METHODS: The demographic profiles for each participant were obtained through a questionnaire survey prior to blood collection. A total of 389 participants were recruited and blood samples screened for the presence of anti-Toxoplasma IgG and IgM antibody using an ELISA commercial kit, SERION ELISA classic Toxoplasma gondii IgG and IgM.
RESULTS: The overall T. gondii seroprevalence was 69.6% with 56.8% seropositive for anti-Toxoplasma IgG, 7.7% seropositive for anti-Toxoplasma IgM and 5.1% seropositive for both IgG and IgM antibodies. The presence of both antibody classes in blood samples indicated high avidity, suggesting latent infection. Univariate analysis revealed significant associations that included; age, ethnicity, location and employment status while, significant lifestyle factors included source of drinking water and eating style. A multifactorial statistical model that incorporated all the significant effects from the first-stage univariate analyses listed above revealed that age and ethnicity were the two dominant and independent effects on IgG seroprevalence. For seroprevalence of IgM, the multifactorial model revealed a significant interaction between work and accommodation. IgM seroprevalence was higher among the unemployed inhabitants of PPR (Program Perumahan Rakyat) than those living in non-PPR accommodation, and higher than among the employed irrespective of their accommodation.
CONCLUSION: High seroprevalence of Toxoplasmosis in the community calls for increased awareness of disease transmission and improvements in hygiene and sanitation.
METHODS: To understand the research status of schistosomiasis and toxoplasmosis in China, academic articles published in Chinese journals from 1980 to 2021 were retrieved from China National Knowledge Infrastructure (CNKI) and Wanfang databases. The Bibliographic Items Co-occurrence Matrix Builder (BICOMB) software was used to extract and analyze the keyword frequencies. The 'K/A ratio' as the frequency of a keyword that occurred in all the articles within a certain time stage was calculated to compare the popularity of the same keyword in different time stages. Keyword co-occurrence network maps were constructed by VOSviewer software.
RESULTS: A total of 18,508 articles in the research field of Schistosoma and 13,289 articles in the field of Toxoplasma gondii were included. Results in both fields showed some similarities: the annual number of articles presented an increasing trend before entering the 21st century and decreased rapidly in recent years. Two opposite changing trends of keyword frequency could be observed in the K/A ratio analysis: the K/A ratios of 'Surveillance' and 'Infection' continuously increased over time, while those of 'Schistosoma mansoni' and 'Mesenteric lymph nodes' decreased. The diversification of keyword co-occurrence networks could be observed in the co-occurrence network maps.
CONCLUSIONS: This bibliometric analysis reveals trends in research themes in the fields of Schistosoma and Toxoplasma gondii from 1980 to 2021, presenting China's experience such as a high degree of government involvement and multidisciplinary participation in schistosomiasis and toxoplasmosis control and elimination.
METHODS: A total of 1267 suspected cases of Toxoplasma infection were enrolled in this study from January 2016 to December 2016. The cases were screened for anti-Toxoplasma IgM and IgG by electrochemiluminiscence immunoassay (ECLIA) method. Based on the serological profiles, all cases with first seropositive serum samples were considered as suggestive cases of Toxoplasma infection. Thus, second serum samples were obtained after an interval of 2 weeks. The diagnosis was made based on laboratory results and clinical data.
RESULTS: A total of 482 T. gondii seroreactive cases were selected. The patient's records were traced and the data were analysed. Accordingly, 152 cases were diagnosed as clinically confirmed cases; 198 cases were clinically asymptomatic and 132 cases were newborn babies or infants who did not have toxoplasmosis and only acquired passive immunity from their mothers. The paired serum algorithm allowed classifying the seroreactive cases as follows: early (0.6%), acute (1.9%), reactivation (13.5%), recent (1.5%), passive immunity from mother (27.3%) and possible congenital infections (1.2%). In addition, cases of reactivated toxoplasmosis were detected among the pregnant mothers (13/82; 15.8%), children aged above 1 year (2/8; 25.0%) and immunocompetent mothers (5/135; 3.7%). Furthermore, the application of the paired serum analysis resulted in remarkably improved treatment initiation.
CONCLUSIONS: Toxoplasmosis diagnosis and treatment can be improved through the use of paired serum diagnostic algorithm.
METHODS: An indirect enzyme-linked immunosorbent assay (ELISA) was developed to evaluate the usefulness of USM.TOXO1 antigen for the detection of IgG antibodies against Toxoplasma gondii in human sera. Whereas the reactivity of the developed antigen against IgM antibody was evaluated by western blot and Dot enzyme immunoassay (dot-EIA) analysis.
RESULTS: The diagnostic performance of the new antigens in IgG ELISA was achieved at the maximum values of 85.43% and 81.25% for diagnostic sensitivity and specificity respectively. The USM.TOXO1 was also proven to be reactive with anti- T. gondii IgM antibody.
CONCLUSIONS: This finding makes the USM.TOXO1 antigen an attractive candidate for improving the toxoplasmosis serodiagnosis and demonstrates that multiepitope antigens could be a potential and promising diagnostic marker for the development of high sensitive and accurate assays.
RESULTS: An earlier published work discovered a highly antigenic 12 kDa excretory-secretory (ES) protein of T. gondii which may potentially be used for the development of an antigen detection test for toxoplasmosis. However, the three-dimensional structure of the protein is unknown. Since epitope identification is important prior to designing of a specific antibody for an antigen-detection based diagnostic test, the structural elucidation of this protein is essential. In this study, we constructed a three dimensional model of the 12 kDa ES protein. The built structure possesses a thioredoxin backbone which consists of four α-helices flanking five β-strands at the center. Three potential epitopes (6-8 residues) which can be combined into one "single" epitope have been identified from the built structure as the most potential antibody binding site.
CONCLUSION: Together with specific antibody design, this work could contribute towards future development of an antigen detection test for toxoplasmosis.