Soil contamination with Toxocara spp. eggs in the public parks of Isfahan City, Central Iran

Soil contamination by Ancylostoma spp. and Toxocara spp. eggs in elementary school playgrounds in the extreme south of Brazil

Millions of people worldwide, and especially schoolchildren, may be infected by geohelminths due to their exposure to a contaminated environment. The aim of this study was to evaluate soil contamination by Ancylostoma spp. and Toxocara spp. eggs in recreation areas at elementary schools in Pelotas, state of Rio Grande do Sul, Brazil. Sand samples were collected from 22 schools and were processed using the centrifugal flotation method. Helminth eggs with zoonotic potential were found in 12 out of the 22 schools (54.5%). Contamination by Ancylostoma spp. and Toxocara spp. was observed in 36.4% (8/22) and 27.3% (6/22) of the soil samples collected at these schools, respectively. These findings of eggs show that the school communities are exposed to risks of zoonotic transmission.

Soil Contamination with Toxocara Eggs in Public Schools in Rural Areas of Southern Thailand

Soil is considered the primary source of Toxocara transmission to humans, especially children. The status of soil contamination with Toxocara eggs in southern Thailand is unknown. This study aimed at estimating the soil contamination with Toxocara eggs in public schools in Nakhon Si Thammarat province in southern Thailand. Soil samples were collected from 12 public schools between August and September 2017. At each site, ten soil samples were collected from the following five types of locations: (1) playgrounds, (2) football fields, (3) sidewalks, (4) schoolyards, and (5) areas around cafeterias. In total, 120 samples were examined for Toxocara eggs with a modified flotation method using a sucrose solution. Toxocara eggs were detected in 8 (66.7%) of the 12 studied public schools. Of the 120 soil samples, 22 (18.3%; 95% CI: 11.9, 26.4) were contaminated with Toxocara eggs. The highest levels of Toxocara egg contamination were observed in playgrounds (41.7%; 95% CI: 22.1, 63.4), followed by football fields (20.8%; 95% CI: 7.1, 42.2), sidewalks (12.5%; 95% CI: 2.7, 32.4), and schoolyards (12.5%; 95% CI: 2.7, 32.4). There were significant differences in the distribution of Toxocara eggs across location types (p < 0.05). The findings demonstrated that the soil samples from public schools were contaminated with Toxocara eggs. Playgrounds were the most heavily contaminated locations. Teaching children proper handwashing steps and discouraging geophagia should be implemented to reduce the distribution of Toxocara and limit future Toxocara infections.

A Systematic Review and Meta-analysis of Toxocariasis in Iran: Is it Time to Take it Seriously?

BACKGROUND

Toxocariasis is one of the neglected zoonosis with considerable public health importance around the world. The current study aimed to elucidate the overall prevalence of Toxocara infection in human and definitive hosts and also the contamination of soil and raw vegetables with the ova of these parasites, in Iran, using systematic review and meta-analysis.

METHODS

Six English and Persian databases were explored from 2000 to 2017 using the terms toxocariasis, Toxocara spp., visceral larva migrans, Iran, epidemiology, and prevalence. This meta-analysis conducted using STATA, and for all statistical tests, a p value less than 0.05 was considered significant. The random-effects model was used to the report of the pooled prevalence with a 95% confidence interval (CI).

RESULTS

The pooled prevalence of toxocariasis in human was calculated as 11% (95% CI 8-13%). In terms of definitive hosts, the pooled prevalence of Toxocara infection in dogs and cats were calculated as 17% (95% CI 14-20%) and 37% (95% CI 26-48%), respectively. Also, the pooled prevalence of Toxocara spp. eggs in the soil and raw vegetable samples were calculated as 18% (95% CI 13-23%) and 2% (95% CI 1-3%), respectively.

CONCLUSIONS

The results of current study demonstrate that toxocariasis should be taken more seriously by health authorities. Implementing an appropriate control program is necessary to reduce the incidence of this disease in Iran.