LARVICIDE ACTIVITY OF LACTOBACILLUS SPP. AND SACCHAROMYCES BOULARDII SUPERNATANTS ON TOXOCARA CANIS.

Experimental studies have demonstrated the potential of probiotics to control visceral toxocariasis, which is a tissue parasitosis that is difficult to treat. This study evaluated the in vitro activity of probiotics and their supernatants on Toxocara canis larvae. The probiotics Lactobacillus rhamnosus (ATCC 7469), Lactobacillus paracasei (ATCC 335), Saccharomyces boulardii, Saccharomyces cerevisiae, and Bacillus cereus var. toyoi were tested in the following preparations: probiotic (P) 1 × 102 to 1 × 109 colony-forming units (CFUs), inactivated probiotic (IP) 1 × 102 to 1 × 109 CFUs, supernatant probiotic (SUpP), and inactivated probiotic supernatant (SupIP). The probiotics and their respective supernatants were separately incubated with 100 T. canis larvae per well using microculture plates with RPMI-1640 medium for 48 hr at 37 C and 5% CO2. The evaluation of the in vitro tests was based on the viability of T. canis larvae, through morphologic integrity, positive motility, and the absence of trypan blue stain. Only culture supernatants (SUpP and SUpIP) of Lactobacillus spp. resulted in 100% dead larvae, whereas S. boulardii showed larvicidal activity in T. canis >70%. The rest of the tests did not show larvicide activity. Therefore, it is important to investigate the supernatant effects of Lactobacillus spp. and S. boulardii in vivo on T. canis visceral infections, their mechanisms of action, and major metabolites involved.

Frequency of enteroparasitic infections and serum positivity for Toxocara spp. in children from a public day care center in Southern Brazil / Frequência de enteroparasitos e de soropositividade para Toxocara spp. em crianças de uma creche pública do Sul do Brasil

Abstract 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.

Resumo Introdução As creches desempenham um importante papel social na educação e desenvolvimento inicial das crianças. O objetivo deste estudo foi investigar a frequência de infecções parasitárias intestinais, além de infecção por Toxocara spp. em crianças de uma creche na cidade do Rio Grande, Rio Grande do Sul, Brasil. Métodos: Para o estudo, foram coletadas amostras fecais de 50 crianças de três a seis anos, analisadas pelas técnicas de Ritchie, Faust, Rugai e Kinyoun, sendo aplicado um questionário epidemiológico fechado e estruturado aos pais/responsáveis ​​das crianças. Também foi realizada uma pesquisa sorológica de anticorpos para Toxocara spp. em 41 crianças, pelo ensaio imunoenzimático, associado ao antígeno de excreção e secreção (ES), com soros pré-adsorvidos com antígeno somático de Ascaris lumbricoides. Resultados: A frequência de enteroparasitos foi de 18%, enquanto que 43.9% das crianças foram soropositivas para Toxocara spp.. Baixa renda familiar e baixo nível de alfabetização dos pais/responsáveis ​​foram fatores comuns entre as famílias das crianças parasitadas. A maioria dos pais ou responsáveis das crianças, com diagnóstico positivo para enteroparasitos ou para Toxocara spp., relatou utilizar apenas água para a higienização de verduras e frutas. Conclusões: As altas taxas de soropositividade para Toxocara spp. indicam que as crianças foram expostas a esse parasito, sendo importante minimizar o risco de infecção. Além disso, a positividade de 18% para enteroparasitos e os dados obtidos com as entrevistas realizadas com os pais ou responsáveis demonstram a necessidade da realização de trabalhos com a população estudada que visem a divulgação sobre as parasitoses intestinais, especialmente sobre medidas profiláticas especificas.

Frequency of enteroparasitic infections and serum positivity for Toxocara spp. in children from a public day care center in Southern Brazil.

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.

Frequency of enteroparasitic infections and serum positivity for Toxocara spp. in children from a public day care center in Southern Brazil

Abstract Introduction Day care centers play an important social role in childrens 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 Kinyouns 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.

Resumo Introdução As creches desempenham um importante papel social na educação e desenvolvimento inicial das crianças. O objetivo deste estudo foi investigar a frequência de infecções parasitárias intestinais, além de infecção por Toxocara spp. em crianças de uma creche na cidade do Rio Grande, Rio Grande do Sul, Brasil. Métodos: Para o estudo, foram coletadas amostras fecais de 50 crianças de três a seis anos, analisadas pelas técnicas de Ritchie, Faust, Rugai e Kinyoun, sendo aplicado um questionário epidemiológico fechado e estruturado aos pais/responsáveis das crianças. Também foi realizada uma pesquisa sorológica de anticorpos para Toxocara spp. em 41 crianças, pelo ensaio imunoenzimático, associado ao antígeno de excreção e secreção (ES), com soros pré-adsorvidos com antígeno somático de Ascaris lumbricoides. Resultados: A frequência de enteroparasitos foi de 18%, enquanto que 43.9% das crianças foram soropositivas para Toxocara spp.. Baixa renda familiar e baixo nível de alfabetização dos pais/responsáveis foram fatores comuns entre as famílias das crianças parasitadas. A maioria dos pais ou responsáveis das crianças, com diagnóstico positivo para enteroparasitos ou para Toxocara spp., relatou utilizar apenas água para a higienização de verduras e frutas. Conclusões: As altas taxas de soropositividade para Toxocara spp. indicam que as crianças foram expostas a esse parasito, sendo importante minimizar o risco de infecção. Além disso, a positividade de 18% para enteroparasitos e os dados obtidos com as entrevistas realizadas com os pais ou responsáveis demonstram a necessidade da realização de trabalhos com a população estudada que visem a divulgação sobre as parasitoses intestinais, especialmente sobre medidas profiláticas especificas.