Sero-epidemiology ofToxocara canisinfection among aboriginal schoolchildren in the mountainous areas of north–eastern Taiwan

Abstract

A sero-epidemiological study of Toxocara canis infection was conducted among Atayal schoolchildren (aged 7-12 years) residing in the mountainous areas of north-eastern Taiwan. The 73 children investigated were each checked for anti-Toxocara IgG, in ELISA based on the larval excretory-secretory antigens of T. canis larvae. A short, self-administered questionnaire was then used to collect relevant information from each subject, including data on the keeping of dogs, playing in soil, eating raw vegetables, and whether the subjects normally washed their hands before eating. Once the seropositive children had been identified, odds ratios (OR), with their corresponding 95% confidence intervals (CI) and P-values, were calculated for each potential risk factor. When diluted 1:64, sera from 42 (57.5%) of the children gave a positive result in the ELISA, indicating that these 42 children were seropositive for T. canis infection. Seropositivity did not appear to be associated with the age or gender of the subject, the eating of raw vegetables, or the regular failure to wash hands prior to a meal. Compared with the other subjects, however, those who admitted living in a household where dogs were kept (OR = 3.79; CI = 1.23-11.69; P = 0.02) or playing in soil (OR = 3.00; CI = 1.10-8.16; P = 0.03) appeared at increased risk of seropositivity.

Human Toxocariasis in Rural Brazilian Amazonia: Seroprevalence, Risk Factors, and Spatial Distribution

“…[32][33][34] Young age, 35 low socioeconomic status, 36 low parental education, 34,37 and poor sanitation 6 are additional factors contributing to Toxocara exposure in some communities. Dog ownership has been identified as a risk factor in several 11,27,35,[37][38][39] although not all 40 studies of urban and rural populations. None of these known risk factors, except for young age, was significantly associated with Toxocara exposure in our population (P values between 0.338 and 0.921 in multivariate models).…”

Toxocariasis: visceral larva migrans in children

“…O fato de possuir cão na casa foi um fator de risco para sorologia positiva em vários estudos 17,19,20,23,24,30,31,[34][35][36] . Alguns autores não encontraram associação entre os donos de cães 17 e a frequência de infecção por Toxocara, o que poderia ser explicado pelas medidas de higiene adequadas adotadas pelos adultos.…”

“…Em outros estudos brasileiros, a idade prevalente foi acima de 5 anos 13,31,33,55 . Em estudos caso-controle, não foi encontrada diferença significativa em relação à idade 17,29,33,[35][36][37]58 .…”

“…Assim como em adultos, essa relação mantém-se até três vezes maior no sexo masculino em relação ao sexo feminino 59 . Entretanto, em vários estudos, não houve diferença estatística entre o sexo masculino e o feminino em pacientes com toxocaríase 16,20,[29][30][31][32][33]35,36,44,55 .…”

Toxocaríase: larva migrans visceral em crianças e adolescentes

“…33 The presence of a dog in the house was a risk factor for seropositivity in several studies. 17,19,20,23,24,30,31,[34][35][36] Some authors have found no association between dog owners 17 and frequency of Toxocara infection, which could be explained by appropriate hygiene measures taken by adults. Other studies have shown an association between positive serology for T. canis in owners of pups under 3 months.…”