Seroprevalence of human Toxocara infections in the Roma and non-Roma populations of Eastern Slovakia: a cross-sectional study

Prevalence of antibodies to Toxocara canis and its associated risk factors in socio-economically deprived nomadic communities of Pakistan

Toxocariasis is an important zoonotic disease caused by Toxocara (T.) canis with considerably higher prevalence in developing countries. The data on its epidemiology, especially in socioeconomically deprived nomadic communities, are scarce in Pakistan. Therefore, this study was conducted to determine the prevalence of anti-T. canis antibodies and its associated risk factors in nomadic communities located in and around Multan, Pakistan. A total of 184 sera samples were collected from nomadic communities by simple random sampling technique. The descriptive epidemiological data of participants were collected on well-designed questionnaires. Prior consent was also obtained from the participants to use the data generated from their samples without showing their identity. All the samples were analysed for the detection of anti-T. canis antibodies using commercially available Enzyme-Linked-Immunosorbent-Assay (ELISA) kits having 91% sensitivity and 96% specificity (Bordier Affinity Products, Switzerland). The overall seroprevalence of toxocariasis among nomadic communities was 27.7% (51/184). Various factors, including age, known disease history, nutritional status, contact with dogs, practice of hand washing after contact with dogs, use of unwashed vegetables, body mass index, and drug abuse, showed significant correlation (p < 0.05) with toxocariasis in nomadic communities. Conversely, other factors, including gender, marital status, educational status, awareness about zoonotic diseases, source of drinking water, occupation, location, hand washing before taking food, exposure to soil, and hygienic eating behaviour, showed non-significant correlation (p > 0.05) with seroprevalence of toxocariasis. Results also showed that >50% of seropositive cases were asymptomatic, whereas cough and abdominal pain were recorded in 19.6% and 11.76% of seropositive cases, respectively. Keeping in view, it is suggested to conduct surveys at mass level to rule out the exact disease status at national level and to include nomadic communities in local, national, and regional disease control programs through provision of better healthcare facilities and awareness about the disease.

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.

Parasitic zoonoses in the Roma population

Roma people are the largest minority group in Europe. The vast majority live in substandard conditions in segregated settlements, overcrowded with people and animals that predispose them to various, especially zoonotic diseases. Parasitic zoonotic diseases remain a challenge in this vulnerable population group, especially among Roma children. PubMed was searched using the keywords Roma with combination of names of different parasites to get all available studies on prevalence of parasitic zoonoses among European Roma, published between years 2000 and 2020. After application of exclusion criteria, data were extracted from the studies that made the final sample. Parasitic zoonoses are common among Roma. Cryptosporidium, Toxoplasma gondii, soil-transmitted helminths and Giardia spp. are more common in Roma children compared to non-Roma children, and Toxoplasma gondii and soil-transmitted helminths are also more common in Roma adults compared to non-Roma adults. Data on prevalence of trichinellosis, echinococcosis, and taeniasis among Roma show that they do not affect Roma more often compared to the general population. Roma people, particularly children, are more susceptible to parasitic zoonoses. Substandard sanitary conditions and close contact with infected animals are important risk factors in this population and should be aimed with preventive measures.

Roma Health: An Overview of Communicable Diseases in Eastern and Central Europe

The Roma are Europe’s largest minority. They are also one of its most disadvantaged, with low levels of education and health and high levels of poverty. Research on Roma health often reveals higher burdens of disease in the communities studied. This paper aims to review the literature on communicable diseases among Roma across Eastern and Central Europe. A PubMed search was carried out for communicable diseases among Roma in these parts of Europe, specifically in Romania, Bulgaria, Hungary, Serbia, Slovakia, the Czech Republic and North Macedonia. The papers were then screened for relevance and utility. Nineteen papers were selected for review; most of them from Slovakia. Roma continue to have a higher prevalence of communicable diseases and are at higher risk of infection than the majority populations of the countries they live in. Roma children in particular have a particularly high prevalence of parasitic disease. However, these differences in disease prevalence are not present across all diseases and all populations. For example, when Roma are compared to non-Roma living in close proximity to them, these differences are often no longer significant.

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 and incidence of human toxocarosis in Russia

Overall incidence of toxocariasis in Russia is low and varies between 1.6 and 2.7 per 100,000, while in several hyper-endemic regions, such as Altay, Kurgan, Perm and Udmurtia, it reaches 43 per 100,000. The seroprevalence of toxocariasis in published references was on average 16% and varied across the regions of Russia from negligible in North Siberia to 40% in southern regions of West Siberia. Seroprevalence in adults in five regions of Russia identified in this study was on average 20%, and varied from 3% in Yakutia (north of East Siberia) to 36% in Rostov-on-Don, South Russia. There was no correlation between seroprevalence and reported incidence of toxocariasis; however, the pattern of seroprevalence variation could be linked to Toxocara prevalence in dogs. Toxocariasis seroprevalence has more than doubled over the last 20 years. Diagnostic antibody titres (1:800 or more) were found in 3.6% of sera, suggesting about five million of acute Toxocara invasions per year.

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.

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.

Seroprevalence of Larval Toxocarosis in the Czech Republic

BACKGROUND

Larval toxocarosis (LT), a zoonotic disease transmitted by dogs, cats, and other carnivores, is caused by roundworms of the genus Toxocara. Humans become infected by ingesting embryonated eggs of this parasite. In this study, we present data on the seroprevalence of LT in the Czech Republic collected by the National Reference Laboratory for Tissue Helminthoses in 2012-2016.

METHODS

Using enzyme-linked immunosorbent assay, a total of 4428 adults and children with or without clinical symptoms were examined for the presence of IgG antibodies against Toxocara canis excretory-secretory antigens.

RESULTS

Of all the persons examined, specific Toxocara antibodies were detected in 160 (3.6%) individuals. There were, however, significant differences between various regions, with seropositivity rates ranging from 1.4 to 7.5%.

CONCLUSION

In comparison to studies from 1998 and 2004, our results suggest a decrease in overall Toxocara seroprevalence in the Czech population, whereby the rates are similar to or even lower than rates in some other Central European countries.

Is the Definition of Roma an Important Matter? The Parallel Application of Self and External Classification of Ethnicity in a Population-Based Health Interview Survey

The Roma population is typified by a poor and, due to difficulties in ethnicity assessment, poorly documented health status. We aimed to compare the usefulness of self-reporting and observer-reporting in Roma classification for surveys investigating differences between Roma and non-Roma populations. Both self-reporting and observer-reporting of Roma ethnicity were applied in a population-based health interview survey. A questionnaire was completed by 1849 people aged 18–64 years; this questionnaire provided information on 52 indicators (morbidity, functionality, lifestyle, social capital, accidents, healthcare use) indicators. Multivariate logistic regression models controlling for age, sex, education and employment were used to produce indicators for differences between the self-reported Roma (N = 124) and non-Roma (N = 1725) populations, as well as between observer-reported Roma (N = 179) and non-Roma populations (N = 1670). Differences between interviewer-reported and self-reported individuals of Roma ethnicity in statistical inferences were observed for only seven indicators. The self-reporting approach was more sensitive for two indicators, and the observer-reported assessment for five indicators. Based on our results, the self-reported identity can be considered as a useful approach, and the application of observer-reporting cannot considerably increase the usefulness of a survey, because the differences between Roma and non-Roma individuals are much bigger than the differences between indicators produced by self-reported or observer-reported data on individuals of Roma ethnicity.

A Community-Based Study to Estimate the Seroprevalence of Trichinellosis and Echinococcosis in the Roma and Non-Roma Population of Slovakia

Trichinellosis and cystic and alveolar echinococcosis are serious parasitic diseases transmissible between animals and humans. Moreover, alveolar echinococcosis is considered one of the most dangerous of human helminthoses. Roma communities are particularly numerous in Central and Eastern Europe. They are often concentrated in economically undeveloped regions and live in segregated localities with unsatisfactory housing and sanitary conditions. The study aimed to find out the seroprevalence of Trichinella and Echinococcus infections in the Roma population of segregated settlements and to compare it with the seropositivity of the non-Roma population of eastern Slovakia. Out of 823 samples, three sera showed seropositivity to Trichinella in the ELISA (Enzyme-linked immunosorbent assay) test. Subsequent Western blot reaction (WB) confirmed seropositivity in two Roma women. ELISA seropositivity to E. multilocularis was recorded in six persons (0.73%), and five (0.61%) respondents were seropositive to E. granulosus, but WB confirmed the presence of antibodies to Echinococcus spp. in one Roma participant. Positive persons suffered from unspecific clinical symptoms; Trichinella-positive persons reported headache, cough, fatigue, and muscle pain. The Echinococcus-positive participant suffered from headache and back pain. The study showed that the worse living conditions of the Roma community did not significantly influence the occurrence of Trichinella and Echinococcus infections in this minority.

Assessment of the diagnostic value of specific anti-Toxocara IgA in Slovakian patients suspected to have toxocarosis

Human toxocarosis is one of the most widespread and prevalent helminthic zoonosis in many countries, including Slovakia. The aim was to evaluate the usefulness of IgA anti-Toxocara antibody detection in the serodiagnosis of toxocarosis. The levels of specific IgA antibodies were determined by excretory-secretory (ES)-enzyme-linked immunosorbent assay (ELISA). The IgA seropositivity in IgG anti-Toxocara seropositive patients (n = 52) was 32.7% and found to be highest in the oldest age groups (P = 0.026). The presence of IgA in suspected patients for toxocarosis were evaluated in respect to some characteristics of examined persons. Substantially higher IgA seropositivity was detected in patients with increased total IgE (44.8%) than in subjects with a normal level of IgE (17.4%; P = 0.036). No associations (P > 0.05) were found between IgA seropositivity and sex, level of specific IgG antibodies, avidity of IgG, eosinophilia, domicile, geophagia, traveling abroad, dog/cat ownership, or clinical symptoms. The IgA-ELISA showed sensitivity of 57.1% and specificity of 100%. Mild correlations (r = 0.302, r = 0.305, r = - 0.409) were observed between the levels of anti-Toxocara IgA antibodies and age, the amounts of eosinophils and IgA antibody levels, the amounts of eosinophils, and the values of IgG avidity, respectively. The presence of anti-Toxocara IgA may facilitate the diagnosis of toxocarosis and may well be useful for the determination of acute Toxocara infection. Moreover, this test should be accompanied by other immunological markers of examined patients (e.g., increased total IgE, eosinophilia, and low-avidity IgG antibodies).

Segregated settlements present an increased risk for the parasite infections spread in Northeastern Slovakia

The occurrence of parasitic infections among the children, dogs and its association with soil contamination in two villages with different hygiene level standards were analysed. Infections were present in both examined localities, but in the village with higher living standard, a better personal and communal hygiene level and better dogs care a lower occurrence of parasitic germs in soil was detected. High prevalence of protozoa and helminths was observed not only within canine population but also in children throughout the year in the village with lower hygiene and socio-economic standard. We have identified up to 12 taxa of parasites in 127 collected dogs’ excrements and mean prevalence was 71.65 %. The most frequent were eggs of family Ancylostomatidae and Ascaris spp., followed by Toxocara canis, Toxascaris leonina, Giardia duodenalis cysts, Isospora spp. oocysts, eggs of Capillaria aerophila, Trichuris vulpis, Taenia type eggs, Dipylidium caninum, oocysts of Sarcocystis spp. and larvae of Angiostrongylus vasorum. The soil samples collected near dwellings were highly contaminated. Two thirds of samples contained eggs for the most part of family Ancylostomatidae as well as genera Ascaris and Toxocara. Among the kids population helminth ova were present in 53.17 % of stool samples, where the eggs of Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis, Hymenolepis diminuta and cysts of G. duodenalis were the most frequent. In contrast, parasitic diseases were not seen in children population living in the locality with common hygiene standard.

Seroprevalence and associated risk factors of Toxocara infection in Korean, Manchu, Mongol, and Han ethnic groups in northern China

Toxocariasis is a very prevalent zoonotic disease worldwide. Recently, investigators have focused more on Toxocara spp. seroprevalence in humans. Information regarding Toxocara seroprevalence in people from different ethnic backgrounds in China is limited. For this study, blood samples were collected from a total of 802 Han, 520 Korean, 303 Manchu, and 217 Mongol subjects from Jilin and Shandong provinces. The overall Toxocara seroprevalence was 16·07% (14·21% Han, 20·58% Korean, 11·22% Manchu, 18·89% Mongol). Living in suburban or rural areas, having dogs at home, exposure to soil, and consumption of raw/undercooked meat were risk factors for Toxocara infection. Exposure to soil was identified as the major risk factor for Toxocara seropositivity in all of the tested ethnicities. To the best of our knowledge, this is the first report concerning Toxocara infection in Manchus and Mongols in China. The present study provided baseline data for effective prevention strategies of toxocariasis in northeast China and recommends improvements in personal hygiene standards to achieve this goal.

Parasitic Zoonoses in Humans and Their Dogs from a Rural Community of Tropical Mexico

A cross-sectional study was made on 89 inhabitants and their dogs from a rural community of Yucatan, Mexico, to determine the serological prevalence of some zoonotic parasitic agents. Samples were taken to monitor the presence and intensity of infection with gastrointestinal parasites in dogs. In humans, the serological prevalence of T. canis, T. gondii, and T. spiralis was 29.2%, 91.0%, and 6.7%, respectively. No associations were found between positive cases and studied variables. From the total of blood samples taken from dogs, 87 (97.6%) were seropositive to T. gondii; only 52 viable fecal samples were collected from dogs of which 46.2% had the presence of gastrointestinal parasites with low to moderate intensity; from those, 12% had the presence of T. canis. This study demonstrates the presence of the studied zoonotic agents in the area particularly T. gondii which suggest a common source of infection in dogs and humans and a high number of oocyts present in the environment. Preventive measures must be designed towards good prophylactic practices in domestic and backyard animals (T. canis and T. spiralis). Contaminated sources with T. gondii (food and water) should be further investigated in order to design effective control measures.