Seroprevalence and Potential Risk Factors of Toxocariasis among General Population in Southwest Iran: Implications on the One Health Approach.

Toxocariasis is one of the most common zoonotic diseases distributed worldwide. This study aimed to estimate the seroprevalence of anti-Toxocara immunoglobulin G (IgG) antibodies and the associated risk factors among general populations living in urban and rural areas of Abadan and Khorramshahr cities in Khuzestan Province, Southwest Iran. This cross-sectional study was conducted between March and September 2022. There were 363 participants (190 females and 173 males) aged from <20 to ≥60 years old. Anti-Toxocara IgG antibodies in serum samples were measured using a commercially available enzyme-linked immunosorbent assay (ELISA). A structured questionnaire was employed to collect information regarding sociodemographic status and probable risk factors associated with toxocariasis. It was found that the seroprevalence rate in males (15.0%, 95% CI = 10.47-21.11) was higher than in females (10.5%, 95% CI = 6.92-15.70). Moreover, we observed that the seroprevalence was higher in participants at younger ages compared to other age ranges (COR = 2.55, 95% CI = 0.92-7.12, p =0.073). The findings of the univariate analysis revealed that residency in rural areas (p < 0.001), using unpurified water (p < 0.001), contact with dog (p =0.002), contact with soil (p < 0.001), consumption of improperly washed vegetables (p < 0.001), and history of drinking untreated water (p < 0.001) were risk factors associated with toxocariasis. Further comprehensive studies with a focus on humans and animals should be designed in different areas of the Province. The data represented by the current study are useful to health policymakers to consider precise surveillance and effective prevention measures to control this zoonotic infection among general populations.

Seroprevalence of Toxocara at Tra Vinh University Hospital in Vietnam.

OBJECTIVE: The study aims to assess the seroprevalence of Toxocariasis and its associated risk factors among individuals attending the outpatient department at Tra Vinh University Hospital, Vietnam, in 2022. SUBJECTS AND METHODS: A cross-sectional survey was conducted among outpatients of Tra Vinh University Hospital. Toxocariasis diagnosis was based on the Enzyme-Linked Immunosorbent Assay (ELISA) performed at the hospital's laboratory department. We assessed the seroprevalence of Toxocariasis and evaluated associated risk factors, including demographics and certain behaviors. RESULTS: Of the 249 participants surveyed, 165 tested positive for Toxocariasis, yielding a seroprevalence of 66.3% (95% CI: 60.4-72.1). Multivariate analysis revealed that age groups up to 30 and 30-60 years had higher odds of Toxocariasis infection, with adjusted odds ratios (aOR) of 2.52 (95% CI: 1.04-6.11) and 3.21 (95% CI: 1.44-7.15) respectively. Additionally, individuals residing in rural areas and those in contact with dogs or cats had increased risks, with aORs of 2.21 (95% CI: 1.21-4.01) and 2.04 (95% CI: 1.10-3.79), respectively. Notably, hand washing before eating emerged as a protective factor against Toxocariasis, presenting an aOR of 0.38 (95% CI: 0.19-0.76). CONCLUSIONS: Our findings underscore a significant seroprevalence (66.3%) of Toxocara spp. among outpatients at Tra Vinh University Hospital. Proactive measures, including hand hygiene before meals and after pet interactions, are advocated. There is a pronounced need for community-level epidemiological surveillance for human Toxocariasis.

Sources and seroprevalence of toxocariasis in Turkey.

Toxocariasis in humans is considered a rare disease in Turkey, and the absence of specific symptoms of this disease is probably the main reason for clinicians to underestimate and underdiagnose the disease. Although there are several seroepidemiological studies on visceral larva migrans in the country, a comparison between them is difficult as the serological tests are not standardised. After the introduction of the easily accessible ELISA kit in the market, the number of seroepidemiological studies has increased in which the reported rates ranged between 1% and 56%. Similar to other countries, Toxocara seropositivity in Turkey is more common in men, childhood, in those living in rural area, having a low income level, owning dogs, and biting their nails or practicing geophagia. In addition, toxocariasis is a risk factor for veterinarians, farmers, and pet-shop workers. Toxocara seroprevalence is significantly higher in respiratory, neuropsychiatric, musculoskeletal, skin and abdominal disorders. There are also many studies showing the importance of eosinophilia in toxocariasis. In conclusion, although there are many studies on toxocariasis in Turkey, it is still not well understood to what extent the infection is responsible for a plethora ascribed symptoms. Standardisation of the diagnostic methods and the use of molecular techniques could further throw light in the real epidemiology and the role played by the infection to induce signs and symptoms.

Seroprevalence of Toxocara spp. antibodies in humans in Africa: A review.

BACKGROUND: Human toxocariasis occurs worldwide and is caused by nematodes of the species of the genus Toxocara. Infection occurs by the ingestion of eggs and is usually asymptomatic or oligosymptomatic. However, severe manifestations occur. The burden of disease and its public health impact remain ill-defined. The aim of this review was to summarize all available data on the seroprevalence of toxocariasis on the African continent and factors associated with seropositivity. METHODS: Twenty-seven original papers published between 1991 and 2017 were identified that provided data suitable for this review. Case-control studies were included and the seroprevalence in the (healthy) control group was used as a surrogate parameter. RESULTS: Antibodies against Toxocara spp. were found to be frequent in most populations and regions in Africa with the exception of two publications, one from the Democratic Republic of the Congo and one from Djibouti, where all participants were seronegative. The highest proportion of participants with antibodies was found on the island of La Réunion with 359 out 387 study participants being positive (92.8%). Factors associated with seropositivity were reported across studies, including-among others-older age, contact with soil via geophagia, agricultural activity or playing with soil, contact with animals, especially dogs, and low socio-economic status, defined as absence of water supply or poor housing. Three Egyptian studies found male gender to be associated with toxocariasis, whereas in La Réunion females were at increased risk. CONCLUSIONS: Exposure to toxocariasis seems to be very frequent and common in large parts of the African continent. However, no data are available for most countries. The public health impact of human toxocariasis and the frequency of severe manifestations remain unclear.

Seroepidemiology of human toxocariasis in North Africa.

Seroprevalence studies on human toxocariasis help to assess the burden and the morbidity associated with this zoonosis. This review searched the seroprevalence studies and case reports in six North African countries: Algeria, Egypt, Libya, Morocco, Sudan and Tunisia, since 1990. The search also included studies on the environmental factors related to the risk of transmission. Most of the published epidemiological studies were done in Egypt. Cross-sectional and case-control studies in Egypt demonstrated that toxocariasis is a significant zoonosis that could be associated with conditions like bronchial asthma allergies and certain neuropsychiatric disorders. The population at risk of this infection includes all ages, both genders, in contact with dogs, resident in rural areas with poor housing conditions. The publications from Tunisia, Morocco and Algeria are limited to case reports and retrospective analyses of cases, but the disease is probably under-diagnosed in these three countries. There are no published reports on human toxocariasis in Libya and Sudan during the period covered by the review. Animal studies confirm high infection rates of dogs with Toxocara canis in North Africa. There is also evidence of wide-spread contamination of soil and water with Toxocara spp. eggs. Moreover, the use of untreated wastewater for irrigation in parts of North Africa could be a source of contamination of agricultural products with eggs of Toxocara spp. Population-based studies on human toxocariasis are recommended, using standardized diagnostic tests. These surveys should also assess risk factors to guide preventive measures.

Sources of environmental contamination with Toxocara spp.: An omnipresent parasite.

Embryonated Toxocara eggs in the environment are considered to be the most important source of human toxocariasis. These eggs, however, are also a source of infection for the definitive and paratenic hosts. Most available literature focuses on Toxocara canis in dogs, or other canids. There are, however, other Toxocara species with their accompanying definitive hosts. Results from studies that modelled patent infections in dogs, cats and foxes show that although dogs are a very important source for environmental contamination with Toxocara eggs, other sources cannot be ignored. For a good understanding of the relative contributions of different definitive hosts to environmental contamination with Toxocara eggs, computational models should be built and fed with data from different fields of expertise as is discussed in this paper.

Toxocara prevalence in dogs and cats in Brazil.

I herein review published studies reporting the prevalence of Toxocara infection in dogs and cats in Brazil. Based on data gathered from faecal examinations of approximately 38,940 dogs and 5600 cats from different Brazilian studies, the mean prevalence of Toxocara infection is 11.4% (range: 0.7-48.9%) in dogs and 16.7% (0.3-43.1%) in cats. These mean values based on faecal examinations should be interpreted with cautious, considering the obvious differences in terms of sample size, diagnostic tests and animal populations. Accordingly, necropsy investigations reveal higher mean prevalence values (21.9% for Toxocara canis and 27.6% Toxocara cati in dogs and cats, respectively). The contamination with Toxocara eggs in different environments and the significance of these parasites from a public health perspective in Brazil are briefly discussed.

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.

Epidemiology of Toxocara spp. in dogs and cats in mainland China, 2000-2019.

Toxocariasis is a neglected parasitic zoonosis. Although some studies have reported the Toxocara prevalence in dogs and cats in mainland China, there is a lack of comprehensive analysis of these data. Here, we conducted the first systematic review based on relevant literatures published in Web of Science, PubMed and CNKI from January 2000 to July 2019 to assess the prevalence of Toxocara infection in dogs and cats in mainland China. A total of 68 eligible papers were retrieved, including 24,490 dogs and 844 cats, with 17.34% (4246/24,490) Toxocara canis prevalence in dogs and 22.04% (186/844) Toxocara cati prevalence in cats by faecal floatation method. The prevalence and risk factors of T. canis and T. cati infection in different geographical regions, years, breeds, ages and genders were estimated in this review. This review indicates that there was high prevalence of Toxocara infection in dogs and cats in China. This finding calls for measures to reduce the potential risk of Toxocara infection and toxocariasis in humans and animals.

Prevalence of Toxocara in dogs and cats in Africa.

Dogs and cats have a close association with humans providing companionship; however, pets are reservoirs of zoonotic pathogens such as Toxocara. Toxocara canis and Toxocara cati are small intestinal nematodes found in canids and felids, respectively. Infected pets shed thousands of eggs resulting in environmental contamination. Toxocara can infect a wide variety of paratenic hosts including humans, rodents, pigs and chickens. Paratenic hosts become infected by ingestion of the infective eggs containing the third stage larvae or ingestion of dormant larvae in animal tissues. Infected humans may develop visceral larval migrans or ocular toxocariasis. Regular anthelmintic treatment and restricted movement of dogs and cats are recommended to control Toxocara environmental contamination. This paper reviews the prevalence and risk factors of Toxocara in dogs and cats in Africa; and pet owners' awareness of canine zoonotic helminths.

Prevalence of toxocariasis and its related risk factors in humans, dogs and cats in northeastern Iran: a population-based study.

BACKGROUND: Toxocariasis is one of the most common zoonotic infections in dogs and cats. The objectives of this study were to determine the prevalence of anti-Toxocara antibodies and identify the epidemiological and clinical features and related risk factors of toxocariasis in the general population along with the prevalence of this infection in dogs and cats in northeast Iran. METHODS: In this cross-sectional study, anti-Toxocara antibodies from 1150 urban and rural participants were examined using a commercial enzyme-linked immunosorbent assay. In addition, the stool specimens of 538 dogs and 236 cats were tested using the formalin-ether concentration technique. Sociodemographic data and related risk factors were collected using a structured questionnaire and the data on clinical manifestations were obtained from personal health records. RESULTS: Anti-Toxocara antibodies were detected in 7.2% (83/1150) of the study population. Risk factors for seropositivity based on multivariable analysis were younger age (p=0.019), living in rural areas (p=0.048), occupations with high exposure risk to toxocariasis (p=0.001), contact with dogs or cats (p=0.003), contact with soil (p=0.001), history of geophagy (p=0.001) and the consumption of raw or undercooked liver (p=0.001). The prevalence of symptoms such as asthma, shortness of breath, blurred vision, abdominal pain and epilepsy were significantly higher in seropositive individuals compared with seronegative ones. Toxocara eggs were found in 15.1% (81/538) of dogs and 34.7% (82/236) of cats. A significant relationship was found between infection in dogs and cats and age, type, place of residence and anthelmintic consumption. CONCLUSIONS: Identification of anti-Toxocara antibodies in the general population and the presence of confirmed infections in dogs and cats indicates exposure to Toxocara infection as a public health problem in northeast Iran.

Seroepidemiology, modifiable risk factors and clinical symptoms of Toxocara spp. infection in northern Iran.

Toxocariasis is one of the most important and widespread neglected tropical infectious diseases. We designed a cross-sectional study to assess the seroepidemiological aspects of toxocariasis among the general population in northern Iran. A total of 630 rural subjects were enrolled to participate in the study. The presence of anti-Toxocara immunoglobulin G (IgG) was tested using a commercially available enzyme-linked immunosorbent assay. A structured questionnaire was also used to evaluate the potential risk factors and related clinical signs/symptoms. The presence of anti-Toxocara IgG antibodies was detected in 148 of the 630 rural subjects (23.5% [95% confidence interval {CI} 21.8 to 25.1]). By multivariate analysis, age (odds ratio [OR] 2.89 [95% CI 1 to -8.3], p=0.04), eating improperly washed vegetables (OR 4.05 [95% CI 2.47 to 6.64], p<0.001), contact with dogs (OR 3.31 [95% CI 2.13 to 5.12], p<0.001) and exposure to soil (OR 3.56 [95% CI 2.13 to 5.13], p<0.001) were significantly associated with the seroprevalence of Toxocara. The clinical study also demonstrated that the seroprevalence of Toxocara infection was significantly associated with asthma (OR 3.78 [95% CI 1.63 to 8.75], p<0.001) and ophthalmic disorder (OR 1.83 [95% CI 1.04 to 3.21], p=0.034). The findings proved that residents of rural communities in tropical regions may be heavily exposed to Toxocara spp. We highly recommend more investigations in high-risk groups.

Toxocariasis ocular. A propósito de un caso / Ocular toxocariasis. Case report

RESUMEN Se presentó un caso clínico de un paciente de seis años de edad, con toxocariasis ocular. La manifestación clínica fue disminución de la agudeza visual monocular. El fondo de ojo izquierdo mostró un granuloma retiniano periférico, asociado a un desgarro retiniano perilesional. El examen oftalmológico confirmó el diagnóstico de Toxocara ocular. El paciente fue tratado posteriormente mediante corticoides sistémicos y fotocoagulación láser focal en el desgarro retiniano (AU).

ABSTRACT We present the clinical case of a male patient, aged 6 years, with ocular toxocariasis. The clinical manifestation was monocular visual acuity decrease. The left ocular fundus showed a peripheral retina granuloma, associated to a perilesional retinal tear. The ophthalmological examination confirmed the diagnosis of ocular Toxocara. After that the patient was treated using systemic corticoids and focal laser coagulation in the retinal tear (AU).

Toxocariasis ocular. A propósito de un caso / Ocular toxocariasis. Case report

RESUMEN Se presentó un caso clínico de un paciente de seis años de edad, con toxocariasis ocular. La manifestación clínica fue disminución de la agudeza visual monocular. El fondo de ojo izquierdo mostró un granuloma retiniano periférico, asociado a un desgarro retiniano perilesional. El examen oftalmológico confirmó el diagnóstico de Toxocara ocular. El paciente fue tratado posteriormente mediante corticoides sistémicos y fotocoagulación láser focal en el desgarro retiniano (AU).

ABSTRACT We present the clinical case of a male patient, aged 6 years, with ocular toxocariasis. The clinical manifestation was monocular visual acuity decrease. The left ocular fundus showed a peripheral retina granuloma, associated to a perilesional retinal tear. The ophthalmological examination confirmed the diagnosis of ocular Toxocara. After that the patient was treated using systemic corticoids and focal laser coagulation in the retinal tear (AU).

Association between intermediate uveitis and toxocariasis in the Korean population.

The aim of the study was to investigate the characteristics of ocular toxocariasis (OT) presenting with intermediate uveitis in the Korean population.We studied intermediate uveitis patients using ocular and systemic evaluations and a Toxocara IgG serology test.Of 50 intermediate uveitis patients, 19 were seropositive for Toxocara IgG. Of the 19 OT patients, 4 presented with recurrence within 6 months and were significantly younger than nonrecurrence patients (P = 0.009). Thirteen patients had a history of eating raw cow liver.There were 14 males and 5 females in the OT group, and 11 males and 20 females in the non-OT group (P = 0.009). There was bilateral involvement in 7 out of 19 patients in the OT group, and 20 out of 31 patients in non-OT group (P = 0.033).Intermediate uveitis patients in OT were predominately male and had more unilateral presentation than non-OT patients.

[Ocular toxocariasis in a boy with idiopathic nephrotic syndrome - a case report]. / Toksokaroza oczna u chlopca z idiopatycznym zespolem nerczycowym ­ opis przypadku.

Toxocariasis is a common zoonosis caused by infection with Toxocara canis or cati larvae. Ocular toxocariasis is one of the forms of infestation found in 1/1,000 - 1/10,000 children. Children with idiopathic nephrotic syndrome (INS) are at high risk of infections, also parasitic infestations, which can, in turn, cause relapses of the disease. A CASE REPORT: We present a case of a 6-year-old boy with steroiddependent nephrotic syndrome. The disease started at age of 2, the boy had 9 relapses of INS, and was treated with oral prednisone, levamisole, and cyclophosphamide. During hospitalization with Xth relapse of INS, he was screened for causes of recurrences and IgG antibodies against Toxocara were found. Fundoscopy revealed white, slightly elevated, and discoloured inflammatory lesions in right retina without inflammation in the vitreous. Ocular toxocariasis was diagnosed. The boy was treated for 7 days with albendazole in the dose of 15 mg/kg/24 h with simultaneous increase of the dose of prednisone to 1mg/kg/24 h. In control fundoscopic examinations there was no progression of ocular lesions. CONCLUSIONS: In children on immunosuppressive treatment with possible exposure to animals or raw meet it is advisable to take serological tests for Toxocara infestation also in the absence of clinical symptoms of parasitic infection.

Seroprevalence and risk factors of Toxocara infection among children in Shandong and Jilin provinces, China.

This cross-sectional study was aimed to investigate the Toxocara serology in children in Shandong and Jilin provinces, China using an enzyme-linked immunosorbent assay (ELISA). The overall Toxocara seroprevalence among the study population (n=1458) was 19.3%, sick children (26.4%) had significantly higher seroprevalence than clinically healthy children (14.4%) (P<0.05), and the highest Toxocara seroprevalence was found in children suffering from chronic cough (40.6%), followed by recurrent abdominal pain (40.0%), recurrent headache (38.1%), slight fever (36.2%), and recurrent vomiting (31.6%). Place of residence, education level, type of school, keeping dogs at home, contact with dogs and cats and exposure with soil were found to be associated with Toxocara infection. Our findings show that children infection with Toxocara is common in Shandong and Jilin provinces, eastern and northeastern China, indicating an immediate need for implementing strategies and measures to prevent and control Toxocara infection in children in China.

Ocular toxocariasis.

Ocular toxocariasis is an uncommon worldwide parasitic infection that affects mostly children and is found in both rural and metropolitan areas. In many parts of the world, parasitic infections of the eye are a major cause of blindness. The diagnosis of toxocariasis is essentially clinical, based on the lesion morphology and supportive laboratory data such as serum enzyme-linked immunosorbent assay (ELISA) titers and ELISA Toxocara titers on aqueous humor; other diagnostic methods are imaging studies including optical coherence tomography, fluorescein angiography, computed tomography, and ocular ultrasound. Treatment is directed at complications arising from intraocular inflammation and vitreous membrane traction. Early vitrectomy may be of value both diagnostically and therapeutically.

[Investigation of anti-Toxocara canis IgG antibodies in patients presenting at The Erciyes University Medical Faculty, Department of Parasitology.]. / Erciyes Universitesi Tip Fakültesi Parazitoloji Anabilim Dali'na Müracaat Edenlerde Anti-Toxocara canis IgG Antikorlarinin Arastirilmasi.

Human Toxocara canis infections are seen all over the world, especially in temperate and tropical climate regions. Dogs are known to be reservoir hosts in transmission of the disease. Because puppies are infected both transplacentally and by breast milk, they add huge amounts of eggs daily to the environment with their stools for months. It is known that the human is not a natural host of T. canis and larvae do not mature in the human body. However, after getting into the human they migrate through visceral tissues and act like a foreign body in the places where they come to rest. In this study, anti-T. canis IgG antibodies were investigated by ELISA in 61 (54.6%) males and 51 (45.5%) females making a total of 112 patients aged between 1 and 68 years (average:18.54+/-24.5) presenting at our laboratory from different services of our hospital. Anti T. canis IgG antibodies were found to be positive in 24 (21.4%) patients.

National seroprevalence and risk factors for Zoonotic Toxocara spp. infection.

To estimate the prevalence of Toxocara spp. infection in a representative sample of the United States population >or= 6 years of age, sera from participants in the Third National Health and Nutrition Examination Survey (1988-1994) were tested for antibodies to Toxocara. Among the 30,930 persons selected for the survey, 82% (N = 25,733) were interviewed, and 91% (N = 23,527) of those interviewed underwent physical examination of which 87% (N = 20,395) were tested. The age adjusted Toxocara seroprevalence was 13.9% (95% confidence intervals [CI] 12.5, 15.3), and was higher in non-Hispanic blacks (21.2%) than non-Hispanic whites (12%) or Mexican Americans (10.7%; P < 0.001). Increased Toxocara seropositivity was associated with head of household level of education (low versus high) (odds ratio [OR]: 2.2; CI: 1.8, 2.8), poverty (OR: 1.5; CI: 1.3, 1.8), elevated blood lead concentrations (OR: 1.4; CI: 1.1, 1.9), and dog ownership (OR: 1.2; CI: 1.1, 1.4). Toxocara infection is widespread and associated with specific risk groups.