02 µg/ml and 0.002 µg/ml. The results show the potential of compound 2b to continue the studies in the production of new compounds with anthelmintic action.

Detection of Toxocara canis DNA in tissues of experimentally infected mice.

The main etiological agent of toxocariasis is the helminth Toxocara canis. Several difficulties are found in the diagnosis of this disease, because of nonspecific clinical signs and possible cross-reactions that may occur in the available test, the indirect ELISA. Therefore, molecular diagnosis has been indicated as an alternative to conventional diagnosis. The purpose of this study was to evaluate the polymerase chain reaction (PCR) technique for the identification of T. canis in tissues of experimentally infected mice. To this end, nine mice were inoculated with 1500 embryonated eggs and were divided into two groups, the first euthanized 48 h (G1) and the other 30 days post inoculation (G2). Lungs, brain, liver and blood were collected from all the animals for DNA Extraction and tissue digestion, also was collected blood samples for DNA extraction and ELISA test (serum). Toxocara canis DNA was identified in all the inoculated animals using the ITS-2 target gene. The PCR test successfully identified the parasite in the brain, lung and liver of the animals euthanized 48 h PI and 30 days PI. This technique yielded good results in the identification of the parasite in the brain, being more sensitive than the method for the recovery of larvae, in the group with acute infection (48 h PI). The infection was confirmed by PCR within 48 h after infection, while the ELISA indicated serological conversion occurred only 14 days after inoculation. This study demonstrates the ability of PCR to identify T. canis in the liver, lungs and brain during acute and chronic infection.

Seroprevalence of Toxoplasma gondii and Toxocara canis in a human rural population of Southern Rio Grande do Sul.

Due to the growing population of pets, especially homeless dogs and cats, zoonoses still represent a significant public health problem. Toxoplasma gondii and Toxocara spp. are epidemiologically important zoonotic agents as they are etiological factors of human toxoplasmosis and toxocariasis, respectively. These parasites remain neglected even though they are substantially prevalent in rural areas. The aim of this study was to investigate T. gondii and T. canis seroprevalence and risk factors of seropositivity in a rural population in Pelotas municipality, Brazil. The study participants (n=344) were patients of a Basic Healthcare Unit (BHU) located in Cerrito Alegre. Blood samples were collected and tested for T. gondii antibodies by indirect immunofluorescence and T. canis antibodies by an indirect ELISA that targets an excreted-secreted antigen (TES). T. gondii seropositivity was 53.2%, with higher titers (1:256 - 1:1,024) in individuals who habitually eat pork, beef, or chicken, while T. canis seropositivity was 71.8% and concomitant T. gondii and T. canis seropositivity was 38.3%. Among the seropositivity risk factors assessed, only habitual undercooked meat consumption was significant (p = 0.046; OR = 3.7) for T. gondii and none of them were associated with T. canis seropositivity. Both parasites have a high prevalence in rural areas, which reinforces the need to invest in rural community education and health.

Identification of suitable adjuvant for vaccine formulation with the Neospora caninum antigen NcSRS2.

The parasite Neospora caninum is the main cause of abortion in cattle in many countries around the world, so a vaccine is a rational approach method for the control of the disease. An effective vaccine should be able to prevent both, the horizontal and vertical transmission of N. caninum. In this study, the immune vaccinal response of the recombinant protein rNcSRS2 of N. caninum expressed in Pichia pastoris and formulated with water-in-oil emulsion, xanthan gum, and alum hydroxide was assessed in an experimental murine model. Groups of 10 Balb/c mice were subcutaneously inoculated with two doses of prNcSRS2 twenty-one days apart. After the second immunization, four mice from each group were euthanized, and splenocytes were stimulated ex vivo with recombinant protein. The IgG dynamics were evaluated by indirect ELISA, and the splenocytes cytokines transcription by qPCR. All groups elicited specific antibodies against prNcSRS2, with the water-in-oil group showing significantly (p ≤ .05) elevated titers compared to the other groups. The prNcSRS2 protein alone did not induce a significant ex vivo splenic transcription level of IFN-γ, TNF-α, IL-4, IL-10, and IL-12 cytokines, except for IL-17A, and the adjuvant associations with the prNcSRS2 protein induced different cytokine transcription profiles. The water-in-oil emulsion modulated the expression of TNF-α; the xanthan gum modulated IL-4, IL-10, and IL-12; and alum hydroxide modulated IFN-γ, TNF-α, IL-4, IL-10, and IL-12. In conclusion, it was found that the association of the recombinant prNcSRS2 protein with different adjuvants induced different levels of specific antibody, and a distinct splenic cytokine profile in an adjuvant-dependent manner. The mechanisms of adjuvancity activity is complex, so adjuvant formulation may help in the design of efficient vaccine to control Neosporosis.

Lactobacillus rhamnosus reduces parasite load on Toxocara canis experimental infection in mice, but has no effect on the parasite in vitro.

Human toxocariasis is a neglected global parasitic zoonosis. The efficacy of drug treatment for this disease has been hindered by the biological complexity of the main etiological agent, the nematode Toxocara canis. Experimental studies have shown the potential of probiotics to promote a reduction in the parasite load of T. canis larvae. This study aimed to evaluate the effect of probiotic Lactobacillus rhamnosus ATCC 7469 on the parasite load of BALB/c mice with acute toxocariasis and evaluate the direct effect of this probiotic on T. canis larvae in vitro. In vivo administration of probiotics reduced the parasite load of T. canis larvae by 53.3% (p = 0.0018) during the early stage of infection in mice. However, when analyzed in vitro, it was observed that the probiotic did not present a deleterious effect on the larvae, as approximately 90% of these remained viable. These results demonstrate the potential of the probiotic L. rhamnosus in the reduction of T. canis larvae in BALB/c mice and suggest it could be used as an alternative means for the controlling of visceral toxocariasis. However, further studies are required to elucidate the mechanisms of action promoted by this probiotic.

Prevalence of and risk factors for intestinal parasite infections in pediatric patients admitted to public hospitals in Southern Brazil

Abstract INTRODUCTION: This study aimed to evaluate the prevalence of intestinal parasitosis and to identify risk factors associated therewith in hospitalized children. METHODS: Three fecal samples from each patient were evaluated using three different techniques. The patients' nutritional and socioeconomic status and hematologic profiles were evaluated. RESULTS: Of 106 children, 32.1% tested positive for intestinal parasitosis. The associated risk factors were low parental education levels and children's nail-biting habit. Eosinophilia, observed in 15 cases, was not associated with parasitosis. CONCLUSIONS: We recommend routine fecal parasitologic examination for hospitalized children and implementation of educational campaigns on the prevention of these diseases.

Controlling gastrointestinal nematodes in cattle by Bacillus species.

In this study, we tested the in vitro and in vivo larvicidal activity of Bacillus species against gastrointestinal nematodes in cattle, and their viability in the presence of anthelmintics. For in vitro tests, cattle feces naturally infected with trichostrongylides were incubated with spore suspensions of Bacillus circulans (Bcir), B. thuringiensis var. osvaldocruzi (Bto), B. thuringiensis var. israelensis (Bti) or B. thuringiensis var. kurstaki (Btk). Subsequently, residual larvae were counted and identified. All of the Bacillus species showed 60% or more larvicidal effects. Bcir and Bti were selected to be incubated with anthelmintics (moxidectin, nitroxynil and levamisole), and after 24, 72, and 144h, their viability was evaluated. Bti showed highest drug resistance, maintaining a concentration of 1×107CFU/mL. Based on this result, Bti was selected for in vivo tests on calves naturally infected with gastrointestinal nematodes. The calves were dived into four groups: Group 1, Bti suspension of ∼1×109CFU orally administered; Group 2, Bti suspension of ∼1×109CFU orally administered with levamisole (subcutaneously, 150mg); Group 3, only levamisole (subcutaneously, 150mg), and Group 4 untreated. Then 24 and 48h after treatment, larvae numbers were counted. We observed a reduction of 84%, 100%, and 100% after 48h of treatment, respectively, for Groups 1, 2 and 3 treatments in comparison with the untreated. The tested Bacillus species showed larvicidal activity against bovine trichostrongylides, and its association with anthelmintics. It may serve as a promising integrated alternative for control of gastrointestinal nematodes in cattle.

Can Haemonchus placei-primary infected naïve lambs withstand Haemonchus contortus infections?

An experiment was conducted with the objective of evaluating whether a 5000 L3 larvae Haemonchus placei primary infection, a less pathogenic parasite species for sheep, could attenuate highly pathogenic Haemonchus contortus infections in lambs. Thirty nine 6-month-old lambs were divided in three primary-infection groups: (HcPI) H. contortus-primary infected lambs, (HpPI) H. placei-primary infected lambs, and (CTRL) non-infected control lambs. Later, these same individuals, then aged 10-month old, were cross challenged with Haemonchus parasite species, creating four groups: HcPI challenged with H. placei (HcPI-HpCH), HpPI challenged with H. contortus (HpPI-HcCH), HcPI challenged with H. contortus (HcPI-HcCH), and CTRL. After a 60-day challenge period, all animals were necropsied for gastrointestinal worm counts. HcPI faecal egg count average was found to be twice the HpPI FEC group (p<0.0001). The HcPI also showed lower packed cell volume averages compared to the other groups (p<0.0001). Both H. contortus- and H. placei-primary infections displayed immune responses with similar IgG levels. For the challenge trial, the larval doses used were not enough to trigger clinic infection signs in all treated groups, compared to controls, and H. placei primary infection was not able to maintain anti-H. contortus IgG levels in a subsequent H. contortus infection.

Frequency of Toxocara spp. antibodies in umbilical cords of newborns attended atthe University Hospital in Southern Brazil and factors associated with infection.

Toxocariasis is a neglected and geographically widespread parasitic disease. The detection of specific antibodies associated with this disease is required to confirm its clinical diagnosis and to aid in prevention. Although helminth infection during pregnancy can promote foetal immune responses with long-term effects, specific information regarding the risk of Toxocara spp. infection to the human foetus during pregnancy is lacking. Therefore, the present study aimed to investigate the frequency of antibodies against Toxocara spp. in umbilical cord serum samples to determine the neonatal risk factors associated with Toxocara spp. infection. A cross-sectional study of the frequency of specific antibodies against Toxocara spp. was performed on umbilical cord samples of 280 neonates. A cord blood sample was obtained from each newborn after parturition, and serum samples were examined by enzyme-linked immunoassay. Epidemiological data were obtained through a questionnaire regarding obstetric history (abortion history, premature birthhistory, and pregnancy and birth numbers), general aspects (animal contact anddiet) and socio-economic factors. The frequency of anti-Toxocara spp. IgG antibodies in the umbilical cords of neonates was 20% in serum pre-adsorbed with Ascaris spp. antigen. Family income and dog ownership were considered risk factors associated with infection. No association was found between reproductive disorders and Toxocara seropositivity. The 20% frequency rate of anti-Toxocara spp. IgG antibodies in sera from umbilical cords of newborns can be related to IgG binding at the maternal-foetal interface, requiring greater care during pregnancy. Anti-Toxocara IgM and IgE antibodies no were found in umbilical cord serum samples, indicating that no vertical transmission of these parasites occurred in this population. Studies regarding antibodies against Toxocara spp. in umbilical cord sera are important for determining neonatal exposure to these parasites.

Prevalence of and risk factors for intestinal parasite infections in pediatric patients admitted to public hospitals in Southern Brazil.

INTRODUCTION: This study aimed to evaluate the prevalence of intestinal parasitosis and to identify risk factors associated therewith in hospitalized children. METHODS: Three fecal samples from each patient were evaluated using three different techniques. The patients' nutritional and socioeconomic status and hematologic profiles were evaluated. RESULTS: Of 106 children, 32.1% tested positive for intestinal parasitosis. The associated risk factors were low parental education levels and children's nail-biting habit. Eosinophilia, observed in 15 cases, was not associated with parasitosis. CONCLUSIONS: We recommend routine fecal parasitologic examination for hospitalized children and implementation of educational campaigns on the prevention of these diseases.

Human Toxocariasis: Prevalence and Factors Associated with Biosafety in Research Laboratories.

Human toxocariasis is a neglected parasitic disease worldwide. Researchers studying this disease use infectious strains of Toxocara for experiments. Health workers are at risk in the course of their daily routine and must adhere to biosafety standards while carrying out the activities. Researchers on biosafety concerning working with these parasites are insufficient. The aim of this study was to determine the rate of seroprevalence of Toxocara species among health-care research laboratory workers (professors, technicians, and students), and to investigate the risk factors of Toxocara infection associated with laboratory practices. This cross-sectional study involved 74 researchers at two federal universities in southern Brazil from February 2014 to February 2015; 29 researchers manipulated infective strains of Toxocara canis (test group) and 45 did not (control group). Serum samples were examined using enzyme-linked immunosorbent assay. Epidemiological data were obtained via a questionnaire containing information about laboratory routine, eating behavior, and contact with dogs. The seroprevalence of anti-T. canis IgG was 14.9% (11/74; 13.8% [4/29] in the test group and 15.6% [7/45] in the control group). Most individuals in the test group correctly understood the primary mode of infection; however, 13.8% did not use gloves while manipulating T. canis eggs. Knowledge of biosafety must be well understood by health-care professionals doing laboratory work with biological agents. To our knowledge, this is the first study to investigate the rate of seroprevalence of IgG against Toxocara spp. among professionals and students who handle infective forms of the nematode T. canis.

Estudo retrospectivo de sororreatividade para Trypanosoma cruzi em doadores de sangue da região noroeste do Rio Grande do Sul, Brasil / Retrospective study of seroreactivity to Trypanosoma cruzi in blood donors in the northwestern region of Rio Grande do Sul, Brazil

O presente trabalho objetivou investigar os resultados da triagem sorológica para doença de Chagas (DCH) dos doadores do Banco de Sangue do município de Santiago, Rio Grande do Sul, no período de junho de 2001 a maio de 2011. Os dados foram obtidos por meio do Sistema HEMOVIDA®, tendo por base 10.164 bolsas de sangue. Observou-se que 2,7% (272) das doações apresentaram sororreatividade para Trypanosoma cruzi, sendo esta a primeira causa de descarte das bolsas dentre as doenças infecciosas sorologicamente testadas. Entre as bolsas reagentes, 6,3% (17) também apresentaram resultados positivos para outros marcadores sorológicos: hepatite B (9 casos), hepatite C (4 casos), HTLV I/II (3 casos) e sífilis (1 caso). Embora os testes sorológicos confirmatórios e a caracterização da forma clínica sejam etapas relevantes realizadas em centros de referência, os resultados apontam elevado índice de sororreatividade na triagem para T. cruzi nesta área do estudo. Evidenciou-se que a via de transmissão transfusional de T. cruzi pode ocorrer na região noroeste do RS, não sendo permitida, portanto, nenhuma negligência quanto à obrigatoriedade do exame sorológico para DCH nos bancos de sangue

Toxocariasis and childhood asthma: A case-control study.

OBJECTIVE: The objective of this study is to investigate the association between anti-Toxocara IgG seropositivity and asthma in children. METHODS: This was a case-control study conducted in a university hospital in south Brazil between May 2012 and June 2013. Were recruited 208 children up to 12 years old of whom 156 had asthma (cases) and 52 did not have asthma (controls), with a case-control ratio of 3:1 matched by age. Children's parents or guardians were interviewed using a structured questionnaire with closed questions. Serology was performed using enzyme-linked immunosorbent assay (ELISA) with excretory-secretory antigen of Toxocara canis (TES). RESULTS: The seroprevalence of IgG anti-T. canis antibodies was 12.8% in the cases and 7.7% in the controls. There was no significant association between seropositivity to T. canis and risk of asthma (adjusted odds ratio [OR]: 1.89, 95% CI: 0.52 to 6.89, p = 0.33). Household income < 2 minimum salaries, paternal school years < 9, allergic rhinitis in children, a positive family history of asthma and rhinitis and contact with cats were significantly associated with asthma, with adjusted ORs (95% CIs) of 3.05 (1.21 to 7.73), 2.83 (1.11 to 7.18), 10.5 (4.32 to 25.6), 2.65 (1.14 to 6.17), 2.49 (1.07 to 5.78) and 2.73 (1.03 to 7.27), respectively. CONCLUSIONS: This study did not find a statistically significant association between seropositivity to Toxocara sp. and risk of asthma in children. Low family income, low paternal education level, concomitant allergic rhinitis, family history of asthma and allergic rhinitis and contact with cats were independent factors associated with childhood asthma.

Galectins and collectinis expression are increased in Haemonchus contortus-infected corriedale sheep.

Galectins and collectins are proteins classified in the lectin family that have the ability to recognize molecular patterns associated with pathogens. Studies on cattle have demonstrated high expression of these proteins during infection with gastrointestinal nematodes. The aim of this study was to investigate whether the level of Haemonchus contortus infection would alter the expression of galectins (Gal11 and Gal14) and collectins (SPA and CGN) in sheep. Twelve Corriedale sheep exposed to natural infection with nematodes were divided into two groups: group 1 (G1, n = 7) and group 2 (G2, n = 5), with low and high parasite burdens, respectively, based on fecal egg counts and abomasal parasite counts. The fecal egg counts and abomasal parasite counts were significantly different (p < 0.05) between the groups. Galectin and collectin gene expression was observed in all sheep abomasal samples. However, animals with lower infection levels showed lower expression of the genes Gal14, SPA and CGN (p < 0.05). Expression of lectins was associated with the abomasal H. contortus burden, thus suggesting that these proteins may have a role in controlling of this infection.