A Study on the Monitoring of Toxocara spp. in Various Children's Play Facilities in the Republic of Korea (2016-2021)

Toxocara spp. is a zoonotic soil-transmitted parasite that infects canids and felids, which causes toxocariasis in humans, migrating to organ systems, including the lungs, the ocular system, and the central nervous system. Since Toxocara spp. is usually transmitted through soil, children tend to be more susceptible to infection. In order to monitor contamination with Toxocara spp. in children's play facilities in the Republic of Korea, we investigated 11,429 samples of soil from daycare centers, kindergartens, elementary schools, and parks across the country from January 2016 to December 2021. Since the Environmental Health Act in the Republic of Korea was enacted in March 2008, there have been sporadic reports of contamination by Toxocara spp. in children's activity zones. In this study, soil from children's play facilities in regions across the Republic of Korea was monitored according to the Korean standardized procedure to use it as basic data for preventive management and public health promotion. The national average positive rate was 0.16% (18/11,429), and Seoul showed a higher rate of 0.63% (2/318) than any other regions while Incheon, Daegu, Ulsan, Kangwon-do, Jeollabuk-do, and Jeollanam-do were negative (p < 0.05). The positive rates were as follows: 0.37% (4/1089) in daycare centers, 0.13% (3/2365) in kindergartens, 0.2% (7/4193) in elementary schools, 0.09% (1/1143) in apartments, and 0.14% (3/2198) in parks. In addition, it was confirmed that 0.2% (1/498) of elementary schools and 1.17% (2/171) of parks were re-contaminated among play facilities managed with the establishment of a regular inspection cycle. Consequently, there is an essential need for continuous monitoring of Toxocara spp. contamination and regular education for preschool and school children in order to prevent soil-borne parasite infections.

One health approach to toxocariasis in quilombola communities of southern Brazil

BACKGROUND

Toxocariasis has been listed among the most neglected parasitic diseases worldwide, with approximately one fifth of the global population exposed, particularly those living under poverty. In Brazil, communities of descendants of enslaved blacks (quilombola) have historically had some of the highest rates of vulnerability and poverty, characterized by lack of health assistance, poor quality of life, and nutritional insecurity.

METHODS

A cross-sectional sampling of quilombola individuals living in four communities of southern Brazil, as well as their dogs and the soil, was carried out from December 2021 to March 2022. Sociodemographic and other information such as water source, alimentary habits, and dog and cat ownership were gathered using a semi-structured questionnaire for assessing toxocariasis risk factors. Human serum samples were tested by ELISA for anti-Toxocara spp. IgG antibody detection was carried out on dog feces and hair, and soil samples were surveyed for presence of Toxocara spp. eggs.

RESULTS

Overall, 172/208 individuals (82.7%, 95% CI = 77.0-87.2) were seropositive, the highest seroprevalence rate to date in Brazil. Male gender (P = 0.029), educational level (P = 0.026), and drinking water source (P = 0.043) were associated with seropositivity by univariate analysis. Final logistic regression revealed increased odds (P = 0.017, OR = 7.6, 95% CI = 1.5-42.7) to have seropositivity in individuals > 50 years old (< 10 years old). As expected, individuals with soil contact were more likely seropositive (P = 0.038, OR = 4.4, 95% CI = 1.1-18.8). Although retrieved in only 5/96 (5.2%) dog feces, Toxocara spp. eggs were found in 18/60 (30.0%) soil samples.

CONCLUSIONS

The high vulnerability and seroprevalence observed in quilombola communities clearly demand a One Health approach for detection, monitoring, and prevention of infection by Toxocara spp. in both human and dog populations.

One health approach to toxocariasis in Brazilian indigenous populations, their dogs, and soil contamination

Introduction

Although socioeconomic vulnerability and lifestyle factors may contribute to the transmission of Toxocara spp., no study has investigated indigenous populations in Brazil using the One Health approach.

Methods

Accordingly, this study assessed anti-Toxocara spp. antibodies in Brazilian indigenous people and healthcare professionals by enzyme-linked immunosorbent assay. Presence of Toxocara spp. eggs (feces and hair) in dogs as definitive hosts and in soil samples of the indigenous communities were also recovered and molecularly investigated.

Results

Overall, 342/463 (73.9%) indigenous individuals and 46/147 (31.3%) non-indigenous healthcare professionals were seropositive for Toxocara spp. In addition, T. canis eggs were retrieved from 9/194 (4.6%) dog fecal samples and 4/204 (2.0%) dog hair samples, mainly from the Paraná State communities (3/42; 7.1%). Soil contamination was observed only in the Paraná State communities (36/90; 40.0%), with the molecular detection of T. canis. River water consumption was also associated with indigenous seropositivity (Odds ratio, 11.4).

Discussion

Indigenous individuals in Paraná State communities were 2.72-fold more likely to be seropositive than those in São Paulo State, likely due to a lack of sanitary infrastructure. In this scenario, a primarily soil-transmitted disease may also have become waterborne, with embryonated eggs probably spread to water supplies by rain. Full-time healthcare professionals in daily contact with indigenous communities were 9.2-fold more likely to be seropositive than professionals who visited sporadically, suggesting exposure to Toxocara spp. during their work and raising health concerns. In addition, the findings herein showed a significantly higher seroprevalence in indigenous people than in healthcare workers (χ2 = 85.5; p < 0.0001), likely due to overtime exposure to Toxocara spp. In conclusion, Brazilian indigenous communities are highly exposed to toxocariasis, with poor infrastructure and contact with contaminated river water as associated risk factors and a higher risk of infection in healthcare professionals working full-time in these communities.

Testing of sand from recreational areas and sandpits in Warsaw, for presence of Ascaris Lumbricoides and Toxocara spp

INTRODUCTION

Improper maintenance of the cleanliness of sand in sandboxes can be a source of human pathogenic helminths, including Toxocara spp., Enterobius vermicularis, Ascaris lumbricoides, leading to parasitic infections.

AIM OF THE STUDY

The purpose of this study was to evaluate the sanitary condition of sandboxes in playgrounds and recreational areas in Warsaw for the presence of Human roundworm (Ascaris lumbricoides) and Toxocara spp. in sand.

MATERIAL AND METHODS

450 sand samples from 90 sandboxes in the city of Warsaw were analyzed. The flotation method was used for the study, and the material was evaluated using a light microscope. RESULTS. The conducted examinations did not reveal the presence of parasite eggs, indicating that hygiene rules were observed and appropriate recommendations were followed.

CONCLUSIONS

The analyzed sand samples are free of the tested parasites.

A Survey of Intestinal Helminths of Dogs in Slovakia with an Emphasis on Zoonotic Species

Simple Summary

Dogs are the most popular pet animals worldwide; however, frequent and close contact with people increases the risk of transmission of different zoonotic parasites. As the occurrence of intestinal parasites in the dog population is affected by several factors, understanding the epidemiology of zoonotic parasitic infections is important to minimize the risks for humans. This study presents results about the prevalence of gastrointestinal helminths in seven different groups of dogs (pet, shelter, guard, working, and hunting dogs, as well as dogs from segregated Roma settlements) in Slovakia. Out of 495 faecal samples collected between 2016 and 2021, eggs of intestinal helminths were detected in 134 (27.1%) samples. Altogether, six different species/genera/families, namely, Toxocara canis (14.7%), Toxascaris leonina (1.6%), Trichuris vulpis (6.3%), Capillaria spp. (1.4%), Ancylostoma/Uncinaria spp. (8.3%), and taeniid eggs (4.0%), were recorded. Infection with Echinococcus multilocularis was confirmed in 2.2% of dogs and 0.4% of the animals were infested with Taenia hydatigena. The results showed that the occurrence of intestinal helminths is quite frequent in the majority of analyzed dog groups, with a close correlation between the occurrence of intestinal helminths and availability of veterinary care and anthelmintic therapy.

Abstract

Dogs are the most popular pets worldwide; however, close contact with people increases the risk of transmission of different zoonotic parasites. This study aims to determine the prevalence of gastrointestinal helminths in dogs in Slovakia. A total of 495 faecal samples collected from pet, shelter, guard, working (police), and hunting dogs, as well as dogs from segregated Roma settlements between 2016 and 2021, were examined using flotation and molecular methods. Eggs of intestinal helminths were detected in 134 (27.1%) samples. Microscopically, six different species/genera/families, namely, Toxocara canis (14.7%), Toxascaris leonina (1.6%), Trichuris vulpis (6.3%), Capillaria spp. (1.4%), Ancylostoma/Uncinaria spp. (8.3%), and taeniid eggs (4.0%), were recorded. Molecular analyses revealed infection with Echinococcus multilocularis in 2.2% of dogs and 0.4% of the animals were infected with Taenia hydatigena. The results showed a correlation between the occurrence of intestinal helminths and the availability of veterinary care, as dogs from Roma settlements and shelter dogs were the most often infected (66.7% and 39.2%, respectively). On the other hand, working animals were in the best health condition, with only 2.5% being positive. The relatively frequent occurrence of zoonotic species points to the constant need for preventive measures and regular deworming of dogs.

Measurement of the IgG Avidity Index in the Diagnosis of Clinical Toxocariasis Patients

Toxocara spp. are parasitic nematodes responsible for human toxocariasis, a common zoonotic helminth infection. The five main features of human toxocariasis are the classical ocular toxocariasis and visceral larva migrans syndrome, followed by covert toxocariasis, common toxocariasis and neurotoxocariasis. The diagnosis of toxocariasis is feasible by considering clinical symptoms, anamnestic history and serology laboratory results; however, serological criteria cannot be used to distinguish active Toxocara infection from past exposure, which is an area of much discussion in clinical practice. In this context, we developed avidity tests (ELISA and immunoblotting) and evaluated their clinical usefulness in distinguishing past from active toxocariasis. Our study involved 46 patients divided into two groups: “active toxocariasis” (n = 14) and “chronic toxocariasis” (n = 32). According to the avidity indices obtained for both the chronic and active toxocariasis groups, we proposed two thresholds: first, an AI lower than 32% supports an active infection; secondly, a threshold above 42% can exclude an active infection. In order to use this assay in routine clinical practice, however, is still requires standardisation with regards to the method and threshold values, which can be established through studies involving larger populations.

Comparison of the Detection of Toxocara Spp. in the Soils of Public Parks of Ahvaz (Southwest of Iran) by PCR and Loop-Mediated Isothermal Amplification (LAMP)

INTRODUCTION

The infections caused by Toxocara spp. are considered as one of the most important zoonotic diseases in the world, especially in developing countries. Human toxocariasis, particularly in children, is acquired by playing in public parks. Hence, the aim of the current study was to detect Toxocara spp. in the soils of public parks of the city of Ahvaz, southwest of Iran, using the PCR and loop-mediated isothermal amplification (LAMP) methods.

METHODS

In this descriptive cross-sectional study, 260 soil samples were randomly collected from the different public parks of the city of Ahvaz. After performing zinc sulfate (ZnSO₄) flotation technique, the DNA samples were extracted from the isolated Toxocara spp. eggs. Lastly, the extracted DNA was used for PCR and LAMP-based molecular detection.

RESULTS

Out of 260 specimens, 57 (21.9%) samples were found positive for Toxocara spp., using the PCR method, out of that 38 (14.6%) samples were positive for T. canis and 19 (7.3%) samples were positive for T. cati. Also, out of 260 specimens, 81 (31.1%) cases were positive for Toxocara species, using the LAMP method, among them 51 (19.6%) samples were found positive for T. canis and 30 (11.5%) samples were positive for T. cati. Kappa (κ) coefficient between PCR and LAMP showed a strong agreement (0.766, P-value=0.002).

CONCLUSION

The obtained data showed a relatively high outbreak of Toxocara spp. in the public parks' soils of the city, using the PCR and LAMP methods. Since the parasite can cause human toxocariasis, particularly in children; thus, the health authorities of the city of Ahvaz and other similar cities, especially in developing countries, must pay more attention to the hygiene of the public parks' soils.

A prospective seroepidemiological study of toxocariasis during early childhood in coastal Ecuador: potential for congenital transmission and risk factors for infection

Background

Although Toxocara spp. infection has a worldwide distribution, to our knowledge, no data from birth cohorts have been reported in published studies on the potential for congenital transmission and determinants of infection in early childhood.

Methods

We followed 290 mother-infant pairs from birth to 5 years of age through periodic collection of data and samples at birth, 7 and 13 months and 2, 3 and 5 years of age. Data on potential risk factors and confounders were collected by maternal questionnaire. Blood for plasma was collected from the mother at time of birth and periodically from the child for detection of anti-Toxocara spp. immunoglobulin G (IgG) antibodies using a Toxocara canis larval excretory-secretory antigen-based enzyme-linked immunosorbent assay. Stool samples were collected from the mother around the time of birth and periodically from the child for microscopic detection of soil-transmitted helminths (STH). Associations between potential risk factors and Toxocara spp. seroprevalence and seroconversion were estimated using multivariable logistic regression and generalized estimating equations.

Results

Toxocara spp. seroprevalence was 80.7% in mothers and in children was 0%, 9.3%, 48.4%, 64.9%, and 80.9% at 7 months, 13 months, 2, 3 and 5 years, respectively. Risk factors significantly associated with increases in seroprevalence over the first 5 years of life in multivariable analyses were age [Odds ratio (OR) 2.06, 95% confidence interval (CI) 1.39–2.27, P < 0001], male sex (female vs. male: OR 0.66, 95% CI 0.48–0.89, P = 0.006), maternal ethnicity (non-Afro vs. Afro-Ecuadorian: OR 0.65, 95% CI 0.47–0.91, P = 0.011), lower maternal educational and socioeconomic level, and childhood STH (OR 2.29, 95% CI 1.51–3.47, P < 0.001). Seroconversion rates for infection were greatest at 2 years of age (3.8%/month). Factors associated significantly with seroconversion at 2, 3 or 5 years were childhood STH infection, male sex, and more frequent domestic cat exposure.

Conclusions

Our data, from an area of high Toxocara spp. endemicity, indicate no congenital transmission but high rates of seroconversion after 13 months of age reaching maternal levels of seroprevalence by 5 years of age. Factors associated with seroprevalence and seroconversion included STH infections, domestic cats, maternal ethnicity, male sex, STH infections, and markers of greater poverty.

Seroprevalence of Tissue and Luminal Helminths among Patients in Hanoi Medical University Hospital, Vietnam, 2018

A serological survey was performed using ELISA to estimate the prevalence of tissue and luminal helminthic infections among hospital patients in Hanoi region, Vietnam. An overall seroprevalence of tissue and luminal helminthiases was 64.0% (95% CI 61.2–66.8) among 1,120 patients who visited Hanoi Medical University Hospital, Vietnam in 2018. The highest seroprevalence was observed against Toxocara spp. (59.0%), followed by Strongyloides stercoralis (46.3%), Gnathostoma spp. (25.5%), cysticercus (12.8%), Angiostrongylus cantonensis (10.5%), Fasciola spp. (11.1%), and Clonorchis sinensis (8.7%). Mono-infection by one species (11.1%) was lower than multiple infections (53.0%) (P<0.05). The seroprevalence in males (59.3%) was lower than in females (66.2%) but not statistically significant (P>0.05). Children (<15 years) revealed lower seroprevalence (34.0%) than adults (68.4%), and the age group 51–70 years revealed the highest seroprevalence (76.0%). Among the seropositive patients, eosinophilia (≥8.0%) was noted in 80.2%. The present results suggested active transmission of various tissue and luminal helminths among people in Hanoi, Vietnam.

A Sensitive, One-Way Sequential Sieving Method to Isolate Helminths' Eggs and Protozoal Oocysts from Lettuce for Genetic Identification

Different helminths and protozoa are transmitted to humans by oral uptake of environmentally resistant parasite stages after hand-to-mouth contact or by contaminated food and water. The aim of this study was to develop and validate a method for the simultaneous detection of parasite stages from fresh produce (lettuce) by a one-way isolation test kit followed by genetic identification (PCR, sequencing). Three sentinel zoonotic agents (eggs of Toxocara canis, Echinococcus multilocularis and oocysts of Toxoplasma gondii) were used to investigate the practicability and sensitivity of the method. The detection limits (100% positive results) in the recovery experiments were four Toxocara eggs, two E. multilocularis eggs and 18 T. gondii oocysts (in 4/5 replicates). In a field study, helminth DNA was detected in 14 of 157 lettuce samples including Hydatigera taeniaeformis (Syn. Taenia taeniaeformis) (four samples), T. polyacantha (three), T. martis (one), E. multilocularis (two) and Toxocara cati (four). Toxoplasma gondii was detected in six of 100 samples. In vivo testing in mice resulted in metacestode growth in all animals injected with 40–60 E. multilocularis eggs, while infection rates were 20–40% with 2–20 eggs. The developed diagnostic strategy is highly sensitive for the isolation and genetic characterisation of a broad range of parasite stages from lettuce, whereas the sensitivity of the viability tests needs further improvement.

Exposure to Toxocara spp. and Ascaris lumbricoides infections and risk of allergic rhinitis in children

Background

Substantial experimental studies suggest a role for helminthes infections in the pathogenesis of allergies, but epidemiologic data have been inconsistent. Unlike to asthma, the association between helminthes infection and allergic rhinitis (AR) has been poorly studied. Therefore, we sought to evaluate the association between exposure to Ascaris and Toxocara infections and AR.

Methods

We did an age- and gender-matched case–control study of 81 children with physician-confirmed AR and 101 control subjects in a referral hospital for pediatric diseases in northern Iran. Exposure to Ascaris and Toxocara infections was evaluated by anti-A. lumbricoides- and anti-Toxocara- IgG antibodies using a commercial enzyme-linked immunosorbent assay. Associations were determined using multivariate logistic regression.

Results

Ascaris seropositivity was higher in children with rhinitis than in controls (12.34 vs. 3.96%). Ascaris seropositivity was positively associated with AR in univariate analysis (OR, 3.42; 95% CI 1.03–11.3; P value = 0.035), but this association was not significant after adjustment for potential confounders (OR, 1.85; 95% CI 0.42–8.18). Also Toxocara seropositivity was higher in children with AR than in healthy subjects (3.7% vs. 0.99), indicating non-significant association with AR in both univariate (OR, 3.84; 95% CI 0.39–37.7) and multivariate analyses (OR, 0.8; 95% CI 0.04–15.44).

Conclusion

Our results revealed that AR is not associated with seropositivity to Ascaris and Toxocara infections in general; however, a higher seropositivity rate was found for both parasites in children with AR. More studies with longitudinal design and larger sample size are needed to elucidate this association.

Seroepidemiology of human toxocariasis in selected population groups in Slovakia: A cross-sectional study

BACKGROUND

Human toxocariasis is a cosmopolitan helminthic zoonosis caused by roundworms of the genus Toxocara. The study aimed at a cross-sectional analysis of seropositivity to Toxocara spp. in selected groups of population in Slovakia and an estimate of the risk factors of infection.

METHODS

For the detection of anti-Toxocara antibodies, an enzyme-linked immunosorbent assay (ELISA) based on an excretory-secretory (E/S) antigen of Toxocara canis was used.

RESULTS

The overall seropositivity to Toxocara in 1489 evaluated sera was 3.7%. The seropositivity of Roma children/young people (40.3%) was significantly higher when compared with all other analysed groups. Among adult respondents, the positivity of farmers and hunters (5.5% and 5.1%, respectively) was significantly higher (p<0.001) than in the other analysed groups (veterinarians and veterinary assistants, soldiers, students of veterinary medicine, and students of other universities). Analysis of infection risk factors showed that living in a rural locality, everyday contact with soil, and everyday outdoor activities (12.7%, 8.8% and 8.3% positivity, respectively) can increase the risk of infection, but the observed differences were not significant.

CONCLUSION

The results underline the importance of preventive measures and the need for improving of knowledge of toxocariasis among professionals, as well as the public.

Seroprevalence of Toxocara spp. infection in Southeast Asia and Taiwan

Human toxocariasis is a worldwide neglected zoonotic parasitic disease and caused mainly by Toxocara canis, and to a lesser event, by T. cati. There are only 16 epidemiological studies and 5 clinical toxocariasis case reports in 11 Southeast Asia countries and Taiwan (SEAT) that were found by searching data from PubMed in the period from January 1992 to August 2019. The overall seroprevalence in SEAT varied from 3.9% to 84.6% chiefly detected by using T. canis larval excretory-secretory antigen (TcES)-based ELISA. Playing with dogs or contacting Toxocara eggs from the contaminated soil or vegetables or eating raw meats/viscera containing encapsulated larvae seem likely the major risk factors leading to human toxocariasis in SEAT. Nevertheless, undertaking comprehensive seroepidemiological studies to establish the baseline data and beware of clinical toxocariasis cases by physicians as well as establishing adequate serodiagnostic methods in detection of Toxocara infection, e.g., TcES-based immunoblotting method in helminth endemic SEA are strongly required.

The Roma Population Living in Segregated Settlements in Eastern Slovakia Has a Higher Prevalence of Metabolic Syndrome, Kidney Disease, Viral Hepatitis B and E, and Some Parasitic Diseases Compared to the Majority Population

Background: The Roma population is one of the largest marginalized population groups in Europe. The aim of our work was to summarize the morbidity of lifestyle-related diseases and infectious diseases in the Roma population living in segregated settlements. Methods: We used data from the cross-sectional study HepaMeta, in which we examined 452 Roma subjects with an average age of 34.7 ± 9.1 years, 35.2% of which were men, and 403 non-Roma subjects with an average age of 33.5 ± 7.4 years, 45.9% of which were men. We collected data by means of a questionnaire, anthropometric measures, and we analyzed blood and urine samples. Results: Roma subjects had a higher incidence of metabolic syndrome (RR: 1.478 (1.159-1.885), p < 0.0001), obesity or waist circumference >94 cm in men/80 cm in women (RR: 1.287 (1.127-1.470), p < 0.0001), and HDL-C < 1.03 mmol/L in men or <1.29 in women (RR: 2.004 (1.730-2.321), p < 0.0001) than their non-Roma counterparts. Subjects of the Roma population were more frequently diagnosed with kidney disease (RR: 1.216 (1.096-1.349), p < 0.0001), HBsAg positivity (RR: 4.468 (2.373-8.415), p < 0.0001), anti HBc IgG positivity (RR: 3.13 (2.598-4.224), p < 0.0001), and anti HEV positivity (RR: 2.972 (1.226-7.287), p < 0.0001). Serological markers of Toxoplasma gondii infection and Toxocara spp. were observed much more frequently among Roma than non-Roma subjects (RR: 1.868 (1.520-2.296), p < 0.0001, for Toxoplasma gondii; and RR: 21.812 (8.097-58.761), p < 0.0001, for Toxocara spp.). Conclusions: Poor socio-economic conditions, an unhealthy lifestyle, and barriers precluding access to healthcare are factors that affect the Roma population in settlements and lead to an increased prevalence of metabolic syndrome and its components, kidney disease, viral hepatitis B and E, and some parasitic diseases.

Prevalence of Toxocara spp. in dogs and cats in South America (excluding Brazil)

Toxocariasis is a worldwide anthropozoonosis caused by Toxocara spp. nematodes. High prevalences of the disease has been found in developing countries, particularly in regions with poor sanitary conditions. The definitive hosts of the nematodes are dogs and cats, which play a vital role in the transmission of this parasite as humans are considered a paratenic host. The epidemiology of the disease in South America is not clear as it is usually not diagnosed and is not a notifiable disease. This review summarizes information regarding prevalence reports of Toxocara spp. in dog and cats in South America (excluding Brazil). Additionally, and in accordance with the one health approach, reports of contaminated soil in public zones and parks as well as infection/prevalence reports in wildlife species by geographical regions are also included. The findings show the importance of awareness among veterinarians and public health authorities about Toxocara spp. as neglected disease.

Prevalence and Viability of Toxocara spp. Eggs in Soil of Public Parks in Northwestern Mexico

BACKGROUND

Toxocara spp. is a zoonotic parasite that can infect human; children are the largest group at risk of infection. Therefore, this study aimed to determine the prevalence and viability of Toxocara spp. eggs in the soil of public parks.

METHODS

Overall, 1180 soil samples from 236 public parks in four sectors of the city of Culiacan were collected at random, between Jun and Dec, 2013. The presence of Toxocara spp. eggs was determined by light microscopy using a centrifugation-flotation technique and viability by trypan blue staining technique.

RESULTS

Of the 236 parks sampled, 18 were positive to Toxocara spp. resulting in a prevalence of 7.6% and viability of 94.4% with a P<0.05. Detection of Toxocara spp.in soil samples was 16.5% and viability 94.7% with a P<0.05. Parks positive to Toxocara spp., had sports fields and playgrounds (94.4%), trees and green areas (88.8%).

CONCLUSION

Although a low prevalence of Toxoxara spp. eggs in the soil of public parks was found, they exhibited high viability, suggesting that the soil from these public parks is a source of infection for pets and humans especially children.

Endoparasite infection hotspots in Estonian urban areas

The human-animal bond is beneficial for human health, but companion animals also pose a potential threat as vectors of zoonotic parasites, especially in urban areas where both human and dog densities are high. However, the knowledge about parasitic spillover in the urban environment is relatively scarce. The aim of the present study was to reveal which factors determine parasitic contamination in Estonian towns and provide up-to-date information about intestinal parasites of the Estonian dog population. In total, 657 samples of dog excrement was collected over one year of investigation from five towns in Estonia. Generalized linear mixed models were used to evaluate factors predicting infection risk in urban areas. In general, infection risk and intensity models predicted higher infection with endoparasites for small dogs in smaller towns, especially in apartment-house districts and in potential hazard zones. Helminth eggs and Giardia/Cystoisospora oocysts were detected in 64 samples, with an overall prevalence of 9.8%.

Parasitological contamination with eggs Ascaris spp., Trichuris spp. and Toxocara spp. of dehydrated municipal sewage sludge in Poland

The objective of the present study was to evaluate the contamination of sewage sludge produced by municipal waste treatment plants in Poland by viable eggs of intestinal parasites of the genera Ascaris, Toxocara and Trichuris (ATT). Ninety-two municipal, mechanical-biological sewage treatment plants located within Poland were selected. These plants belonged to types of agglomerations: group 0 (large), group 1 (medium), group 2 (smaller) and group 3 (small). Samples were collected at the final stage of sewage treatment after the addition of flocculent to sludge, followed by dehydration. The samples were examined by a method adjusted to examine sewage sludge dehydrated using polyelectrolytes. The viability of the isolated eggs was evaluated based on incubation in a moist chamber. Live eggs of intestinal nematodes were found in 99% of samples. Most samples were contaminated by the eggs of Ascaris spp. (95%) and Toxocara spp. (96%). However, Trichuris spp. eggs were detected in 60% of samples. The mean number of eggs in 1 kg of dry mass (eggs/kg d.m.) was 5600 for Ascaris, 3700 for Toxocara and 1100 for Trichuris. The highest number of ATT eggs was detected in samples from sewage treatment plants located in south-eastern and central Poland. The highest number of ATT eggs was found in sewage sludge produced in large sewage treatment plants (agglomeration Groups 0 and 1), with mean values of 15,000 and 8900 eggs/kg d.m. The present study is the first parasitological investigation conducted on a large number of samples (92 samples) taken from various types of municipal sewage treatment plants located throughout Poland (16 regions) after the common introduction of polyelectrolytes during sewage sludge dehydration. The results of this study indicate that sludge produced in municipal sewage treatment plants is highly contaminated with parasite eggs.

Investigation on Toxocara spp. eggs in hair coat of dogs in YSR Kadapa district of Andhra Pradesh, India

Present study was aimed to record the Toxocara spp. eggs in dog's hair and to analyze the incidence in breed and age wise along with incidence variations in the anatomical locations of hair over the body. Dogs presented to the hospital were screened for enteric parasitic ova and hair samples were collected from the different body regions including head and neck region, ventral and lateral abdomen, perianal and hindquarters and tail region. Out of the 236 dogs, 124 (52.54%) dogs showed Toxocara spp. eggs in the faecal samples and 60 (25.42%) showed the presence of Toxocara spp. eggs on their hair. It was noticed that the dogs with long hair showed (36.73%) more incidence than the short hair breeds (17.39%). The incidence of the Toxocara spp. eggs were varied with the presence of the hair at different anatomical locations and it was 36.67% in the head and neck region, 51.67% ventral and lateral abdomen, 86.67% in perianal and hindquarters, 56.67% in the tail region. 25.35% of the dogs were under 1-year-old, 25.98% dogs were between 1 and 6 years old and 23.68% dogs were more than 6 years had the Toxocara spp. eggs in their hairs. In conclusion, the presences of Toxocara spp. eggs in the hair of different breeds of dogs were recorded in the present geographical location and it is a zoonotic alert for the pet owners.

Toxocara spp. infection and risk of childhood asthma: A systematic review and meta-analysis

Asthma is one of the most common chronic respiratory disease worldwide, with a negative impact on quality of life and socio-economic status of patients. There are some evidences to suggest that Toxocara infection is a neglected risk factor for childhood asthma. We performed a systematic review and meta-analysis to further understanding of this relationship. Five databases include PubMed, Science Direct, Scopus, Web of Science (ISI), and Google scholar were searched (up to October 2017) to identify the relevant studies. We used random-effects meta-analysis model to estimate the pooled odds ratio (OR) and 95% confidence intervals (CI). Heterogeneity was assessed with the Q-test and I² statistic. A total of 17 studies including 11 studies with case-control design (1139 patients and 1023 controls) and six studies with cross-sectional design (a total of 5469 participants, 872 asthmatics, and 4597 non-asthmatics children) met the eligibility criteria. An increased risk for asthma was observed in children with Toxocara infection seropositivity (OR, 1.91; 95% CI, 1.47-2.47). In sub-group analysis, the pooled ORs were (OR, 2.13; 95% CI, 1.43-3.15) and (OR, 1.73; 95% CI, 1.23-2.44) for case-control and cross-sectional studies, respectively. Moreover, considering to specific IgE seropositivity, a pooled OR of 2.36 (95% CI, 0.93-5.98) was observed. In conclusion, this meta-analysis revealed that children infected with Toxocara spp. are more likely to have asthma compared to non-infected children. More studies (especially longitudinal studies) are needed to further investigate the impact of Toxocara spp. infection on the onset or development of asthma.

Helminth Fauna in Captive European Gray Wolves (Canis lupus lupus) in Germany

Captive as well as free-ranging wolves, which are currently recolonizing Germany, may harbor a variety of gastrointestinal parasites. This study investigated endoparasites in captive European gray wolves (Canis lupus lupus) using coproscopical methods. Fecal samples were collected monthly between October 2012 and November 2013 from 18 wolf enclosures in 14 German zoological gardens, representing 72 individual wolves. In total, 1,041 fecal samples including 26 bulk samples were analyzed by the sedimentation and flotation method. The most frequently detected egg morphotypes included five nematodes [Ancylostomatidae (Ancylostoma or Uncinaria spp.), Toxocara canis, Toxascaris leonina, Trichuris vulpis, and Capillaria/Eucoleus spp.], one cestode (Taeniidae) and one trematode (Alaria alata). 44.76% of all samples were positive for at least one of these egg morphotypes. Overall, Ancylostomatidae showed the highest frequency (30.84% of all samples), followed by Capillaria/Eucoleus spp. (19.88%), Toxocara canis (5.19%), taeniids (3.75%), Trichuris vulpis and Alaria alata (3.65% each), and Toxascaris leonina (1.25%). As fecal samples were collected from the environment and could not be assigned to individual wolves, sample results were combined per zoo and month. General linear mixed models were employed to analyze the effect of season and management factors on the occurrence of Ancylostomatidae, Capillaria/Eucoleus spp., Toxocara canis and taeniids. No statistically significant effect of season was found, whereas anthelmintic treatment negatively affected Ancylostomatidae egg excretion. Detected parasites and their prevalences are comparable to previous studies on wolf parasitism conducted elsewhere in Europe. As many of the most prevalent helminths are of zoonotic importance, routine anthelmintic treatment of captive wolves should be recommended.

Clinical usefulness of Western blotting and ELISA avidity for the diagnosis of human toxocariasis

The serodiagnosis of human toxocariasis is difficult. Specific IgGs detected routinely with ELISA based on Toxocara excretory-secretory (TES) antigens often persist for years at an elevated level, which does not allow either the differentiation between an active and persistent infection or monitoring of the effect of treatment. Additionally, false-positive results may occur in co-infections with other helminths due to cross-reactions. We evaluated the usefulness of an IgG avidity index (AI) and a Western blotting (WB) IgG in the diagnosis of patients suspected of Toxocara infection. We studied 138 subjects who were submitted to serological testing two or more times. Confirmation of an infection by WB was achieved in 73.2% of patients. A high AI was obtained in 89.1% of patients, and low AI and borderline AI were found in only 10.9%. Low and borderline values of AI remained at similar levels in subsequent studies over 2-3 years. The results showed the necessity of obligatory verification of all ELISA IgG positive and questionable results by WB. The index of IgG avidity may be helpful in excluding recent infection, but its usefulness in detecting an active phase of invasion requires further research.

Frequency of Toxocara spp. antibodies in umbilical cords of newborns attended atthe University Hospital in Southern Brazil and factors associated with infection

Toxocariasis is a neglected and geographically widespread parasitic disease. The detection of specific antibodies associated with this disease is required to confirm its clinical diagnosis and to aid in prevention. Although helminth infection during pregnancy can promote foetal immune responses with long-term effects, specific information regarding the risk of Toxocara spp. infection to the human foetus during pregnancy is lacking. Therefore, the present study aimed to investigate the frequency of antibodies against Toxocara spp. in umbilical cord serum samples to determine the neonatal risk factors associated with Toxocara spp. infection. A cross-sectional study of the frequency of specific antibodies against Toxocara spp. was performed on umbilical cord samples of 280 neonates. A cord blood sample was obtained from each newborn after parturition, and serum samples were examined by enzyme-linked immunoassay. Epidemiological data were obtained through a questionnaire regarding obstetric history (abortion history, premature birthhistory, and pregnancy and birth numbers), general aspects (animal contact anddiet) and socio-economic factors. The frequency of anti-Toxocara spp. IgG antibodies in the umbilical cords of neonates was 20% in serum pre-adsorbed with Ascaris spp. antigen. Family income and dog ownership were considered risk factors associated with infection. No association was found between reproductive disorders and Toxocara seropositivity. The 20% frequency rate of anti-Toxocara spp. IgG antibodies in sera from umbilical cords of newborns can be related to IgG binding at the maternal-foetal interface, requiring greater care during pregnancy. Anti-Toxocara IgM and IgE antibodies no were found in umbilical cord serum samples, indicating that no vertical transmission of these parasites occurred in this population. Studies regarding antibodies against Toxocara spp. in umbilical cord sera are important for determining neonatal exposure to these parasites.

Detection of Toxocara spp. Eggs in the Soil of Public Places in and Around of Ardabil City, Northwestern Iran

BACKGROUND

Human toxocariasis is contained in the list of neglected diseases. The infection occurs after ingestion of embryonated eggs in contaminated soil. The present study was carried out to estimate the extent of soil contamination with Toxocara spp. eggs in the public places.

METHODS

Soil samples were collected randomly from 41 public places in various parts in and around of Ardabil, Iran, between March 2013 and March 2014. Data were examined by microscopy following sodium nitrate flotation.

RESULTS

Of the 200 collected soil samples, 35 (17.5%) were positive for soil parasites. The eggs of Toxocara spp. were found in 14 (7%) soil samples.

CONCLUSION

This investigation gives baseline knowledge regarding soil contamination with Toxocara spp. eggs in Ardabil city and provides information for local control of toxocariasis.

Production of interleukins 4 and 10 in children with hepatic involvement in the course of Toxocara spp. infection

Toxocara spp. infestations present with a wide spectrum of symptoms, from general inflammation of internal organs with eosinophilic granuloma formulation through ocular or brain involvement. There is also an asymptomatic form. The known factors that influence the clinical form of the disease are the intensity of the infestation, the localization of the larvae, the age of the patient, the efficiency of the immune system and the history of reinfection. The aim of our study was to evaluate the production of interleukins 4 (IL-4) and 10 (IL-10) in children in the course of Toxocara spp. infections with hepatic involvement. The analysis of peripheral leucocytes, eosinophils, immunoglobulin E, and IL-4 and IL-10 concentrations presented significantly higher values in children with radiologically confirmed liver granuloma than in uncomplicated hepatomegaly. Based on statistical analysis, we confirmed the IL-4/IL-10 ratio variation in the analysed groups: patients with liver lesions showed a ratio of <1, while children without granulomas had a ratio of >2. The relevant analysis confirmed a positive statistical correlation in both seropositive groups for IgE and IL-4, and only in the granuloma group for IgE and IL-10.

Seroprevalence and Associated Risk Factors of Toxocariasis among College Students in Taipei City, Taiwan

BACKGROUND

Infection by Toxocara spp. is known to be significantly associated with partial epilepsy. It has become popular for people to raise dogs/cats as pets and consume roasted meat/viscera, and the status of Toxocara spp. infection, epilepsy awareness, and associated risk factors among the general population are currently unknown in Taiwan.

METHODS

A seroepidemiological investigation among 203 college students (CSs), consisting of 110 males and 93 females with an average age of 21.5 ± 1.2 years, was conducted in 2009 in Taipei City. A Western blot analysis based on excretory-secretory antigens derived from Toxocara canis larvae (TcESs) was applied to determine the positivity of serum immunoglobulin G antibodies. A self-administered questionnaire was also given to obtain information about demographic characteristics, epilepsy awareness, and risk factors. A logistic regression model was applied for the statistical analysis using SPSS software.

RESULTS

The overall seropositive rate of Toxocara spp. infection was 8.4% (17/203). As to epilepsy awareness, a non-significantly higher seroprevalence was found in CSs who claimed to "know" about epilepsy compared to those who did not know (P > 0.05).

CONCLUSIONS

It appears that appropriate educational programs are urgently needed to provide correct knowledge related to the prevention and control measures against Toxocara spp. infections to avoid potential threats by this parasite to the general population in Taiwan.

The relation between the prevalence of soil transmitted parasites in the soil and among school children in Zagazig district, Sharkyia Governorate, Egypt

Soil transmitted helminths are highly prevalent throughout the developing countries of the world and Egypt is categorized as one of the developing countries. This study aimed to detect the relation between the presence and prevalence of STH in the soil and their reflection on the prevalence among school-children living in rural and urban areas in Zagazig district, Egypt. The present study was carried out on (859) school-children aged 6-13 years in Zagazig district all over the year 2013. They were subjected to stool examination. Out of them 100 suspected children were serotested for anti-TES IgG antibodies Toxocara spp. Soil samples also were collected from their places and regions. The results showed overall prevalence of parasitic infections was 21.07 % for helminthic infection and 39.46 % for protozoa. The prevalence of parasitic infections was more among children in rural areas (28, 49.2, 11.1 %) than those who live in urban areas (6.4, 18, 2.2 %) for helminths, protozoa and Toxocara as the most prevalent helminth respectively. Highly significant association was found between soil-transmitted helminthic infections detected by stool examination of the studied children group and the prevalence of geohelminthes in the examined soil samples, taken from residency areas of those children. This association was missed regarding protozoal infections. According to the results, low level of education and consequently poor socio-economic and hygienic conditions of families appear to be powerful determinants of infection. Thus, improving environmental sanitation is imperative for the control of soil-transmitted helminths.

A case of ocular toxocariasis successfully treated with albendazole and triamcinolon

We present a case of ocular toxocariasis treated successfully with oral albendazole in combination with steroids. A 26-year-old male visited the authors' clinic with the chief complaint of flying flies in his right eye. The fundus photograph showed a whitish epiretinal scar, and the fluorescein angiography revealed a hypofluorescein lesion of the scar and late leakage at the margin. An elevated retinal surface and posterior acoustic shadowing of the scar were observed in the optical coherence tomography, and Toxocara IgG was positive. The patient was diagnosed with toxocariasis, and the condition was treated with albendazole (400 mg twice a day) for a month and oral triamcinolone (16 mg for 2 weeks, once a day, and then 8 mg for 1 week, once a day) from day 13 of the albendazole treatment. The lesions decreased after the treatment. Based on this study, oral albendazole combined with steroids can be a simple and effective regimen for treating ocular toxocariasis.

Molecular characterization of Toxocara spp. from soil of public areas in Ahvaz southwestern Iran

In the present study, the microscopy and polymerase chain reaction methods were used for detection and identification of soil contamination by Toxocara eggs in squares, streets, public parks, and rubbish dumps in Ahvaz, southwestern Iran. A total of 210 soil samples were collected from different parts of the city and examined by microscopy and polymerase chain reaction (PCR) methods, following sodium nitrate flotation. Nucleotide sequencing was performed to confirm the results of the PCR method. Toxocara eggs were found in 64 and 71 soil samples using the microscopy and PCR methods, respectively. The highest contamination rate was observed in the central part of Ahvaz (39.5% and 46.5% by the microscopy and PCR methods, respectively). Based on internal transcribed spacer 2 (ITS2) PCR identification, 28% of the samples were diagnosed as Toxocara cati and 5.7% as Toxocara canis; no mixed contamination was observed. DNA sequencing of the ITS2 gene confirmed our findings. Compared to the conventional microscopic detection following by flotation, used as the gold standard, the PCR method appears to be rapid and sensitive as well as allows analysis of Toxocara spp. isolated from soil independent of the stage of egg development. Therefore, the PCR method appears to be a valuable tool for the diagnosis and differentiation of Toxocara spp. from soil samples in epidemiological studies, and will help the local health systems in effective prevention and control of disease.