Vertical transmission of Neospora caninum in bovine fetuses from a slaughterhouse in Brazil.

Neospora caninum is considered as one of the main causes of reproductive failure in cattle. Vertical transmission is the main route of infection in the bovine host and plays an important role in maintaining the parasite in the herd. Molecular detection of N. caninum is important to determine the occurrence of the disease and to evaluate the genetic diversity of the parasite. The present study aimed at assessing the vertical transmission of N. caninum using molecular techniques to detect the parasite in tissue samples from bovine fetuses collected in a slaughterhouse in the state of São Paulo, Brazil. Seventy fetuses and 70 blood samples from pregnant cows were collected in a slaughtering line. Fresh samples of heart and brain tissue from fetuses were analyzed using molecular assays. Serum samples from fetuses and cows were subjected to an indirect fluorescent antibody test (IFAT) to detect antibodies against N. caninum. Nested PCR targeting the internal transcriber 1 (ITS1) region of the protozoan organism was used in the molecular testing. From the total of fetuses examined, 71.42% were positive for N. caninum by PCR. A higher number of heart samples (47.1%) were positive for the parasite using this technique. Antibodies against the protozoa were detected in 12.9% of serum samples of cows; 2.8% of fetuses were seropositive for this pathogen. Our results show that vertical transmission of N. caninum occurs in cattle from this region of Brazil, and that the use of different diagnostic techniques contributes to successful diagnosis of congenital transmission of the parasite in cattle.

Socioeconomic factors associated with infection by Toxoplasma gondii and Toxocara canis in children.

The intense contact of children with domestic animals or environments contaminated with faeces of these animals, together with habits related to lack of hygiene, can facilitate infection by zoonoses. The study evaluated the seroprevalence and risk factors associated with toxoplasmosis and toxocariasis in schoolchildren in the city of Jataizinho, Paraná. Of the 412 children aged 4-15 years, 56.8% (234/412) presented antibodies reactive to Toxoplasma gondii, 42.5% (175/412) presented antibodies reactive to Toxocara canis, and 27.4% (113/412) were reactive for the two species. The analysis of risk factors showed that prevalence of toxoplasmosis and toxocariasis was associated with the level of education of the child's mother (less than eight years of schooling), age range (10-15 years) and the presence of cats in the residence. In addition, family income (up to a minimum wage), presence of a dog, the habit of playing in soil/sand and eosinophilia were associated with Toxocara canis infection. There was an association between the two zoonoses (p < .01), indicating the existence of coinfection. The results show high prevalence of these two important zoonoses, alerting to the need of implementing control measures in order to reduce the incidence and risks of sequelae in children.

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.

Diagnosis and isolation of Toxoplasma gondii in horses from Brazilian slaughterhouses

This study aimed to investigate anti-Toxoplasma gondii antibodies and to isolate the parasite from the brains of horses processed at slaughterhouses in Brazil. We collected brain and blood samples from 398 horses of various ages, from six Brazilian states. Serum samples were evaluated by indirect fluorescent antibody test (IFAT cut-off titre 1:64), and brains were submitted to mouse bioassay. Among the 398 horses, positivity for T. gondii was identified in 46 (11.6%) by IFAT and in 14 (3.5%) by mouse bioassay. In 12 of those 14 bioassays, mice were positive only by IFAT (cut-off titre 1:16), T. gondii being isolated in the remaining two. Using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of 18S rDNA to differentiate among T. gondii, Neospora caninum, and Sarcocystis neurona, we found that two of the 14 brains were positive for T. gondii only. For genotyping of the two isolates and the PCR-positive brain, we performed PCR-RFLP based on 13 markers, and SAG2 all samples were Toxoplasma gondii type I. Collectively, IFAT of horse sera and mouse bioassay identified positivity in 60 (15%) of the samples. Our results show that some horses sent to slaughter in Brazil have been exposed toT. gondii.

O objetivo do estudo foi investigar anticorpos anti-Toxoplasma gondii e isolar o parasita do cérebro de equídeos abatidos em matadouros-frigoríficos no Brasil. Colheram-se amostras de 398 cérebros e sangue de equídeos machos e fêmeas de idades variadas, provenientes de seis estados brasileiros. As amostras de soro foram avaliadas pelo teste de imunofluorescência indireta (IFI) para T. gondii (ponto de corte 64), e os fragmentos de cérebros foram submetidos ao bioensaio em camundongos. Por meio da IFI, 46 (11,6%) equídeos foram soropositivos. Pelo bioensaio em camundongos, 14 (3,5%) cérebros de equídeos testados foram positivos. Em doze dos bioensaios, os camundongos foram positivos somente pela IFI (ponto de corte 16) e T. gondii foi isolado nos outros dois bioensaios. A PCR-RFLP com base em 18S rDNA para diferenciar entre T. gondii, Neospora caninum, e Sarcocystis neurona foram feitas em todos os 14 cérebros e dois foram positivos apenas para T. gondii. De dois isolados positivos para T. gondii e do cérebro positivo à PCR em que realizou-se a PCR-RFLP, com base em 13 marcadores e SAG2, a genotipagem mostrou ser o T. gondii tipo I para todas as amostras. A IFI de soros de equídeos e do bioensaio em camundongos identificaram positividade em 60 (15%) amostras testadas. Os resultados mostram que alguns cavalos enviados para abate foram expostos ao T. gondii.