Prevalence of Toxocariasis and Its Risk Factors in Patients with Eosinophilia in Korea

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.

Toxocariasis: potential association with bronchial asthma, and pneumonia among pediatric children

Toxocariasis is an underestimated geohelminthic infection which shows respiratory changes concurrent with larval migration. The purpose of the present study was to detect Toxocara seropositivity in asthmatic and pneumonic children, and in turn to evaluate its association with the children clinical manifestations, laboratory test results, and sociodemographic risk factors. A total of 50 asthmatic, 50 pneumonic children and 50 healthy controls were subjected to stool analysis by direct wet mount and concentration techniques to exclude possible cross reactivity. Blood samples were collected for complete blood count and assessment of eosinophil count. Sera were examined for anti-Toxocara IgG antibodies, and measurement of total IgE level. Anti Toxocara IgG was detected in 27.3% (41/150) of the studied children. It was significantly higher in asthmatic group compared to controls (26%. p value = 0.033) and significantly highest in pneumonia group compared to both bronchial asthma group (46%. p value = 0.030) and control group (10%. p value = 0.001). There was a significant association between anti Toxocara IgG seroprevalence and each of eosinophilia, total IgE and both combined. Anti Toxocara IgG showed significant higher percentage in asthmatic children who recorded history of soil contact and pets contact as compared to control and pneumonic groups. Toxocara IgG seropositivity was highly associated with fever, cough, wheezes and dyspnea with statistical significance. Toxocara seropositivity has to be considered as a vital associated factor for asthmatic and pneumonic children, and eventually better to be considered in differential diagnosis by pediatricians. Further studies are still needed to explore the correlation between toxocariasis and different patient categories.

Seroprevalence of Toxocariasis Among Hypereosinophilic Children: A Single Center Study, Tehran, Iran

Background: Toxocariasis is a parasitic disease causing hypereosinophilia. This study aimed to investigate the serological prevalence of toxocariasis among hypereosinophilic children in Children’s Medical Center, Tehran, Iran, as well as to explore its relationship with epidemiological variables and some blood indices. Methods: This descriptive cross-sectional study was performed in 2020 on children referred to referral children hospital for routine tests. A total of 282 children diagnosed with hypereosinophilia were selected and included in the study, and then, their serum was collected. After obtaining informed consent from their parents, the parents were asked to fill out a questionnaire. The serological ELISA test was used to assess the anti-Toxocara IgG antibody. Data were analyzed using SPSS software 18. Results: Out of 282 hypereosinophilic children, 17 (6%) had serological results positive for anti-Toxocara antibody. The mean age of children with toxocariasis was higher than that of children without toxocariasis (P = 0.312). Furthermore, ESR and CRP variables were significantly higher in infected children than those in non-infected children (P < 0.05). Conclusions: The results of the present study confirmed the relationship between toxocariasis and hypereosinophilia. Since the symptoms of toxocariasis are non-specific and may go undiagnosed, it was found necessary to examine toxocariasis in cases of hypereosinophilic individuals.

Serosurvey of anti-Toxocara canis antibodies in people experiencing homelessness and shelter workers from São Paulo, Brazil

BACKGROUND

Despite being one of the most prevalent helminth parasitic zoonoses worldwide and particularly in socioeconomically vulnerable populations, toxocariasis remains to be fully investigated in persons experiencing homelessness. Accordingly, the present study has aimed to assess the seroprevalence and associated risk factors of Toxocara spp. exposure in persons experiencing homelessness and shelter workers from a day-shelter in São Paulo city, Brazil.

METHODS

Anti-Toxocara IgG antibodies were detected by enzyme-linked immunosorbent assay (ELISA). Univariable and multivariable logistic regression models were performed to assess the risks for toxocariasis.

RESULTS

Overall, anti-Toxocara IgG antibodies were detected in 89/194 (45.9%, 95% CI: 39.0-52.9%) persons experiencing homelessness, twice as high (OR = 2.2; 95% CI = 1.245-3.873; P = 0.0089) than the frequency of 22/79 (27.8%, 95% CI: 19.2-38.6) in shelter workers. College education was the only protective factor for Toxocara spp. exposure (OR: 0.23; P = 0.018) revealed by logistic regression.

CONCLUSIONS

Although indicating a multifactorial origin of toxocariasis, the present study has assessed a highly vulnerable population with high disease risks and premature death. Thus, the living conditions of the homeless population have influenced the high prevalence of anti-Toxocara antibodies verified here compared with domiciled shelter workers. Despite being less exposed, shelter and other outdoor workers may present an occupational risk to toxocariasis. Future studies should establish whether such environmental exposure might occur in persons experiencing homelessness in other regions worldwide.

Green vegetable juice as a potential source of human fascioliasis in Korea

Fascioliasis, a food-borne helminthiasis, is primarily a disease of cattle and sheep that occasionally occurs in humans. The aquatic perennial herb water dropwort (Oenanthe javanica) has been identified as the primary source of human infections in Korea. Recently, a cluster of patients who had not ingested water dropwort, but had the use of a green vegetable delivery service in common was diagnosed with fascioliasis. Our study aimed to identify the association between the green vegetable juice delivery service and the occurrence of human fascioliasis.

Patients with liver abscesses and eosinophilia were enrolled in this study. They were categorized into fascioliasis or non-fascioliasis groups according to serological test results, clinical manifestations, and computed tomography or magnetic resonance imaging findings. Patients were classified into the fascioliasis group when ova or the adult worms of the Fasciola species were detected or serological tests were positive, with compatible clinical and radiological findings.

We included 30 patients in this study; 15 were assigned to the fascioliasis group and the remaining 15 to the non-fascioliasis group. The proportion of patients who utilized the juice delivery service was significantly higher in the fascioliasis group than in the non-fascioliasis group (53.3% vs. 0%, P < 0.01). Most of the other patients in the fascioliasis group had known risk factors and the intake of water dropwort or other raw vegetables.

This study suggests that human fascioliasis could be transmitted by green vegetable juice produced and delivered by modern industrial systems. Further research on the product, industry and farm-level situations is required to validate these findings.

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Fresh-juices made from raw, unheated vegetables may carry microorganisms.

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The association between green juice consumption and human fascioliasis was studied.

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Exposures were evaluated for 30 patients with liver abscess and eosinophilia.

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More patients with fascioliasis used the green juice delivery than control group.

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The modernized green juice delivery service was associated with human fascioliasis.

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.

The Role of Nile Tilapia (Oreochromis niloticus) in the Life Cycle of Toxocara spp

The present study aimed to experimentally assess Nile tilapia as potential paratenic host of Toxocara spp. A total of 15 Nile tilapia (Oreochromis niloticus) were fed with 300 embryonated Toxocara canis eggs by oral gavage, while five others of the control group received distilled water. The fish were individually analyzed at 16, 24, 48, 72, and 240 h after inoculation. Water contamination was assessed, and tissue migration by liver, gastrointestinal tract (GIT), eyes, and central nervous system. A murine model was used as the paratenic host for egg infectivity assessment. Eggs and larvae were found in plastic tank water and fish GIT, ranging from 23 to 86% per fish. Eggs and larvae were recovered from the tank water (76.3%) and fish GIT (23.7%). The counting of eggs and larvae observed was negatively correlated with number of eggs and larvae in the water tank (rho = -0.698, p = 0.003). Shedding of embryonated eggs was first detected at 16 and up to 240 h, with significant egg and larvae yield decrease on water-shedding (p = 0.001) and in the GIT (p = 0.007). Although no T. canis larva was recovered in fish tissues, egg infectivity after fish GIT transit was experimentally confirmed by mice assessment. In conclusion, despite shedding viable embryonated eggs through the gastrointestinal tract, tilapias may not play a role as a suitable paratenic hosts for Toxocara spp., posing low risk of zoonotic transmission by fish meat consumption.

Toxocariasis-Associated Acute Perimyocarditis with Cardiogenic Shock: A Case Report

Patient: Female, 21-year-old

Final Diagnosis: Toxocariasis-associated acute perimyocarditis with cardiogenic shock

Symptoms: Dizziness • epigastric pain • headache • vomiting

Medication: —

Clinical Procedure: —

Specialty: Cardiology