Seroprevalence of Toxoplasma gondii antibodies and associated risk factors among children in Shandong and Jilin provinces, China

Seroprevalence and Genetic Characterization of Toxoplasma gondii among Children with Neurodevelopmental Disorders in Egypt

Toxoplasma gondii is a parasite with a special predilection for the central nervous system. Toxoplasmosis's contribution to the triggering of many neurodevelopmental disorders was established. This study aimed to detect the seroprevalence and genotypes of T. gondii strains in children with neurodevelopmental disorders. The study included 180 children with neurodevelopmental disorders and 180 children in the control group. Assessment of seropositivity of Toxoplasma IgM and IgG antibodies in patients and controls was carried out. Genetic characterization of T. gondii was obtained by nested polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) technique targeting dense granule gene (GRA6). Our results showed that the overall seroprevalence of T. gondii antibodies in the patient and controls was 35.6% and 11.7%, respectively. Nested PCR showed positivity in 11.1% of the patient group for T. gondii DNA. T. gondii seropositivity rate was significantly high in patients with hydrocephalus and also in patients with epilepsy. Positive nested PCR was significantly high in children with hydrocephalus only. Genotyping using nested PCR-RFLP showed genotype I (80%) followed by atypical strains (20%) with no association with any specific clinical presentation. In conclusion, among toxoplasmosis-positive children with neurodevelopmental disorders, analysis of T. gondii GRA6 locus revealed the predominance of type I genotype followed by atypical strains.

Toxoplasma gondii Seropositivity and Associated Risk Factors in Cats (Felis catus) in Three Provinces in Northeastern China from 2013 to 2019

Toxoplasma gondii is an important protozoan parasite that can infect a range of animals. Cats are the most important definitive hosts for T. gondii. Therefore, an assessment of the level of T. gondii infection in cats is of public health importance. As limited information about seroprevalence of T. gondii infection in cats in northeastern China was available, 854 serum samples, including 235 cats in Jilin province, 267 cats in Liaoning province, and 352 cats in Heilongjiang province, were examined by an indirect hemagglutination assay (IHA) test, between September 2013 and July 2019. The overall seroprevalence of T. gondii was 19.09% (163/854) at the cutoff 1:64, with 19.60% (69/352), 18.29% (43/235), and 19.10% (51/267) in Heilongjiang, Jilin and Liaoning, respectively. Logistic regression analysis showed that mode of life was highly related to T. gondii infection in cats at the investigation areas. These results could provide foundation data for prevention and control of T. gondii prevalence in these regions. Moreover, the results also suggested that the effective control strategies should continue to be performed.

Seroprevalence and risk factors of Toxoplasma gondii infection in primary school children in Henan province, central China

Toxoplasma gondii is an obligate intracellular protozoan parasite with global distribution. However, data on T. gondii infection among children in primary school in Henan province, central China were lacking. In this study, 2451 serum samples of primary school children in this province were collected from September 2015 to October 2018 and evaluated for T. gondii antibodies using an enzyme-linked immunosorbent assay (ELISA). The overall seroprevalence was 9.51% (233/2451), of which 7.59% (186/2451) showed IgG positivity, 0.73% (18/2451) IgM and 1.18% (29/2451) both. The main risk factors related to T. gondii infections were the age of children, residence area, contact with cats, and exposure to soil. Moreover, hand washing before eating was considered a protective factor. Seroprevalence of T. gondii infection among the study population was common, emphasizing the need to prevent and control this infection. This is the first report of T. gondii seroprevalence in primary school children in Henan province, central China.

Toxoplasma gondii: seroprevalence and associated risk factors among preschool-aged children in Osun State, Nigeria

Background

Toxoplasma gondii is an ubiquitous apicomplexan parasite, which causes toxoplasmosis in animals and humans worldwide. However, little is known about T. gondii infection among preschool-aged children in Nigeria.

Methods

A cross-sectional study of 272 preschool children aged 2.25±1.09 years from four communities (Edunabon, Erin-Ijesha, Ijebu-jesa and Ile-Ife) in Osun State, Nigeria was conducted between January and July 2016, and the demographic data was obtained via questionnaires. Antibody titres against T. gondii of serum samples were assessed by ELISA.

Results

The overall seroprevalence of T. gondii infection was 6.9% (19/272). There was no significant difference in seroprevalence of T. gondii infection between boys (7.04%; 10/142) and girls (6.92%; 9/130; p=0.97). No associations were found between age, gender, parental educational level, occupation and religion, and T. gondii seropositivity. None showed statistical significance between the risk factors tested after multivariate adjustment; nevertheless, residing in Ijebu-jesa community was shown to be associated with an increased risk of infection (p=0.04).

Conclusion

This is the first report of T. gondii infection among preschool children in Nigeria. Prevalence studies such as this could help in the development of strategies for the future for disease prevention and control of T. gondii transmission.

Molecular Detection of Toxoplasma gondii in the Slaughter Sheep and Goats from Shandong Province, Eastern China

It is generally recognized that sheep are susceptible to Toxoplasma gondii and play a very important role in the transmission of toxoplasmosis to humans. In China, sheep toxoplasmosis has been reported in some regions based on serological investigations. However, little is known about sheep toxoplasmosis in Shandong province, eastern China. Thus, this study was conducted to investigate the prevalence of T. gondii infection in the slaughter sheep and goats from three cities (Weihai, Yantai, and Rizhao) of Shandong province, eastern China. From November 2016 to March 2018, a total of 692 meat samples (438 sheep and 254 goats) were collected and detected by a seminested PCR-targeted T. gondii B1 gene. The overall prevalence of T. gondii in sheep and goats were 9.84% and 10.73%, respectively. Meat collected from rural markets (16.04%) had a significantly higher T. gondii prevalence than those collected from supermarkets (6.84%) (p < 0.001). Moreover, sheep and goats raised in backyard were more easily to be infected by T. gondii compared with those raised in farms (p < 0.001). This is the first report of the molecular prevalence of T. gondii infection in sheep and goats in Shandong province, eastern China, which would provide effective data for prevention and control of sheep and human toxoplasmosis in China.

Toxoplasmosis Seroprevalence in Romanian Children

The seroprevalence of Toxoplasma gondii in Romanian children is currently unknown. A serological survey was undertaken to determine T. gondii infection among children from Western Romania. Serum samples of 441 children (aged 1-18 years) were screened for T. gondii immunoglobulin G and immunoglobulin M antibodies. The overall T. gondii seroprevalence was 16.6% and tended to increase with age. Seroprevalence was 18.4% in children from rural regions and 14.7% in those from urban regions. T. gondii antibodies were demonstrated in 19.5% of females and 13.3% of males. This report provided the first seroepidemiological data and evaluated the demographic risk factors regarding T. gondii infection in children from Western Romania. Our results may serve as a basis for a future prevention program for toxoplasmosis.

Screening of Zoonotic Parasites in Playground Sandboxes of Public Parks from Subtropical Mexico

The pathological agents Toxoplasma gondii, Ancylostoma caninum, and Toxocara canis are widely distributed zoonotic parasites with high prevalence in tropical and subtropical regions of the world. The aim of the present study was to determine the presence of DNA from these parasites in sand samples from the sand playgrounds in the southeastern region of Mexico. Samples of sand were collected from 68 playgrounds in public parks in the city of Merida, Yucatan, which is the main urban area in the southeast of Mexico. The samples were examined using nested PCR to detect the SAG1 gene from Toxoplasma gondii, and endpoint PCR for the amplification of ITS-2 and rRNA-ITS2 genes from Toxocara canis and Ancylostoma caninum, respectively. The presence of T. gondii DNA was detected in 11.8% (8/68) samples, DNA from A. caninum and T. canis was not detected. Results indicate that playgrounds from the studied sandboxes are contaminated with T. gondii oocysts and may represent a risk of infection for people in contact with the sand, especially for preschoolers.

Seroprevalence and risk factors of Toxoplasma gondii infection in children with leukemia in Shandong Province, Eastern China: a case-control prospective study

Limited information is available concerning the epidemiology of Toxoplasma gondii infection in children with leukemia in Eastern China. Therefore, a case-control study was conducted to estimate the seroprevalence of toxoplasmosis in this patient group and to identify risk factors and possible routes of infection. Serum samples were collected from 339 children with leukemia and 339 age matched health control subjects in Qingdao from September 2014 to March 2018. Enzyme linked immunoassays were used to screen anti- T. gondii IgG and anti- T. gondii IgM antibodies. Forty-eight (14.2%) children with leukemia and 31 (9.1%) control subjects were positive for anti-T. gondii IgG antibodies (P < 0.05), while 13 (3.8%) patients and 14 (4.1%) controls were positive for anti-T. gondii IgM antibodies (P = 0.84). Multivariate analysis showed exposure to soil and a history of blood transfusion were risk factors for T. gondii infection. Compared with IgG, patients with a history of blood transfusion were more likely to present anti- T. gondii IgM (P = 0.003). Moreover, patients with chronic lymphocytic leukemia and acute lymphocytic leukemia had higher T. gondii seroprevalence in comparison to control subjects (P = 0.002 and P = 0.016, respectively). The results indicated that the seroprevalence of T. gondii infection in children with leukemia is higher than that of healthy children in Eastern China. This information may be used to guide future research and clinical management, and further studies are necessary to elucidate the role of T. gondii in children with leukemia.

A Large-Scale Serological Survey of Toxoplasma gondii Infection Among Persons Participated in Health Screening in Yunnan Province, Southwestern China

Surveys of Toxoplasma gondii infection in animals have been reported in Yunnan province, southwestern China. However, limited information is available regarding the epidemiology of T. gondii infection among persons participated in health screening in Yunnan. From January 2014 to December 2016, a large-scale and cross-sectional serological survey was conducted to reveal the seroprevalence of T. gondii infection in persons participated in health screening in three major hospitals. A total of 64,533 serum samples were collected and anti-T. gondii antibodies were examined by commercially available enzyme-linked immunosorbent assay kits. The total seroprevalence of T. gondii infection was 6.67% (4306/64,533). Of these, 3721 persons (5.77%, 3721/64,533) were positive for Immunoglobulin G (IgG) only, 473 persons (0.73%, 473/64,533) were positive for Immunoglobulin M (IgM) only, and 112 persons (0.17%, 112/64,533) were positive for both IgG and IgM. Female seroprevalence (6.83%, 3167/46,389) was higher than male (6.28%, 1139/18,144). The highest seroprevalence of T. gondii infection was found in the age range of 41-50 years (10.60%, 228/2150) (p < 0.001). The seroprevalence in 2014, 2015, and 2016 were 6.39% (1083/16,946), 6.24% (1261/20,201), and 7.16% (1962/27,386), respectively. The results showed that T. gondii infection is common in persons participated in health screening in Yunnan province, which has significant public health concern. Thus, improved integrated measures should be executed to prevent and control T. gondii infection humans and animals in Yunnan province.

Seroprevalence and Related Factors of Toxoplasma gondii in Pigeons Intended for Human Consumption in Northern China

Toxoplasma gondii, the causative agent of toxoplasmosis, is carried by a range of intermediate hosts, including pigeons. Eating raw or undercooked pigeon meat, as is common in regions of China, can easily pass on a potentially fatal T. gondii infection. However, there are little data about the seroprevalence and genotypes of T. gondii infection in pigeons. In this study, a total of 963 pigeon blood samples were collected from Jilin Province, Liaoning Province, and Inner Mongolia Autonomous Region in China between August 2015 and December 2016. The overall seroprevalence of T. gondii was 10.80% (104/963), with 8.80% (41/466) in males and 12.68% (63/497) in females. The seroprevalence of T. gondii in different regions varied from 9.04% (17/188) in Jilin City to 13.16% (20/152) in Shenyang City, a relatively high prevalence. The seroprevalence of T. gondii in juvenile pigeons (6.38%, 18/282) was significantly lower than in adults (86/681, p < 0.05). These findings could provide useful data for the execution of effective control measures against T. gondii infection in pigeons and/or other hosts. More importantly, the findings also suggest that pigeons should not be eaten raw.

Seroprevalence and risk factors of Toxoplasma gondii infection in horses in Jilin Province and Inner Mongolia Autonomous Region, northern China

Toxoplasmosis is caused by the protozoon Toxoplasma gondii that can infect almost all warm-blooded hosts including horses and humans. Horse meat is one of the most important meat products for human consumption. However, data on seroprevalence of T. gondii in horses intended for human consumption in Northern China is scarce. Thus, a total of 614 serum samples were collected from Jilin Province and Inner Mongolia Autonomous Region (IMAR) between 2015 and 2017, and were detected the seroprevalence for T. gondii by indirect hemagglutination assay test. In the prevalence study, the overall seroprevalence of T. gondii in horses was 17.92% (110/614) by IHA test, at the cut- off 1:64. Horses collected from Changchun (13.58%, P = 0.02) has a significantly lower seroprevalence than those from Meihekou City (21.72%) and Tongliao City (22.81%). Moreover, a significant difference of T. gondii seroprevalence was found between horses ages at less than 12 months (22.75%) and ≥12 months or higher (16.42%, P = 0.002). To our knowledge, this is the first report of seroprevalence of T. gondii in horses in Jilin and IMAR, Northern China. Logistic regression suggested that age and geographical location of horses were identified as risk factors. These findings will provide the useful data for controlling and preventing toxoplasmosis in horses and/or other hosts in China.

Seroprevalence and associated risk factors of Toxoplasma gondii among Manchu pregnant women in northeastern China

Toxoplasma gondii is an intracellular protozoan parasite infecting human and almost all warm-blooded animals. It may cause several severe symptoms if pregnant women infection with T. gondii, including misbirth. A cross-sectional study was conducted containing 313 Manchu pregnant women attending antenatal care from 2016 to 2017 in Jilin province, northeastern China, and were assessed by enzyme-link immunosorbent assay and the study utilized univariate analysis to identify the potential risk factors for T. gondii infection. Of the 313 investigated Manchu pregnant women, 51 (16.29%, 95% CI 12.2-20.4) were tested as T. gondii-seropositive, with 47 (15.02%) seropositive for T. gondii IgG antibodies and 8 (2.56%) IgM positive. The seroprevalence of T. gondii in different age groups varied from 13.50% (8.7-18.3) to 23.90% (13.9-41.9). Pregnant raising cat at home has a significantly higher seroprevalence of T. gondii than no cat at home. Pregnant consuming raw/undercooked meat has a significantly higher T. gondii seroprevalence than individuals did not consuming raw/undercooked meat. This is the first study of T. gondii infection seroprevalence in Manchu pregnant women. Risk factors analysis suggested that seroprevalence of T. gondii in investigated Manchu pregnant women was mainly related to consumption of raw/undercooked meat and raising cat at home. The findings will provide key and baseline data for prevention and control of toxoplasmosis among Manchu pregnant women and other people.

Land use and soil contamination with Toxoplasma gondii oocysts in urban areas

Because soil contaminated with Toxoplasma gondii oocysts is increasingly recognized as a major source of infection for humans, in this study, we investigated the spatial pattern of soil contamination with T. gondii oocysts in urban area of northeastern Mainland China. From April 2014 to May 2015, more than 9000 soil samples were collected. Detection of T. gondii oocysts was performed applying real-time quantitative PCR. Sensitivity was improved by analyzing four replicates for each sampling point. T. gondii was detected in 30.3% of all samples. Subsequently, a maximum entropy model was used to evaluate the effect of land use and intrinsic soil properties on the risk of contamination with oocysts. Jackknife analysis revealed that the likelihood for positive results is significantly enhanced in soil originating from foci of human habitation, wood land and grass land. Furthermore, soil temperature and humidity significantly influence the probability of contamination with T. gondii oocysts. Our findings indicate that land use may affect distribution of T. gondii oocysts in urban areas.

Major parasitic diseases of poverty in mainland China: perspectives for better control

Significant progress has been made in the prevention, control, and elimination of human parasitic diseases in China in the past 60 years. However, parasitic diseases of poverty remain major causes of morbidity and mortality, and inflict enormous economic costs on societies.In this article, we review the prevalence rates, geographical distributions, epidemic characteristics, risk factors, and clinical manifestations of parasitic diseases of poverty listed in the first issue of the journal Infectious Diseases of Poverty on 25 October 2012. We also address the challenges facing control of parasitic diseases of poverty and provide suggestions for better control.

Seroepidemiology of Toxoplasma gondii in pregnant women in Aguascalientes City, Mexico: a cross-sectional study

OBJECTIVES

We determined the seroprevalence and correlates of Toxoplasma gondii infection in pregnant women in Aguascalientes City, Mexico.

DESIGN

A cross-sectional survey.

SETTING

Pregnant women were enrolled in the central Mexican city of Aguascalientes.

PARTICIPANTS

We studied 338 pregnant women who attended prenatal care in 3 public health centres.

PRIMARY AND SECONDARY OUTCOME MEASURES

Women were examined for IgG/IgM antibodies to T. gondii by using commercially available enzyme immunoassays, and an avidity test. Multiple analyses were used to determine the association of T. gondii seropositivity with the characteristics of the pregnant women.

RESULTS

Of the 338 pregnant women studied, 21 (6.2%) had IgG antibodies to T. gondii, and 1 (4.8%) of them was also positive for IgM antibodies to T. gondii. Avidity of IgG antibodies to T. gondii was high in the IgM-positive sample. Logistic regression analysis of sociodemographic, behavioural and housing variables showed that T. gondii seropositivity was associated with white ethnicity (OR=149.4; 95% CI 10.8 to 2054.1; p<0.01), not washing hands before eating (OR=6.41; 95% CI 1.73 to 23.6; p=0.005) and use of latrine (OR=37.6; 95% CI 4.63 to 306.31; p=0.001).

CONCLUSIONS

Results demonstrate that pregnant women in Aguascalientes City have a low seroprevalence of T. gondii infection. However, this low prevalence indicates that most pregnant women are at risk for a primary infection. Factors associated with T. gondii exposure found in this study, including food hygiene, may be useful to determine preventive measures against T. gondii infection and its sequelae.

Seroprevalence and associated risk factors ofToxoplasma gondiiinfection in the Korean, Manchu, Mongol and Han ethnic groups in eastern and northeastern China

A cross-sectional study was conducted from June 2013 to August 2015 to determine the seroprevalence and possible risk factors for humanToxoplasma gondiiinfection in Korean, Manchu, Mongol and Han ethnic groups in eastern and northeastern China. A total of 1842 serum samples, including Han (n= 802), Korean (n= 520), Manchu (n= 303) and Mongol (n= 217) groups, were analysed using enzyme-linked immunoassays to detect IgG and IgMT. gondiiantibodies. The overallT. gondiiIgG and IgM seroprevalences were 13·79% and 1·25%, respectively. Of these groups, Mongol ethnicity had the highestT. gondiiseroprevalence (20·74%, 45/217), followed by Korean ethnicity (16·54%, 86/520), Manchu ethnicity (13·86%, 42/303) and Han ethnicity (11·35%, 98/802). Multiple analysis showed that the consumption of raw vegetables and fruits, the consumption of raw/undercooked meat and the source of drinking water were significantly associated withT. gondiiinfection in the Han group. Likewise, having a cat at home was identified as being associated withT. gondiiinfection in the Korean, Manchu and Mongol groups. Moreover, the consumption of raw/undercooked meat was identified as another predictor ofT. gondiiseropositivity in the Mongol group. The results of this survey indicate thatT. gondiiinfection is prevalent in Korean, Manchu, Mongol and Han ethnic groups in the study region. Therefore, it is essential to implement integrated strategies with efficient management measures to prevent and controlT. gondiiinfection in this region of China. Moreover, this is the first report ofT. gondiiinfection in Korean, Manchu, and Mongol ethnic groups in eastern and northeastern China.

Seroprevalence of Toxoplasma gondii infection among patients with hand, foot and mouth disease in Henan, China: a hospital-based study

Background

The prevalence of infection with Toxoplasma gondii (T. gondii) in humans has been increasing in China due to the growing number of cats in the country. Hand, foot and mouth disease (HFMD) is a serious public health issue in China and still one of the leading causes of child mortality. However, little is known about the epidemiology of T. gondii infection among HFMD patients.

Methods

A case–control study of 281 HFMD patients from the First People’s Hospital of Pingdingshan in Pingdingshan city, Henan province, central China, and 222 controls from Pingdingshan city was conducted. Anti-T. gondii antibodies were serologically detected using the enzyme-linked immunosorbent assay.

Results

We found that the overall anti-T. gondii immunoglobulin G (IgG) antibody prevalence among HFMD patients was 12.46 %, which was significantly higher than that in clinically healthy children (1.80 %). The highest T. gondii seroprevalence was detected in critical cases (22.58 %), followed by severe cases (11.50 %), and the lowest was detected in mild cases (8.33 %).

Conclusion

The present study is the first survey of T. gondii seroprevalence among HFMD patients in China; 12.46 % were defined as seropositive. It is imperative that improved integrated measures are taken to prevent and control T. gondii infection among HFMD patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-015-0088-3) contains supplementary material, which is available to authorized users.

Seroprevalence of Toxoplasma gondii Among Primary School Children in Shandong Province, China

Although Toxoplasma gondii infection in primary school children has been investigated in many countries, limited surveys have been available in primary school children in China. In the present study, we report the seroprevalence of T. gondii infection in primary school children in Shandong province, China. Sera from 6,000 primary school children were evaluated for T. gondii antibodies with ELISA. The overall seroprevalence of T. gondii infection was 16.0% (961/6,000), of which 14.5% (870/6,000) were positive for anti-T. gondii IgG antibodies, 3.4% (206/6,000) positive for IgM, and 1.9% (115/6,000) were positive for both IgG and IgM. The results of the present investigation indicated a high seroprevalence of T. gondii infection in primary school children in Shandong province, China. Therefore, effective measures should be taken to prevent and control T. gondii infection in primary school children in this province. To the best of our knowledge, this is the first report of T. gondii seroprevalence in primary school children in Shandong province, China.

Seroprevalence of Toxoplasma gondii Infection in Patients of Intensive Care Unit in China: A Hospital Based Study

The objective of this study was to estimate the seroprevalence of Toxoplasma gondii infection in 394 patients of intensive care unit (ICU) in a hospital between April 2010 and March 2012 and analyze the association between T. gondii infection and ICU patients according to the species of disease. Toxoplasma serology was evaluated by ELISA method using a commercially available kit. Data of patients were obtained from the patients, informants, and medical examination records. Seventy-four (18.78%) of 394 patients were positive for anti-T. gondii IgG antibodies demonstrating latent infection. Of these, the highest T. gondii seroprevalence was found in the age group of 31–45 years (27.45%), and the lowest was found in the age group of <30 years (12.5%). In addition, females (21.6%) had a higher seroprevalence than males (18.36%). With respect to the species of disease, the patients with kidney diseases (57.14%), lung diseases (27.84%), and brain diseases (24%) had high T. gondii seroprevalence. The present study represents the first survey of T. gondii seroprevalence in ICU patients in China, revealing an 18.78% seropositivity. Considering the particularities of ICU patients, molecular identification, genetic characterization, and diagnosis of T. gondii should be considered in future study.