Human Toxocariasis Research Articles

Nematode Toxocara canis as a Probable Epidemic, Sanitary and Hygienic Threat to Public Health in the Southern Region of the Russian Federation

Introduction: According to the World Health Organization, Toxocara canis, a nematode in the order Ascarididia, is an epidemic and epizootic risk factor for humans and animals around the world and in the Russian Federation. Human toxocariasis is one of the commonest parasitic zoonoses with up to 900 million incident cases registered annually in different age and social groups of the population and a global public health problem of our time. Objective: To study the nematode Toxocara canis (Werner, 1782) as a health risk factor for the population of southern regions the Russian Federation. Materials and methods: We estimated the incidence of larval toxocariasis in the population of 10 districts and two cities of Karachay-Cherkessia based on the results of enzyme immunoassay of blood samples of 6,000 people in 2019–2022. The Tiascar diagnostic test kit (2017) was applied showing toxocariasis for the antibody titer ≥ 1:800 and infestation with Toxocara larvae for those of 1:200 and 1:400. The stool ova and parasite test was used to study 600 dog stool samples from the study areas. In addition, 1,200 soil samples were tested for the presence of Toxocara canis eggs. Results: We established that the incidence rate of larval toxocariasis in the population of 10 districts and two cities of Karachay-Cherkessia varied from 2.00 to 5.40 %. Toxocara canis larvae were not found in human feces, since humans are a biological dead end for this species of worms. Toxocara canis infestation rates in feces of dogs ranged from 2.7 ± 0.4 to 6.9 ± 0.8 eggs/g, potentially accounting for a high level of soil contamination with eggs. The current epidemic situation of human toxocariasis in the Karachay-Cherkess Republic is relatively favorable owing to planned preventive measures. Yet, this constituent entity is at risk of the disease in the future since the number of children, adults and migrants with larval toxocariasis shows a dynamic growth throughout the year. Conclusion: Incidence rates of larval toxocariasis in the child population and migrants demonstrate a 2.74–2.78-fold increase during the year. Toxocara canis eggs contaminate 46 to 94 % of soils in different areas of the republic posing high risks of larval toxocariasis for the local population. In terms of canine toxocariasis, the Karachay-Cherkess Republic can be attributed to disadvantaged territories of the North Caucasian Federal District.

Association between seropositivity for toxocariasis and cognitive functioning in older adults: an analysis of cross-sectional data from the US National Health and Nutrition Examination Survey (NHANES), 2011–2014

ObjectivesThis study sought to examine the relationship between seropositivity for toxocariasis and cognitive functioning in a nationally representative sample of US older adults.DesignA cross-sectional study.SettingNational Health and Nutrition Examination Survey...

Environmental Toxocara spp. presence in crowded squares and public parks from San Juan Province, Argentina: A call for a "One Health" approach.

Canine soil-transmitted helminth (cSTH) parasites need specific environmental conditions to complete their life cycle. Toxocara canis and T. cati are the most important zoonotic cSTH, since they are the causal agents of human toxocariasis. Canine STHs are dispersed in feces from infected domestic and wildlife canines. In this study, the presence of STH in canine feces was evaluated in 34 crowded public parks and squares from San Juan Province (Argentina). Fecal samples were collected during different seasons in 2021-2022 and analyzed by standard coprological methods, including Sheather and Willis flotation and Telemann sedimentation. InfoStat 2020, OpenEpi V. 3.01 and R and RStudio® were used for statistical analysis and QGIS 3.16.10 for mapping. From a total of 1,121 samples collected, 100 (8.9%) were positive for at least one intestinal parasite (IP) and three cSTH species were detected: Toxocara spp., Toxascaris leonina and Trichuris vulpis. The most prevalent cSTH species was T. vulpis (64/1121; 0.057%), while the least prevalent was Toxocara spp. (19/1121; 0.017%). The detection of Toxocara spp. eggs was significantly different depending on the season. The geo-spatial variation of each cSTH per season is described. This is the first study in San Juan Province to identify environmental contamination of cSTHs in public areas. The specific localization of areas with the presence of cSTH eggs could provide information to guide strategies to reduce the cSTH infection burden in dogs and promote serological screening of the human population for Toxocara spp. Given the zoonotic nature of Toxocara spp. We hope this information will help to reinforce activities of control programs, focusing on the "One Health" approach.

Gastrointestinal Parasites of Dogs in Egypt: An Update on the Prevalence in Dakahlia Governorate and a Meta-Analysis for the Published Data from the Country.

Since the last survey on gastrointestinal (GIT) parasites infecting dogs in Dakahlia governorate, Egypt, was published 40 years ago, the present study detected various GIT parasites in feces of 78 stray dogs in this governorate. Twenty-one dogs (35.9%) had eggs/oocysts of eight different parasites including Toxocara canis (19.2%), Toxascaris leonina (2.6%), hookworms (1.3%), Taenia species (5.1%), Dipylidium caninum (2.6%), Cystoisospora canis (5.1%), Cystoisospora ohioensis (2.6%), and Neospora caninum-like oocysts (1.3%). These results were combined in various meta-analyses with findings of all published surveys on GIT parasites of dogs in Egypt to underline the potential parasitic zoonoses from dogs in the country. Feces and/or gastrointestinal tracts of 19,807 dogs from various Egyptian governorates, but particularly Cairo, have been microscopically tested in 182 datasets published between 1938 and 2022, revealed during our systematic database search. Toxocara canis, interestingly, displayed a twofold higher pooled prevalence (24.7%) when compared to the published global pooled prevalence for T. canis, indicating that dogs represent a major risk for toxocariasis in humans from Egypt. Dipylidium caninum (25.4%) as well as various Taenia species (17.1%) also displayed high pooled prevalences. On the contrary, lower pooled prevalence was estimated for the most important zoonotic taeniid "Echinococcus granulosus" (2.4%) as well as for hookworms (1.8%) in comparison to what has been published from other countries in the region. Relatively high prevalences were estimated for three protozoa detected in dogs and are common to infect children in Egypt; Cryptosporidium (5.5%), Giardia (7.4%), and Entamoeba histolytica (9.8%). In general, the pooled prevalence estimated for various parasites detected in dogs from Egypt has decreased in the recent years, sometimes by as much as one-fifth, but this great decline is statistically insignificant, which should alert the veterinary and public health authorities to continue their efforts for controlling these parasites in a "One Health" approach.

Molecular surveillance detects the zoonotic nematode parasite Toxocara in soils from public spaces in a Minnesota community

Toxocara canis and Toxocara cati are common nematode parasites of dogs and cats, and are capable of causing a variety of pathologies in humans. Human toxocariasis is a ubiquitous and likely under-diagnosed public health concern across the globe. Examination of soils in numerous public spaces worldwide readily detect Toxocara eggs and serological studies indicate a substantial exposure to this parasitic roundworm in human populations. This study sought to determine whether genetic evidence of pathogenic Toxocara species could be found in soils from local public spaces in a Minnesota community. Total genomic DNA was purified from soil samples obtained from public parks and PCR was performed using primers specific to either T. canis or T. cati. Genetic evidence for both species of Toxocara was found in soils surveyed. T. canis was identified in five of 12 public spaces surveyed and T. cati was present in two of the same 12 public spaces. Although the infectious potential of the Toxocara identified was not determined, the presence of this parasite in locations amenable to transmission to humans indicates the need for proper veterinary care of domestic dogs and cats as well as a greater emphasis on public health education and actions to prevent human infection.

Toxocara Infection in Dogs and Cats in Isfahan Province of Iran in 2021.

Toxocariasis is an acute or chronic disease caused by parasites of the Ascaridae family, especially Toxocara of dogs and cats. Eggs are excreted out by feces of these animals on soil. Infective eggs develop on soil which can be infective to human. In this study, infection rate of Toxocara spp. in dogs and cats of urban and rural areas of Isfahan province of Iran has been investigated. Three hundred and seventy-five stray dog feces and 230 stray cat feces were collected from the public environment (slaughterhouses, parks, children's playgrounds, student dormitories, university environment, streets and squares) in Isfahan province of Iran. At first, dogs' and cats' feces were examined for the presence of Toxocara spp. eggs using formalin ether method. In the second stage, by using molecular methods, Toxocara eggs spp. (Toxocara canis or Toxocara cati) were identified. From 375 dog fecal samples, 39 (10.40%) and from 230 cat fecal samples, 38 (16.52%) were positive for presence of the Toxocara eggs. Dogs and cats in Isfahan province of Iran were infected with Toxocara parasite. These infections can be potential risk for human toxocariasis.

Toxocariasis in Ghanaian neighbourhoods: a need for action

BackgroundAnimal reservoirs of Toxocara spp., a neglected parasitic infection, are frequently found in many Ghanaian neighbourhoods. Despite various interactions occurring between these animals and humans which sustain zoonosis, not much focus has been directed at disease surveillance in Ghana, necessitating this study. MethodsThe study was cross-sectional. It combined the collection of biological samples with the survey approach. The study used purposive and convenience sampling techniques to collect data from eligible participants in the Greater Accra region of Ghana. Besides the collection of biological samples from animals which were processed using molecular techniques, semi-structured questionnaires were administered to the pet owners. ResultsIn sum, 32.2% (95% CI, 27.6%–37.0%) of the targeted animals were positive for Toxocara canis, with most of the cases being found in dogs and rodents. Among the 204 rodents, more Praomys tulbergi were positive for this parasite compared to the others. From the survey, some risk factors culminating in high disease exposure were identified: more than one-third of pet owners did not deworm their pets although about a fourth shared bed with them. In addition, many respondents’ kids played with these pets but not all supervised them to practice hand hygiene. Also, a good number of pet owners confirmed the frequent exposure of their pets to rodents. ConclusionsThe relatively high prevalence of T. canis recorded in animals and the increasing exposure of humans to this parasite point to a higher risk for human toxocariasis. Furthermore, T. canis found in cats cannot be ignored and merits further investigations. For Ghana to achieve SDG 3 by 2030, priority must also be placed on neglected diseases which calls for an integrated approach to disease surveillance and a redirection of research focus using the one health concept.

Human Toxocariasis: Dog and Cat Keeping as a Risk Factor

Human Toxocariasis: Dog and Cat Keeping as a Risk Factor

Evaluation of new Toxocara canis chimeric antigens as an alternative to conventional TES-Ag for anti-Toxocara antibodies detection

Human toxocariasis is one of the neglected helminthiases and it is caused by the zoonotic roundworm species Toxocara canis and Toxocara cati. Diagnosis of human toxocariasis is based on the combination of clinical, parasitological, and epidemiological criteria, as well as serology tests that detect anti-Toxocara antibodies. Notwithstanding, due to the absence of pathognomonic symptoms and signs of the disease, serology is the key evidence to support a conclusive diagnosis. TES-ELISA is the most widely used serological test for diagnosis. However, cross-reaction of TES antigens with antibodies produced to other helminth antigens is a major drawback for its application in countries with high parasitic prevalence. T. canis recombinant antigens have been described as an alternative to native TES for diagnosis. Nevertheless, the selection of antigenic proteins is a complex process that requires validation. In this paper, we developed an eGFP carrier-based system to express and purify blocks of recombinant polypeptides of T. canis antigenic proteins. Intense cross-reaction polypeptides were detected by Immunoblot and avoided to finally produce a chimeric prototype protein. Additionally, a control chimeric protein that harbors the complete tested proteins was produced. Purified chimeric antigens were tested in ELISA and Immunoblot assays with 310 sera samples of negative and positive control individuals. Our results showed that chimeric rCHITC0 and rCHITC1 antigens (with sensitivities of 62% 58%, 38% and 16% in IB-rCHITC0, ELISA-rCHITC0, ELISA-rCHITC1 and IB-rCHITC1 respectively for OLMS) can perform better in terms of specificity (being 91%, 89%, 87% and 76% for ELISA-rCHITC1, IB-rCHITC1, ELISA-rCHITC0 and IB-rCHITC0 respectively for OLMS) than T. canis TES-ELISA (with 61% specificity), giving a higher signal with serum samples of infected individuals as well the possibility to discriminate false positive cases with other parasitic infections. Our data suggest that T. canis chimeric proteins, represent candidate antigens for phase II studies.

Eosinophilic Pneumonia Due to Toxocariasis: A Rare Case Report in a Paediatric Patient and Literature Review

Human toxocariasis is a zoonosis caused by the larvae of Toxocara genus parasites. It is usually asymptomatic and self-limiting. However, due to either the direct action of parasites or by immunological mechanisms, it can affect several organs resulting in many clinical manifestations. Among paediatric patients, lung involvement occurs in 20–85% of cases of visceral toxocariasis, as Löffler’s syndrome, chronic pneumonia, eosinophilic pneumonia, or baby wheezing syndrome. Because of its rarity, eosinophilic pneumonia due to Toxocara larvae is not well-documented amongst medical records. This article presents a clinical case of a 2-year-old with a history of daily sand and soil ingestion, followed by sudden pulmonary symptoms, 9-day fever, abnormal chest X-ray, and intense peripheral eosinophilia. Due to the suspicion of toxocariasis pneumonia after a series of laboratory tests, the diagnosis of eosinophilic pneumonia caused by the parasite was confirmed. After treatment with albendazole for 5 days, the patient displayed progressive improvement in respiratory symptoms and a reduction in peripheral eosinophilia.

Risk Factors and Prevalence of Toxocariasis in Healthy Adults in South Khorasan Province, Eastern Iran

Background: Toxocariasis is a common zoonotic helminthic disease with worldwide distribution. Seroepidemiological data related to human toxocariasis and its risk factors are limited in the east of Iran. Objectives: The current study evaluated the seroprevalence of toxocariasis and associated risk factors in clinically healthy individuals aged 18 years or older in eastern Iran. Methods: We took 450 samples from clinically healthy individuals referred to medical laboratories for health screening between March and May 2022 in Birjand, Iran. The seroprevalence of IgG antibody against Toxocara was performed using the enzyme-linked immunosorbent assay (ELISA) kit (IBL, Germany). Logistic regression was used to analyze the association between toxocariasis and potential risk factors by SPSS 21.0 software. A probability P value less than 0.05 was considered statistically significant. Results: The sample included 210 (56.6%) men, and 240 women (53.3%) who were aged 18 to 81 years (mean 35 ± 13 years). The Toxocara ELISA was positive in 36 (8%) individuals. The statistical analysis showed that washing hands before eating (odds ratio (OR) = 0.1, 95% CI: 0.05 - 0.3, P < 0.0001), contact with cats and dogs (OR = 0.1, 95% CI: 0.05 - 0.3, P < 0.00001), and raw meat consumption (OR = 4.8, 95% CI: 2.2 - 11.4), P < 0.0004) were risk factors associated with Toxocara infection. Conclusions: The relatively low seroprevalence of Toxocara infection in our study can be caused by environmental and socio-cultural conditions and moderate to high hygiene standards in Birjand. It is suggested that more extensive studies be conducted with larger sample sizes in at-risk groups in this area.

A Retrospective Study of the Efficacy of Albendazole and Diethylcarbamazine for the Treatment of Human Toxocariasis.

In the Department of Parasitology and Mycology of Toulouse University Hospitals, patients presenting with common/covert toxocariasis were treated either with albendazole (39 cases) or with diethylcarbamazine (32 cases). Albendazole (ABZ) was given at 10 mg/kg b/w daily for 14 days, and diethylcarbamazine (DEC) was given at 4 mg/kg b/w daily for 21 days. In both groups, follow-up consultations occurred approximately 48 days after the end of the anthelmintic therapy. ABZ and DEC displayed a similar efficacy on the kinetics of the clinical picture (−64.5% of reduction vs. −72.7%, respectively) and on the levels of blood eosinophilia, serum eosinophil cationic protein and serum total IgE. However, the effect of the medication on the laboratory parameters was moderate. The rate of adverse reactions was similar in both groups (38% for ABZ vs. 31% for DEC), but DEC-treated patients complained of more intense and long-lasting side effects. The DEC group had more major adverse reactions, resulting in the termination of the anthelmintic treatment. The results from this retrospective study bring further arguments for considering ABZ, given at 10 mg/kg daily for 2 weeks, as the drug of choice in the treatment of human toxocariasis.

Larva migrans in BALB/c mice experimentally infected with Toxocara cati ensured by PCR assay

BackgroundToxocara cati, the cat roundworm, is a parasitic nematode that known to cause toxocariasis in intermediate hosts and humans. In this study, we characterized the dynamics of T. cati larvae migration in BALB/c mice after inoculation with eggs and ensured the migration detecting the larval DNA by a PCR. To evaluate the dynamics of larval migration and distribution, twenty-four BALB/c mice were orally inoculated with 2500 T. cati infective eggs and the visceral organs of the infected animals were examined by pepsin digestion and microscopic parasite counts, followed by PCR at day 1 to 28 post-inoculation.ResultsThe PCR assays were successfully used for detection of T. cati larvae in tissue samples and T. cati larvae and the DNAs were found in the liver, lungs, heart, kidneys and the brain. We detected T. cati in 92.2% of tissue samples by PCR, 30% higher than the conventional pepsin digestion technique.ConclusionOur findings demonstrated that the PCR assay is a sensitive and specific for the detection of T. cati larvae. Therefore, it could become a useful tool for the investigation of the dynamics of larval migration and Toxocara infection in murine model.

Seroprevalence of toxocariasis among allergic patients in Kuwait and its association with eosinophilia

Toxocariasis is a worldwide helminthic infection which is transmitted from infected dogs and cats and has been associated with peripheral blood eosinophilia. The Centers for Disease Control and Prevention (CDC) placed toxocariasis among the top 6 parasitic diseases in the USA which are prioritized for public health action. To our knowledge, there are no reports on human toxocariasis in Kuwait or in the other Gulf Cooperation Council (GCC) countries. This study aims at investigating the seroprevalence of toxocariasis among allergic patients in Kuwait and its association with eosinophilia, age, gender, nationality, and history of direct contact with dogs or cats. From September to December 2021, the laboratory records of allergic patients referred to Al-Rashed Allergy Hospital, Kuwait were reviewed and a total of 400 serum samples were selected: 200 samples from patients with normal eosinophil count (< 500 cells/μl) and 200 samples from patients with eosinophilia (> 500 cells/μl). The sera were screened for anti-Toxocara canis IgG antibodies via antibody enzyme-linked immunosorbent assay (Ab-ELISA). The seropositive patients were asked about their history of direct contact with dogs or cats. Statistical analyses were performed using Microsoft Excel® Analysis ToolPak software. Toxocariasis seropositivity was detected in 10 out of 400 (2.5%) allergic patients. Five patients had eosinophilia while 5 had normal eosinophil count. There was no difference in mean age or gender between Toxocara-seropositive and seronegative patients (p > 0.05). The seroprevalence rate was lower-than-expected among Kuwaiti patients (2/307, 0.7%) in comparison with non-Kuwaiti patients (8/57, 14.0%) (χ2 = 33.603, df = 1, p < 0.001) who originated from endemic South/Southeast Asian countries. Seven out of 8 (87.5%) seropositive patients had a history of direct contact with cats, dogs, or both. The seroprevalence rate of toxocariasis among allergic patients in Kuwait was 2.5%. Raising awareness and early deworming treatment/prophylaxis for juvenile dogs and cats remain crucial for toxocariasis prevention.

Dog and Cat Contact as Risk Factor for Human Toxocariasis: Systematic Review and Meta-Analysis.

Toxocariasis, a neglected parasitic zoonosis with worldwide distribution, has been reportedly associated to different risk factors in several epidemiological and meta-analysis studies. However, dog and cat contact (environmental and animal exposure) as isolated associated risk factor for children and adults remains to be fully established. Accordingly, the present meta-analysis has aimed to directly assess dog and cat contact for toxocariasis seropositivity in under-18 and adult persons, using a survey strategy of PubMed/Medline, Embase, Scopus and Scielo Databases, from January 2009 to December 2021. A meta-analysis model of random effects was applied to estimate odds ratio (OR) with 95% Confidence Interval (CI). The statistical heterogeneity was evaluated by the Cochran Q-Test and I2 values. A total of 41 transversal studies (n = 20.515 individuals) from different geographic regions (classified by the World Health Organization) were included herein. In overall, 1,882/13,496 (13.95%; 95% IC = 13.4–14.5) youngers and 513/7.019 (7.3%; 95% CI = 6.7–7.9) adults in contact with dogs or cats were serologically reagent for anti-Toxocara antibodies. Association of dog and cat contact was observed only in youngers, with both dogs (OR = 1.53; p < 0.0001) and cats (OR = 1.64; p = 0.0001). In addition, association of dog and contact and serology was statistically significant in populations of Americas (OR = 1.37; 95% CI = 1.1–1.7), Middle East (OR = 2.9; 95% CI = 1.6–5.1) and West Pacific (OR = 1.6; 95% IC = 1.3–1.9). In conclusion, contact with dogs and cats, particularly by younger individuals and in regions such as Americas, Middle East, and West Pacific, should be always a public health concern for toxocariasis. Moreover, dogs and cats should be periodically dewormed, washed and hair cleaned prior to contact with youngers. Finally, robust statistical results herein may serve as basis for future strategies and preventive measures for safer dog and cat contact.

#37 Human Toxocariasis: eleven-year experience in a tertiary-care level pediatric hospital in Mexico City

Abstract Background In Mexico, human toxocariasis is not subject to continuous epidemiological surveillance. However, some studies that report seroprevalence show a significant association between larva migrans (LM) and pediatric cases (OR 3.2; IC95 2.541-4.279). Data is scarce about infection in animal reservoirs, more specifically dogs, in which there are reports of a 12-18% positivity rate. As for the role of the environment there is evidence to support high contamination levels. Most symptomatic pediatric patients develop ocular presentations that can lead to permanent vision loss, and diagnosis becomes a challenge because serological markers and peripheral eosinophilia can be absent. Method A retrospective, transverse, descriptive study including 17 patients with diagnosis of toxocariasis according to electronic medical records. For categoric variables, frequencies and percentages were analyzed and for discrete variables median and ranges were calculated. Results Nine patients (52.9%) presented with ocular LM of which, 55.6% were female with a median age of 5 years at diagnosis (IQR=9). 44.4% came from the coastal state of Veracruz and 88.9% had close contact with either dogs or cats. Two patients presented with eosinophilia and only one had positive anti-Toxocara antibodies at 2.12 OD. Under suspicion of retinoblastoma, two patients underwent enucleation and diagnosis was made with pathology findings. Eight patients (47.1%) presented with visceral LM of which, 62.5% were female with a median age of 7.5 years at diagnosis (IQR=12). 62.5% of them had close contact with either dogs or cats. In this case, all patients had history of peripheral eosinophilia but it was only in 75% that it was corroborated during initial workup at our institution ranging between 500-9400 cells/mm3 and all of them had positive antibodies that ranged between 1.02-3.2 OD. Five patients received oral treatment with albendazole for 3-7 days. Conclusion Human toxocariasis is a neglected parasitic disease with scarce published data. Pediatric patients are an important vulnerable group specially for ocular presentations. The differential diagnosis of leukochoria should always include retinoblastoma, but as shown in this study, also ocular LM. As new approaches to global health move towards prevention, our study can set a precedent in order to standardize patient care and resource allocation.

Toxocara canis Infection Alters mRNA Expression Profiles of Peripheral Blood Mononuclear Cells in Beagle Dogs at the Lung Infection Period.

Simple SummaryToxocariasis is one of the most neglected zoonoses in the world. Toxocara canis is the main pathogen causing toxocariasis in humans and animals, threatening public health. To date, the mechanism by which the larvae of T. canis escape the attack of immune cells in the blood is still poorly understood. Using RNA-seq technology, the transcriptional alterations of Beagle dog peripheral blood mononuclear cells (PBMCs) between the presence and absence of T. canis infection were analyzed during the lung infection period, and 1066 upregulated genes and 1076 downregulated genes were identified (padj < 0.05 and |log2 (FoldChange)| > 1). In addition, many immune- or inflammation-related GO terms and KEGG signaling pathways were significantly altered during T. canis infection by GO annotation and KEGG enrichment analysis. The present study revealed that T. canis infection can alter the mRNA profiles of PBMCs in Beagle dogs during the lung infection period, which has important implications for a better understanding of the interaction mechanism between T. canis and host immune cells.Toxocara canis is a neglected zoonotic roundworm distributed all over the world, causing toxocariasis in humans and animals. However, so far, the immune mechanism of T. canis infection in definitive hosts remains to be clarified. In this study, the transcriptional alterations of Beagle dogs’ peripheral blood mononuclear cells (PBMCs) induced by T. canis infection during the lung infection period were analyzed using RNA-seq technology. A total of 2142 differentially expressed genes were identified, with 1066 upregulated genes and 1076 downregulated genes. Many differentially expressed genes participated in the biological process of intracellular signal transduction, as well as the immune- or inflammation-related KEGG signaling pathway, such as the Notch signaling pathway, Toll-like receptor signaling pathway, and NF-kappa B signaling pathway, through KEGG enrichment analysis. This study indicated that T. canis infection could suppress the biological function of Beagle dogs’ PMBCs and provided basic data to further clarify the interaction mechanism between T. canis and host immune cells.

Indirect immunofluorescence assay using embryonated eggs of Toxocara in human toxocariasis diagnosis is unreliable due to autofluorescence nature

Toxocariasis is caused by infection with the nematode species Toxocara canis and Toxocara cati. Serological methods using eggs, larvae and adult worms of Toxocara spp. as antigen have been used for the diagnosis of human toxocariasis. The current study aimed to evaluate indirect immunofluorescence assay (IFA) using embryonated eggs of Toxocara for diagnosis of human toxocariasis. A total of 58 sera including twenty sera from patients with toxocariasis, 20 from healthy persons and 18 from patients with other parasitic infections were collected and used for the study. The embryonated eggs of Toxocara were prepared as antigen. Indirect immunofluorescence assay was performed using the frozen section of uterus containing embryonated T. canis eggs and unembryonated T. cati eggs. All serum samples had a positive reaction using IFA. The eggs of Toxocara as antigen exposed to the serum samples of toxocariasis, other parasitic infections and healthy persons, followed by IFA gave a bright greenish-yellow fluorescence. A number of samples such as eggs of Toxocara, Toxascaris, Trichuris and strongyloides larvae, and adult worm of Ancylostoma exhibited the bright greenish-yellow autofluorescence under fluorescent microscope. IFA using cryocut of embryonated eggs of Toxocara cannot be used for the diagnosis of human toxocariasis due to the existence of autofluorescence of the unembryonated and embryonated eggs, the second stage larva and adult worms of Toxocara spp.

Helminth Infections in Children.

Helminth Infections in Children.

Human toxocariasis: A rare parasitosis (about 16 cases)

Toxocariasis is a helminthozoonosis with cosmopolitan distribution, due to the presence in the human body of larvae of a nematode of the genus Toxocara. (T.)Spp. Two nematodes are responsible for human toxocariasis: T. canis and T. catis. The objective of our study is to describe the epidemiological, clinical, diagnostic, therapeutic and evolutionary characteristics of human toxocariasis.