SEROPREVALENCE AND RISK FACTOR OF TOXOPLASMOSIS IN SCHIZOPHRENIA PATIENTS REFERRED TO GRHASIA PSYCHIATRIC HOSPITAL, YOGYAKARTA, INDONESIA

Global seroprevalence of Toxoplasma gondii infection among patients with mental and neurological disorders: A systematic review and meta-analysis

Background and Aim

Toxoplasmosis is the most widespread zoonotic disease that affects one-third of the world's population, and imposes a major public health problem worldwide. This study aimed to assess the prevalence of toxoplasmosis among patients with neuropsychiatric patients.

Methods

Electronic databases PubMed, Google Scholar, Web of Science, Research Gate, and Scopus were thoroughly searched from February to March 2022 to identify all relevant studies. The quality of studies was evaluated using the Newcastle-Ottawa quality scale for case-control and cross-sectional studies. Statistical analysis was done using STATA version 12 software. A random effect model was used to compute the global pooled seroprevalence of Toxoplasma gondii infection. Heterogeneity was quantified by using I 2 value. Subgroup analysis was done, and publication bias was assessed using a funnel plot and Egger's test.

Result

Of 1250 studies, 49 containing 21,093 participants and conducted in 18 countries were included. The global pooled seroprevalence of T. gondii IgG antibody was 38.27% (95% CI: 32.04-44.9) among neuropsychiatric patients and 25.31% (95% CI: 21.53-29.08) in healthy controls with substantial heterogeneity of 98.3%. The prevalence of T. gondii IgG antibody was higher in males (17.52%) than in females (12.35%) neuropsychiatric patients. The highest pooled prevalence of T. gondii IgG antibody was in Europe (57%) followed by Africa (45.25%) and Asia (43%). Time based analysis showed the highest pooled prevalence of T. gondii IgG antibody in 2012-2016 (41.16%).The global pooled seroprevalence T. gondii IgM antibody among neuropsychiatric patients and healthy controls was 6.78% (95% CI: 4.87-8.69) and 3.13% (95% CI: 2.02-4.24), respectively.

Conclusion

The pooled prevalence of chronic and acute T. gondii infection among neuropsychiatric patients was 38.27% and 6.78%, respectively. This showed a high burden of toxoplasmosis among neurological and psychiatric patients and urges routine screening of those patients and providing appropriate treatment. It also indicates the need for different stakeholders to develop targeted prevention and control strategies for T. gondii infection.

Neurological and Neurobehavioral Disorders Associated with Toxoplasma gondii Infection in Humans

The intracellular parasite Toxoplasma gondii is estimated to infect up to 30% of the world population, leading to lifelong chronic infection of the brain and muscle tissue. Although most latent T. gondii infections in humans have traditionally been considered asymptomatic, studies in rodents suggest phenotypic neurological changes are possible. Consequently, several studies have examined the link between T. gondii infection and diseases such as schizophrenia, epilepsy, depression, bipolar disorder, dysphoria, Alzheimer's disease, Parkinson's disease, and obsessive-compulsive disorder (OCD). To date, there is varying evidence of the relationship of T. gondii to these human neurological or neurobehavioral disorders. A thorough review of T. gondii literature was conducted to highlight and summarize current findings. We found that schizophrenia was most frequently linked to T. gondii infection, while sleep disruption showed no linkage to T. gondii infection, and other conditions having mixed support for a link to T. gondii. However, infection as a cause of human neurobehavioral disease has yet to be firmly established.

Toxoplasmosis Is More Frequent in Schizophrenia Patients Than in the General Population in Mexico and Is Not Associated with More Severe Course of Schizophrenia Measured with the Brief Psychiatric Rating Scale

Toxoplasmosis is a disease, which was discovered in 1908, caused by the intracellular parasite Toxoplasma gondii. T. gondii infects neuronal, glial, and muscle cells, and chronic infections are characterized by the presence of cysts, in the brain and muscle cells, formed by bradyzoites. T. gondii is capable of synthesizing L-DOPA, a precursor of dopamine. Dopamine is a neurotransmitter that is key in the etiology of neuropsychological disorders such as schizophrenia. Previous studies have shown high levels of IgG Toxoplasma antibodies in schizophrenia patients. Many published studies show that the prevalence of toxoplasmosis is higher in schizophrenia patients. In this study, we aimed to identify the prevalence of Toxoplasma infection in patients with schizophrenia and the relationships between, sociodemographic factors and the Brief Psychiatric Rating Scale. A total of 27 schizophrenic patients were included and IgG anti-T. gondii was determined in serum samples by ELISA. The Brief Psychiatric Rating Scale, sociodemographic factors were associated with seropositivity. We found that the prevalence of Toxoplasma antibodies was 51.7%. In the Brief Psychiatric Rating Scale, statistical significant association (p = 0.024) was found in Item 13 which is related to motor retardation, however, the association turned non-significant after of correction for multiple tests or after of analyzed with a logistic regression p = 0.059, odds ratio (OR) = 2.316 with a 95% confidence interval [0.970 to 5.532]. Other association was not found between toxoplasmosis and others factors. The prevalence of toxoplasmosis on our population under study was significantly higher than that reported by general population or other group of Mexican schizophrenia patients.

Current Status of Parasite Infections in Indonesia: A Literature Review

Indonesia and South Korea have become inseparable in various respects since the 2 countries established diplomatic relation in 1973. Indonesia is a tropical region that stretches across the equator, comprised of 5 main islands (Java, Kalimantan, Sumatra, Sulawesi, and Papua) and 4 archipelagoes (Riau, Bangka Belitung, Nusa Tenggara, and Maluku). As most population of Eastern Indonesia (Sulawesi, Papua and Nusa Tenggara & Maluku) live in poor areas, it is expected that there will be many parasites. Nevertheless, little is known about the status of parasites in Indonesia. This study examines the prevalences of malaria and lymphatic filaria, which are prevalent in Indonesia, as well as those of soil-transmitted-helminths (STH). As a result, the Plasmodium falciparum and P. vivax case loads are almost equal. The current prevalence of P. vivax is uniformly low (<5%) in all age groups and annual parasite incidence (API) showed decreasing tendency as 0.84 per 1,000 population in 2016. However, more than 65 million people still live in malaria epidemic regions. Lymphatic filariasis remains an important public health problem and 236 cities were classified as endemic areas in 514 cities/districts in 2017. It is difficult to ascertain the current prevalence rate of STH in Indonesia, although West Sumba and Southwest Sumba in East Nusa Tenggara reported prevalence rate of more than 20%. The study also considers the (sero) prevalences of other parasites identified in Indonesia. This report should be useful not only to parasitologists but also to travelers and people with business in Indonesia.