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Introduction: Day care centers play an important social role in children's early education and development. The objective of this study was to investigate the frequency of intestinal parasitic infections and infection with Toxocara spp. in children from a day care center in the city of Rio Grande, Rio Grande do Sul, Brazil. Methods: The study was conducted using fecal samples from 50 children, ages three to six years, using Ritchie, Faust, Rugai, and Kinyoun's techniques. A closed and structured epidemiological questionnaire was used to collect data from the parents/guardians of the children. Serological studies for detection of antibodies to Toxocara spp. by immunoenzymatic assays using Toxocara excretion and secretion antigen (TES) were conducted on sera collected from 41 children. Results: The frequency of enteroparasites was 18%, with 43.9% of the children testing seropositive for Toxocara spp. Low family income and low literacy levels of parents/guardians were common factors between the families of the parasite-positive children. For the children who tested positive for Toxocara spp., most of the parents/guardians reported using only water for sanitizing raw vegetables and fruits. Conclusions: The high seropositivity rates for Toxocara spp. indicate that children were exposed to this parasite, and it is important to reduce the risk of infection. In addition, the seropositivity for enteroparasites and the interviews with the parents/guardians indicate the need to educate the studied population regarding the modes of intestinal parasite transmission and the prophylactic measures needed to prevent their dissemination.

Toxocariasis is a neglected zoonosis that affects children and adults. Recombinant proteins have been widely investigated for diagnosis, achieving high sensitivity and specificity in an overall population; however, little is known about age as a factor in its application. This study aims to investigate the diagnostic potential of Toxocara canis TES-30 and TES-120 recombinant proteins in humans, differentiating between its performance in children and adults. Serum samples collected from children and adults seropositive to Toxocara spp. were tested with indirect ELISA using T. canis TES-30 and TES-120 recombinant proteins produced in Escherichia coli. While rTES-30 sensitivity was not affected by age (81.8% in children and 87% in adults), rTES-120 sensitivity severely decreased in children to only 63.6%, down from 95.7% in adults. Furthermore, the sensitivity of rTES-30 increased to 97.8% after Western blotting confirmation. High specificity (>94%) against other geohelminths was reported for both recombinant proteins. Our study favors the use of rTES-30 with total IgG as the primary antibody in an indirect ELISA assay as a tool for epidemiological human studies., Competing Interests: The authors have declared that no competing interests exist.

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., (Copyright © 2017 Elsevier B.V. All rights reserved.)

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.

Background: Human toxocariasis is a parasitic zoonosis with a worldwide distribution but is underdiagnosed with an underestimated impact on human health. The ingestion of embryonated eggs of Toxocara spp. present on the hands or in contaminated food or water is the main mode of infection. The only record of Toxocara congenital infection in humans occurred in a premature infant. Helminth infections during pregnancy may be associated with reproductive disorders. Studies investigating the occurrence of toxocariasis in pregnancy are scarce, as is research on the possible implications of these parasites in reproductive health. The aim of this study was to determine the seroprevalence of antibodies to Toxocara spp. in pregnant women and to identify risk factors associated with its infection., Methodology/principal Findings: The cross-sectional study of the seropositivity of specific antibodies for Toxocara spp. was performed on 280 pregnant women. Serum samples were examined with enzyme-linked immunoassay. Epidemiological data were obtained through a questionnaire containing information about obstetric history, general life style choices, and the social and economic status of the women. The prevalence of Toxocara spp. IgG in pregnant women was 6.4%. Some of the risk factors associated with the infection were owning dogs (p = 0.003), living in the city centre (p = 0.028), living at the city beach (p = 0.003), and having a family income at or below minimum wage (p < 0.001). There was no association between reproductive disorders and Toxocara seropositivity., Conclusions/significance: The seroprevalence of 6.4% for Toxocara spp. in pregnant women shows that there was exposure to the parasite. The study demonstrates the need for attention for the completion of clinical diagnosis parameters, as well as the expansion of highly specific serological studies in different regions to understand the impact of toxocariasis in pregnancy.

Visceral toxocariasis is a neglected parasitic zoonosis that occurs through the ingestion of embryonated Toxocara spp. eggs. A wide range of animal species can act as paratenic hosts for this ascarid. The main risk factor for humans is the ingestion of the eggs from contaminated soil; however, infection can also occur through the ingestion of contaminated raw or undercooked infected meat from paratenic hosts. The aim of this study was to verify the presence of Toxocara spp.-specific antibodies in sheep and to determine the risk factors associated with the infection of sheep in Rio Grande do Sul (a major sheep-producing and sheep-consuming state) in southern Brazil. Serum samples collected from 1,642 sheep were tested using an IgG enzyme-linked immunosorbent assay based on the excretory-secretory Toxocara canis antigen. Seroprevalence was 29.0% (477/1,642), and every farm included in the study contained at least one seropositive animal. These results indicate that T. canis infection is widely distributed among sheep herds in Rio Grande do Sul and that it represents a potential risk to human health.