Seroprevalence ofToxocaracanisinfection among children in Swaziland, southern Africa

Abstract

As there appeared to be no data available on Toxocara canis infection in the children of Swaziland, a serological survey of T. canis infection was recently conducted among 92 children aged 3-12 years from rural slums in the low- and middle-veld. A child was considered seropositive if, in western blots based on the excretory-secretory antigens of larval T. canis, his or her serum gave a positive result when diluted 1 : 64. Forty-one (44.6%) of the children were found seropositive. There were no statistically significant differences in seroprevalence between the 49 boys and 43 girls investigated (46.9% v. 41.8%) or between the eight subjects aged 12 years and the 47 aged < or = 5 years (62.5% v. 38.3%); the corresponding odds ratios were 0.81 (95% confidence interval=0.36-1.86; P=0.62) and 2.69 (95% confidence interval=0.57-12.62; P=0.20), respectively. The 66 subjects from the middleveld were, however, significantly more likely to be seropositive than the 26 subjects from the lowveld (54.5% v. 19.2%; odds ratio=5.04, with a 95% confidence interval of 1.70-14.98; P<0.01). It seems likely that T. canis infection is common among the children who live in slums in Swaziland, particularly in the country's middleveld, probably as the result of poor hygiene and poor sanitation.

Cerebral Toxocariasis: Silent Progression to Neurodegenerative Disorders?

“…infection is reportedly one of the important childhood zoonotic infections and is more prevalent in African American communities and individuals living in poverty (35). In contrast, higher seroprevalences are reported from developing countries, for example, Nigeria (30%), Brazil (36%), Swaziland (44.6%), Malaysia (58%) Indonesia (63.2%), Nepal (81%), Marshall Islands (86.8%), and La Reunion (93%) (36)(37)(38)(39). However, an accurate analysis of seroprevalences between different countries and studies is hindered by the different methodologies used to detect infections (WB or ELISA), different cutoff titers, and the difficulties in linking infection, titers, and symptomatic disease (19,40).…”

Seroepidemiology of Toxocara Canis infection among primary schoolchildren in the capital area of the Republic of the Marshall Islands

“…Public health nurses collected blood specimen of PSC, after informed consent was obtained from PSC or parents/guardians, from schools located in urban and suburban areas. These well-trained public health nurses interviewed the enrolled schoolchildren by using the structured questionnaire we designed in a previous study [21]. Basic demographic data regarding age, gender, parental occupation, height, weight, self-reported health status, and urbanization levels were collected during the interview.…”

“…Eggs, harvested from the anterior third of the uteri of female worms were cultured according to the method of Fan et al [21,22]. Briefly, the eggs were stirred in 1% (w/v) sodium hypochlorite solution, left for 5 min at room temperature and then centrifuged (5 min at 2000 × g).…”

“…An identical protocol has been used in our previous studies [21,22]. When larvae were required, the embryonated eggs were hatched under aseptic conditions; the eggs were washed with sterile phosphate-buffered saline (PBS), resuspended in sterile 1% (w/v) sodium hypochlorite, and incubated in an atmosphere containing 5% CO 2 , for 30 min at 37°C.…”

“…The same protocol has been used in our previous studies [21,22]. The larval excretory-secretory antigens were used in western blots to test each serum sample for Toxocara -specific IgG.…”