Schizophrenia – Toxoplasma gondii & Human Phenotype

The role of latent toxoplasmosis in the aetiopathogenesis of schizophrenia–the risk factor or an indication of a contact with cat?

February 6, 2020
Yuksel, P., Alpay, N., Babur, C., Bayar, R., Saribas, S., Karakose, A. R., Aksoy, C., Aslan, M., Mehmetali, S., Kilic, S., Balcioglu, I., Hamanca, O., Dirican, A., Kucukbasmaci, O., Oner, A., Torun, M. M., Kocazeybek, B.
Folia Parasitol (Praha) 2010, 57: 121 - 128 Adult Aged Animals Antibodies, Protozoan/blood Case-Control Studies Cats Cross-Sectional Studies Female Humans Immunoglobulin G/blood Male Middle Aged Retrospective Studies Risk Factors Schizophrenia/*blood/*etiology Toxoplasmosis/blood/*complications/immunology

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Toxoplasma gondii – obsessive -compulsive disorder relationship: is it different in children?

February 6, 2020
Miman, O., Ozcan, O., Unal, S., Atambay, M.
Nordic Journal of Psychiatry 2019, 72: 501 - 505

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Presence of Toxoplasma gondii infection in brain as a potential cause of risky behavior: a report of 102 autopsy cases

February 1, 2020
Samojlowicz, D. Twarowska-Malczynska, J. Borowska-Solonynko, A. Poniatowski, L. A. Sharma, N. Olczak, M.
European Journal of Clinical Microbiology and Infectious Diseases 2019, 38: 305 - 317 Toxoplasma gondii Toxoplasmosis Brain Risky behavior Alcohol Mental health Drivers cerebral toxoplasmosis decreased level novelty seeking dopamine parasite host schizophrenia personality depression strategies

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Relationship between toxoplasmosis and obsessive compulsive disorder: A systematic review and meta-analysis

February 1, 2020
Nayeri Chegeni, T., Sarvi, S. Amouei, A. Moosazadeh, M. Hosseininejad, Z. Aghayan, S. A. Daryani, A.
PLoS Neglected Tropical Diseases 19, 13

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Background A few studies investigated the relationship between toxoplasmosis and mental disorders, such as obsessive compulsive disorder (OCD). However, the specific nature of the association between Toxoplasma gondii (T. gondii) infection and OCD is not yet clear. The aim of this study was to collect information on the relationship between OCD and toxoplasmosis and assess whether patients with toxoplasmosis are prone to OCD. Methods For the purpose of this study, 6 major electronic databases and the Internet search engine Google Scholar were searched for the published articles up to July 30(th), 2018 with no restriction of language. The inverse variance method and the random effect model were used to combine the data. The values of odds ratio (OR) were estimated at 95% confidence interval (CI). Results A total of 9 case-control and 3 cross-sectional studies were included in our systematic review. However, 11 of these 12 articles were entered into the meta-analysis containing 9873 participants, out of whom 389 were with OCD (25.96% positive for toxoplasmosis) and 9484 were without OCD (17.12% positive for toxoplasmosis). The estimation of the random effect model indicated a significant common OR of 1.96 [95% CI: 1.32-2.90]. Conclusion This systematic review and meta-analysis revealed that toxoplasmosis could be as an associated factor for OCD (OR = 1.96). However, further prospective investigations are highly recommended to illuminate the underlying pathophysiological mechanisms of T. gondii infection in OCD and to better investigate the relationship between OCD and T. gondii infection. Author summary Toxoplasma gondii (T. gondii) is an obligate neurotropic parasite that infected about 25-30% of the total human population in the developed and developing countries. The obsessive compulsive disorder (OCD) is a psychiatric disease that affects the income and quality of life. Some studies confirmed an association between infectious agents as the associated or protective factors specifying the development of psychiatry diseases. Among various pathogens associated with psychological disorders, most of the attention is on T. gondii, which has a life-long asymptomatic latent phase after a short acute stage in healthy individuals. The detrimental effect of T. gondii on immunocompromised people and pregnant women is an important concern for public health. The correlation between toxoplasmosis and OCD is still relatively understudied with a paucity of documented findings. The previous meta-analysis reviewed only two studies and reported a 3.4-fold greater chance of OCD. The results of our study presented stronger evidence of a positive relationship between toxoplasmosis and OCD. Eventually, our research team hopes to present an overview of what is known and encourage more intensive research to determine the real impact of this parasite on the occurrence of OCD that may contribute to the prevention of OCD worldwid

Toxoplasma gondii – obsessive -compulsive disorder relationship: is it different in children?

February 1, 2020
Miman, O., Ozcan, O., Unal, S., Atambay, M.
Nordic Journal of Psychiatry 2019, 72: 501 - 505

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Epidemiologic studies of exposure to prenatal infection and risk of schizophrenia and autism

February 1, 2020
Brown, A. S.
Developmental Neurobiology 2012, 72: 1272 - 1276

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Is there any association between Toxoplasma gondii infection and depression? A systematic review and meta-analysis

January 31, 2020
Chegeni, T. N., Sharif, M., Sarvi, S., Moosazadeh, M., Montazeri, M., Aghayan, S. A., Balalami, N. J., Gholami, S., Hosseininejad, Z., Saberi, R., Anvari, D., Gohardehi, S., Daryani, A.
PLoS ONE 2019, 14

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Background Toxoplasma gondii (T. gondii) is an obligate intracellular opportunistic parasite that is the causative agent of toxoplasmosis. This parasite accounts for mental disorders; however, the relationship between T. gondii infection and depressive disorder is unclear. Regarding this, the present systematic review and meta-analysis was conducted to investigate the scientific evidence regarding the potential association between major depression disorder (MDD) and Toxoplasma infection. Methods For the purpose of the study, the articles related to the subject of interest were systematically searched in seven electronic databases. Special attention was given to the studies examining T. gondii seropositivity level in depressed patients and controls. Results The search process resulted in the identification of a total of 30 publications meeting the inclusion criteria and published up to April 2018 for the systematic review. Furthermore, 29 studies met the inclusion criteria to be entered into meta-analysis. Our meta-analysis involved the review of cross-sectional studies including 1657 depressed patients and 19565 individuals as controls and case-control studies entailing 1311 depressed cases and 6015 controls without depression. 1582 depressed people participated in cross-sectional studies whose results were reported as odds ratio (OR). In addition, the total number of participants was 15068 in this type of studies. Statistical analysis indicated that the pooled OR of the risk of anti-T. gondii IgG antibody in depressed individuals in case-control and cross-sectional studies was 1.15 (95% confidence interval (CI): 0.95-1.39). Conclusions As the findings of the reviewed articles indicated, toxoplasmosis is not a risk factor for MDD. However, it is necessary to perform further research to clarify the detailed association between T. gondii and dysthymia or mild and moderate depression. Furthermore, it is recommended to better investigate the effect of antibody titers on the relationship between depression and T. gondii infection.

Sero-prevalence of Toxoplasma gondii and associated risk factors among psychiatric outpatients attending University of Gondar Hospital, Northwest Ethiopia

January 31, 2020
Achaw, B., Tesfa, H., Zeleke, A.J., Worku, L., Addisu, A., Yigzaw, N., Tegegne, Y.
BMC Infectious Diseases 2019, 19 Ethiopia

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BackgroundToxoplasmosis is caused by an obligatory intracellular coccidian protozoan organism, Toxoplasma gondii. It has a worldwide distribution, affecting one-third of the world population. Psychiatric patients have a higher risk of exposure to Toxoplasma gondii infection due to lack of good personal hygiene. The burden of toxoplasmosis among psychiatric patients in Ethiopia has not been studied extensively. Thus, the study aimed to determine the seroprevalence of Toxoplasma gondii and associated risk factors among psychiatric outpatients at the University of Gondar Comprehensive and Specialized Hospital Psychiatric clinic.MethodsA cross-sectional study was conducted at the University of Gondar Comprehensive and Specialized Hospital from February to May 2018. Venous blood was collected from 304 study participants (152 psychiatric outpatients and 152 control groups). Anti-toxoplasma antibodies were determined using Onsite Toxo immunoglobulin G (IgG) and immunoglobulin M (IgM) Rapid Test. A Chi-square test was carried out to compare the two groups and a logistic regression analysis was conducted to check the association between variables. P-value less than 0.05 was taken as statistically significant.ResultsThe seroprevalence rate of anti-Toxoplasma gondii IgG antibodies was 33.6, and 16.4% in the psychiatric outpatients and the control samples, respectively. Anti-Toxoplasma gondii IgM sero-prevalence was 1.3% in the former patients and 3.9% in the latter group. Owing cat (AOR=2.862 95% CI=1.445-5.666 P=0.003), cleaning cat excreta (AOR=2.966 95% CI=1.317-2.652 P=0.007), and farming (AOR=2.058 95% CI=1.018-4.163 P=0.045) were found to be significantly associated with the sero-prevalence of anti-Toxoplasma gondii IgG antibody.ConclusionsThis study highlighted that, the prevalence of anti-Toxoplasma gondii IgG antibodies was significantly higher in psychiatric outpatients than the control group (p=0.001). Cat ownership, cleaning of cat excreta, and farming were found to be statistically significantly associated with the seroprevalence of anti-Toxoplasma gondii IgG antibody.

The effects of latent Toxoplasma gondii infection on the behavior and personality characteristics of university students

January 30, 2020
Akgul, O
Anadolu Psikiyatri Dergisi-Anatolian Journal of Psychiatry 2020, 21: 70 - 76

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Objective: It is well known that one-third of the world population is infected with toxoplasma gondii (T. gondii), and the seroprevalence varies according to socioeconomic status and hygienic habits. Nowadays, it's thought that T. gondii which is related asymptomatic latent infections in brain and muscle tissue may be related with neuropsychiatric conditions. Methods: T. gondii lgG levels of serum samples obtained from 150 volunteer university students who participated in the study according to inclusion criteria were determined according to the manufacturer's recommendations by ELISA (Enzyme-Linked lmmunosorbent Assay) method. Criminal profiles (accident claims, criminal conviction), impulsive behaviors (non-suicidal self-injury, attempted suicide) and personality traits (extra-version, agreeableness, conscientiousness, neuroticism and openness to experience) of the participants were recorded by appropriate scales and/or clinical interviews. The aim of this study was to investigate the relationship between T. gondii seropositivity and impulsive behaviors such as suicide attempt and physical injury, criminal events such as crime and traffic accidents and 5 factor personality types in psychiatric healthy individuals. Results: Sixty-nine (46%) of participants were male and 81 were female (54%), ages ranged from 20 to 37 (25.71 +/- 3.08) and the rate of seropositivity was determined as 30.66%. The relationship between seropositivity and accident claims was not statistically significant; the criminal conviction, non-suicidal self-injury and attempted suicide were statistically correlated. There was no statistically difference in terms of the features of extraversion or openness to experience between seronegative and seropositive groups. However, the T. gondii lgG were statistically highly correlated with lower agreeableness, lower conscientiousness and higher neuroticism scores. Conclusion: The data obtained from our study which is the first study conducted with this context in our country, confirms that latent T. gondii may be associated with negative behavioral outcomes. In order to fully understand the possible effects of T. gondii in psychiatric disorders, prospective-based studies are needed.

Host-parasite interaction associated with major mental illness

January 29, 2020
Kano, S., Hodgkinson, C. A., Jones-Brando, L., Eastwood, S., Ishizuka, K., Niwa, M., Choi, E. Y., Chang, D. J., Chen, Y., Velivela, S. D., Leister, F., Wood, J., Chowdari,K., Ducci, F., Caycedo, D. A., Heinz, E., Newman, E. R., Cascella, N., Mortensen, P. B., Zandi, P. P., Dickerson, F., Nimgaonkar, V., Goldman, D., Harrison, P. J., Yolken, R. H., Sawa, A.
Molecular Psychiatry 2020, 25: 194 - 205

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Association of Cytomegalovirus and Toxoplasma gondii Antibody Titers With Bipolar Disorder

January 29, 2020
Frye, M. A., Coombes, B. J., McElroy, S. L., Jones-Brando, L., Bond, D. J., Veldic, M., Romo-Nava, F., Bobo, W. V., Singh, B., Colby, C., Skime, M. K., Biernacka, J. M., Yolken, R
Jama Psychiatry 2019, 76: 1285 - 1293

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Importance Infection-associated immune activation and inflammation are increasingly recognized in the pathophysiology of bipolar disorder. Objective To determine whether antibodies to common infectious agents, including cytomegalovirus (CMV), Toxoplasma gondii, and measles, as well as the inflammatory marker C-reactive protein, in serum samples differ between patients with bipolar disorder and control individuals without bipolar disorder. Design, Setting, and Participants In this case-control study, antibody titers were measured in serum samples from 1207 patients with bipolar disorder and 745 controls that were obtained from biobanks with participating sites in Rochester and Minneapolis, Minnesota (n = 1537), and Cincinnati, Ohio (n = 415), from January 5, 2009, through May 12, 2014. A subset of case patients and controls from Minnesota were matched by age, sex, and educational level. Bipolar type, age at onset, and history of psychosis were assessed for case patients as well as current drug treatment at the time of blood sample obtainment from the biobank. Data were analyzed from February 5, 2018, to January 4, 2019. Exposures The CMV and T gondii antibodies with IgM titers were expressed as z scores and IgG titers dichotomized into seropositive and seronegative based on expected prevalence in the US population and further classified based on the joint CMV-positive/T gondii-negative IgG status, C-reactive protein z score, and drug treatments with antitoxoplasma activity. Main Outcomes and Measures Patients were stratified by bipolar disorder type I or type II, nonearly (>19 years of age) and early (<= 19 years of age) onset, and history of psychosis during mania or no psychosis. Results Of 1207 patients with bipolar disorder (mean [SD] age, 43.2 [15.1] years; 742 [61.5%] female), the CMV-positive/T gondii-negative IgG status was significantly higher (odds ratio [OR], 1.33; 95% CI, 1.09-1.62; P = .004) compared with that in the 745 controls (mean [SD] age, 44.5 [15.5] years; 444 [59.6%] female). The CMV-positive/T gondii-negative IgG status was associated with bipolar cases type I (OR, 1.41; 95% CI, 1.14-1.75; P = .001), nonearly age at onset (OR, 1.41; 95% CI, 1.16-1.72; P = .001), and history of manic psychosis (OR, 1.46; 95% CI, 1.13-1.88; P = .004). Patients with bipolar disorder who received drug treatment with antitoxoplasma activity (n = 272) had significantly lower T gondii IgM titers (median, 1.59; interquartile range, 1.30-2.07) compared with those (n = 900) who did not receive this treatment (median, 1.69; interquartile range, 1.35-2.25) (P = .03). Conclusions and Relevance In this sample, increased long-term antibody response to CMV and decreased long-term antibody response to T gondii were associated with bipolar disorder and the subphenotypes of bipolar type I, nonearly disease onset, and manic psychosis. Further work appears to be needed to better understand genetic vs environmental disease risk and infection or immune activation contribution to overall disease pathogenesis with particular reference to disease onset. This case-control study analyzes the association of long-term antibody response to cytomegalovirus, Toxoplasma gondii, and measles and of C-reactive protein level with bipolar disorder. Question Is bipolar disorder associated with exposure to infectious agents with immune activation? Findings In this case-control study of 1952 patient cases, cytomegalovirus IgG was significantly increased and toxoplasma IgG was significantly decreased among patients with bipolar disorder compared with control individuals. Patients with bipolar disorder who received drug treatment with antitoxoplasma activity had significantly lower toxoplasma IgM titers compared with those not receiving this treatment. Meaning Increased and decreased long-term antibody response to cytomegalovirus and toxoplasma, respectively, were associated with bipolar disorder in this sample; further work appears to be needed to better understand genetic vs environmental risk of the disease and how infection or immune activation contributes to overall disease pathogenesis with particular reference to disease onset.

Latent Toxoplasmosis and Human

January 29, 2020
Dalimi, A., Abdoli, A.
Iranian Journal of Parasitology 2012, 7: 1 - 17

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Association between Toxoplasma gondii infection and psychiatric disorders in Zhejiang, Southeastern China

April 1, 2019
Chen, X., Chen, B., Hou, X., Zheng, C., Yang, X., Ke, J., Hu, X., Tan, F.
Acta Tropica, 192, 82–86. doi:10.1016/j.actatropica.2019.02.001

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The association between Toxoplasma and the psychosis continuum in a general population setting

September 4, 2018
Lindgren, M., Torniainen-Holm, M., Harkanen, T., Dickerson, F., Yolken, R. H., Suvisaari, J.
Schizophrenia Research 2018; 193: 329-335

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Lower performance of Toxoplasma-infected, Rh-negative subjects in the weight holding and hand-grip tests

September 3, 2018
Flegr, J., Sebankova, B., Priplatova, L., Chvatalova, V., Kankova, S.
PLoS ONE 2018; 13

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Toxoplasmosis, but not borreliosis, is associated with psychiatric disorders and symptoms

August 31, 2018

Schizophrenia Research 2018; 197: 603-604

Is Toxoplasma gondii playing a positive role in multiple sclerosis risk? A systematic review and meta-analysis

August 31, 2018
Saberi, R., Sharif, M., Sarvi, S., Aghayan, S. A., Hosseini, S. A., Anvari, D., Chegeni, T. N., Hosseininejad, Z., Daryani, A.
Journal of Neuroimmunology 2018;322: 57-62

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Toxoplasma antibody titers in mania: A cross sectional study

August 31, 2018
Mangot, A. G., Shivakumar, V., Saini, V., Subbanna, M., Kalmady, S. V., Venkatasubramanian, G.
Journal of Krishna Institute of Medical Sciences University 2018; 7: 13-20

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Immunoglobulin sub-class distribution in bipolar disorder and schizophrenia: potential relationship with latent Toxoplasma Gondii infection

August 31, 2018
Bengoufa, H. D., Godin, O., Doukhan, R., Guen, E. L.,Daban-Huard, C. , Bennabi, M., Delavest, M., Lepine, J. P., Boukouaci, W., Laouamri,H., Houenou, J., Jamain, S., Richard, J. R. , Lecorvosier, P. , Yolken, R., Rajagopal, K., Leboyer, M., Tamouza, R.
Bmc Psychiatry 2018; 18

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Risky business: linking Toxoplasma gondii infection and entrepreneurship behaviours across individuals and countries

August 31, 2018
Johnson, S. K., Fitza, M. A. , Lerner, D. A., Calhoun, D. M., Beldon, M. A. , Chan, E. T., Johnson, P. T. J.
Proceedings of the Royal Society B-Biological Sciences, 2018; 285

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Clinical and serological predictors of suicide in schizophrenia and major mood disorders

May 3, 2018
Dickerson, F., Origoni, A., Schweinfurth, L.A.B., Stallings, C., Savage, C.L.G., Sweeney, K., Katsafanas, E., Wilcox, H.C., Khushalani, S., Yolken, R.
Journal of Nervous and Mental Disease 2018; 206: 173-178

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Are infectious agents involved in the pathogenesis of postpartum psychosis?

May 3, 2018
de Witte, L.D., Snijders, G., Litjens, M., Kamperman, A.M., Kushner, S.A., Kahn, R.S., Bergink, V.
Journal of Affective Disorders 2018; 229: 141-144

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Toxoplasma gondii infection and behavioral outcomes in humans: a systematic review

February 12, 2018
Martinez, V. O. , Lima, F. W. D., . de Carvalho, C. F, Menezes, J. A.
Parasitology Research 2018; 117: 3059-3065

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Toxoplasma gondii exposure and the risk of attention deficit hyperactivity disorder in children and adolescents

February 12, 2018
Khademvatan, S. , Riahi,F., Izadi-Mazidi,M. , Khajeddin, N., Yousefi, E.
Pediatric Infectious Disease Journal 2018; 37: 1097-1100

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Is Toxoplasma gondii infection correlated with nonalcoholic fatty liver disease?- a population-based study

February 12, 2018
Huang, J. F. , Zhang, H. Y., Liu, S. Y. ,Wang, M. F. .Wan, B. , Velani, B. ., Zhu , Y. Y., Lin, S.
BMC Infectious Diseases 2018; 18: DOI: 10.1186/s12879-018-3547-1

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Immunoglobulin sub-class distribution in bipolar disorder and schizophrenia: potential relationship with latent Toxoplasma Gondii infection

February 12, 2018
Hamdani,N. ,Bengoufa, D. , Godin, O., Doukhan, R.., Le Guen,E., Daban-Huard, C. , Bennabi, M. ,Delavest, M., Lepine, J. P., Boukouaci, W. , Laouamri, H. , Houenou,J., Jamain, S., Richard,J. R. , Lecorvosier, P. , Yolken,R. , Rajagopal, K. , Leboyer, M. , Tamouza, R.
BMC Psychiatry,10.1186/s12888-018-1821-9, Article Number 239

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Latent toxoplasma infection in real-world schizophrenia: Results from the national FACE-SZ cohort

February 12, 2018
Fond,G., Boyer, L. ,Schurhoff, F. ., Berna,F. , Godin, O., Bulzacka, E., Andrianarisoa, M. Brunel, ,L. ,Aouizerate, B. , Capdevielle, D.,Chereau, I. , Coulon, N., D'Amato, T. , Dubertret,C. , Dubreucq, J.,Faget, C.,. Lancon, Leignier,S., Mallet,J., Misdrahi, D., Passerieux, C., Rey,R., Schandrin,A., Urbach,M., Vidailhet,P., Llorca, P. M., Leboyer, M., Grp,F.S.
Schizophrenia Research 2018; 201: 373-380

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Objective: Latent Toxoplasma infection has been associated with widespread brain immune activation, increased blood brain barrier permeability, neural disruption, increased dopamine release in dopaminergic neurons, with NMDA activation and with schizophrenia (SZ) onset risk. Toxoplasma has been suggested to be a source of chronic low-grade inflammation and this inflammation has been associated with cognitive impairment in SZ. The objective of the present study were (i) to determine if latent Toxoplasma infection was associated with specific clinical features in stabilized SZ subjects, with cognitive impairment and with increased low-grade peripheral inflammation and (ii) to determine if Treatments with Anti-Toxoplasmic Activity (TATA) were associated with improved outcomes in subjects with latent Toxoplasma infection. Methods: A comprehensive 2 daylong clinical and neuropsychological battery was administered in 250 SZ subjects included between 2015 and 2017 in the national FondaMental Expert Center (FACE-SZ) Cohort. Solid phase-enzyme microplate immunoassay methods were used to measure IgG class of antibodies to T. gondii in blood sample. Latent Toxoplasma infection was defined by T. gondii IgG ratio >= 0.8, equivalent to >= 10 international units. Chronic peripheral inflammation was defined by highly sensitive Creactive protein blood level >= 3 mg/L. Results: Latent Toxoplasma infection has been found in 184 (73.6%) of this national multicentric sample. In the multivariate analyses, latent Toxoplasma infection has been significantly associated with higher PANSS negative (aOR = 1.1 [1.1-1.1], p = 0.04) and excitement subscores (aOR = 1.3 [1.1-1.6], p = 0.01), with two specific symptoms (i.e., reference delusion (aOR = 3.6 [1.2-10.6] p = 0.01) and alogia (aOR = 16.7 [2.0-134.7], p = 0.008)) and with chronic low-grade peripheral inflammation (27.2% vs. 7.6%, aOR = 3.8 [1.4-10.3], p = 0.004). Extrapyramidal symptoms remained significantly associated with latent Toxoplasma infection. On the opposite, no significant association of latent Toxoplasma infection with age, gender, age at SZ onset, suicide behavior or cognitive deficits has been found in these models (all p > 0.05). TATA were associated with lower depressive symptoms (aOR = 0.8[0.7-0.9], p = 0.01), and with lower rates of chronic peripheral inflammation (20.9% vs. 48.6%, aOR = 3.5 [1.5-7.9], p = 0.003) but not with higher cognitive scores (p > 0.05). Conclusion: The present findings suggest that Toxoplasma is almost 3 times more frequent in SZ population compared to general population in France. The potential cerebral underpinnings of the association of latent Toxoplasma infection and the above-mentioned outcomes have been discussed. Future studies should confirm that TATA may be effective to reduce Toxoplasma-associated depressive symptoms and low-grade peripheral inflammation.

Toxoplasmosis, but not borreliosis, is associated with psychiatric disorders and symptoms MENTAL

February 12, 2018
Flegr, J., Horáček, J.
Schizophrenia Research 2018; 197: 603-604

Toxoplasma gondii seropositivity and substance use in US adults

February 12, 2018
Berrett, A. N., Gale, S. D., Erickson,L. D., Thacker, E. L., Brown, B. L., Hedges, D. W.
Folia Parasitologica 2018; 65: 011

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Toxoplasmosis, the insidious parasitic infection: dangers of asymptomatic carrier state

December 8, 2017
Bognar, L., Izso, T., Szakos, D., Kasza, G.
Magyar Allatorvosok Lapja 2017;139:479-487

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Background: The highly prevalent parasitic infection of humans, toxoplasmosis, can have serious consequences even during an asymptomatic course of the disease. The causative agente of infection is Toxoplasma gondii, which proliferates in the intestine of cats. Risk of infection by direct contact with cats is low, but the infection can occur due to contaminated soil, water, unwashed vegetables and fruits, as well as insufficiently heat-treated meat. Objectives: The aim of this study was to synthesize the current knowledge about infection caused by Toxoplasma gondii in a brief review focusing on latent toxoplasmosis in humans. Materials and Methods: More than hundred articles, studies and reports from scientific journals were considered to summarize the infection's characteristics such as prevalence and symptoms in humans. Results and Discussion: The symptoms of acute toxoplasmosis are either featureless, or non-existent, although, for people with immunosuppression it can be fatal, and for expectants it can result in foetal harm. The detection of the infection is conducted with serology methods, however, only in a few European countries are general screenings present. The asymptomatic carrier state is dangerous as well, because the cysts subsist in the brain of the host, which affects behaviour, the regulation of emotions, and also the level of several hormones. The latent toxoplasmosis can be connected to aggression, anxiety, schizophrenia, bipolar personality disorder, suicidal inclination, depression, and the reduction in intelligence quotient. For the reason of the deterioration of reaction time, the disease increases the risk of traffic accidents. The latent toxoplasmosis also influences personality traits; for women and men the alteration of the personality change differs. There is no data on the current epidemiological situation in Hungary, and not even in Europe. A research regarding the extent of asymptomatic carrier state and about the psychological changes in the Hungarian population has not been conducted so far.

Association of Toxoplasma gondii infection with schizophrenia and its relationship with suicide attempts in these patients

December 8, 2017
Ansari-Lari, M., Farashbandi, H., Mohammadi, F.
Tropical Medicine and International Health 2017; 22: 1322-1327

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Fetomaternal and pediatric toxoplasmosis

December 6, 2017
Oz, H. S.
Journal of Pediatric Infectious Diseases 2017; 12: 202-208

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New, previously unreported correlations between latent Toxoplasma gondii infection and excessive ethanol consumption

December 6, 2017
Samojlowicz, D., Borowska-Solonynko, A., Kruczyk, M.
Forensic Science International 2017; 280: 49-54

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A number of world literature reports indicate that a latent Toxoplasma gondii infection leads to development of central nervous system disorders, which in turn may lead to altered behavior in the affected individuals. T. gondii infection has been observed to play the greatest role in drivers, suicides, and psychiatric patients. Studies conducted for this manuscript involve a different, never before really reported correlation between latent T. gondii infection and ethanol abuse. A total of 538 decedents with a known cause of death were included in the study. These individuals were divided into three groups: the risky behavior group, inconclusively risky behavior group, and control group. The criterion for this division was the likely effect of the individual's behavior on the mechanism and cause of his/her death. The material used for analyses were blood samples collected during routine medico-legal examinations in these cases. The blood samples were used to measure anti-T. gondii IgG antibodies with an enzyme-linked immunosorbent assay (ELISA). Moreover, the following data were recorded for each decedent: sex, age, circumstances of death, cause of death, time from death to autopsy, and (if provided) substance abuse status (alcohol, illicit drugs). In those cases where blood alcohol level or toxicology tests were requested by the Prosecutor's Office, their results were also included in our analysis. Test results demonstrated a strong correlation between latent T. gondii infection and engaging in risky behaviors leading to death. Moreover, analyses demonstrated a positive correlation between the presence of anti-T. gondii IgG antibodies and psychoactive substance (especially ethanol) abuse, however, the causal relationship remains unclear. Due to the fact that alcohol abuse constitutes a significant social problem, searching for eliminable risk factors for addiction is extremely important. Our analyses provided new important information on the possible effects of latent T. gondii infection in humans.

Parkinson’s disease and Toxoplasma gondii infection: Sero-molecular assess the possible link among patients

October 2, 2017
Fallahi, S., Rostami, A., Birjandi, M., Zebardast, N., Kheirandish, F., Spotin, A.
Acta Tropica 2017; 173: 97-101

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Toxoplasma gondii and schizophrenia: a review of published RCTs

October 2, 2017
Chorlton, S.D.
Parasitology Research 2017; 116: 1793-1799

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The association between Toxoplasma and the psychosis continuum in a general population setting

October 2, 2017
Lindgren, M., Torniainen-Holm, M., Yolken, R., Suvisaari, J.
Schizophrenia Bulletin 2017; 43: S108-S109

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Background: An increased prevalence of antibodies to Toxoplasma gondii has been found to be associated with psychosis. An association with positive symptom severity in a psychosis risk sample has also been reported. However, the possible association between toxoplasma and positive symptoms in the general population is unknown. Methods: We investigated whether Toxoplasma gondii is associated with psychosis diagnoses and psychotic symptoms in the general population. We used data from Health 2000, a large health survey of the Finnish population aged 30 and older (n = 5906). Levels of IgG antibodies to Toxoplasma gondii were determined and seropositivity defined as a cutoff of 50 IU/ml. Lifetime psychotic symptoms were identified with section G of the Composite International Diagnostic Interview, Munich version (M-CIDI). The CIDI screen was considered positive if the interviewee reported any clinically relevant symptom or at least 3 symptoms regardless of clinical relevance. Lifetime psychotic disorders were screened from the sample and were diagnosed with DSM-IV using case notes and SCID-I interview. The possible diagnoses were: any psychotic disorder, functional psychosis, schizophrenia, other nonaffective psychosis, and affective psychosis. Results: The seroprevalence of Toxoplasma in the population was 13%; 12% of the participants reported at least one psychotic symptom, the most common symptoms being delusions of reference and suspicion, and 4% were considered positive for the CIDI screen. In a logistic regression model, toxoplasma seropositivity was the only significant predictor of the CIDI screen status, when other variables associated with toxoplasma were adjusted for (age, gender, education, region of residence, cat ownership, and C-reactive protein measuring inflammation). Toxoplasma infection was not associated with any psychosis diagnoses. Conclusion: In a large sample representing the whole Finnish population aged 30 and older, we found that toxoplasma infection predicted psychotic symptoms but not psychosis diagnoses. The association between psychotic symptoms and toxoplasma was not explained by inflammation.

From toxoplasmosis to schizophrenia via nMda dysfunction: peptide overlap between Toxoplasma gondii and N-Methyl-D-aspartate receptors as a potential Mechanistic Link.

October 2, 2017
Lucchese, G.
Frontiers in Psychiatry 2017; 8

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Relationship between Toxoplasma gondii seropositivity and acoustic startle response in an inner-city population

October 2, 2017
Massa, N. M., Duncan, E., Jovanovic, T., Kerley, K., Weng, L., Gensler, L., Lee, S. S., Norrholm, S., Powers, A., Almli, L. M., Gillespie, C. F., Ressler, K., Pearce, B. D.,
Brain Behavior and Immunity 2017; 61: 176-183

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Toxoplasma gondii (TOXO) is a neuroinvasive protozoan parasite that induces the formation of persistent cysts in mammalian brains. It infects approximately 1.1 million people in the United States annually. Latent TOXO infection is implicated in the etiology of psychiatric disorders, especially schizophrenia (SCZ), and has been correlated with modestly impaired cognition. The acoustic startle response (ASR) is a reflex seen in all mammals. It is mediated by a simple subcortical circuit, and provides an indicator of neural function. We previously reported the association of TOXO with slowed acoustic startle latency, an index of neural processing speed, in a sample of schizophrenia and healthy control subjects. The alterations in neurobiology with TOXO latent infection may not be specific to schizophrenia. Therefore we examined TOXO in relation to acoustic startle in an urban, predominately African American, population with mixed psychiatric diagnoses, and healthy controls. Physiological and diagnostic data along with blood samples were collected from 364 outpatients treated at an inner-city hospital. TOXO status was determined with an ELISA assay for TOXO-specific IgG. A discrete titer was calculated based on standard cut-points as an indicator of seropositivity, and the TOXO-specific IgG concentration served as serointensity. A series of linear regression models were used to assess the association of TOXO seropositivity and serointensity with ASR magnitude and latency in models adjusting for demographics and psychiatric diagnoses (PTSD, major depression, schizophrenia, psychosis, substance abuse). ASR magnitude was 11.5% higher in TOXO seropositive subjects compared to seronegative individuals (p = 0.01). This effect was more pronounced in models with TOXO serointensity that adjusted for sociodemographic covariates (F = 7.41, p = 0.0068; F = 10.05, p = 0.0017), and remained significant when psychiatric diagnoses were stepped into the models. TOXO showed no association with startle latency (t = 0.49, p = 0.63) in an unadjusted model, nor was TOXO associated with latency in models that included demographic factors. After stepping in individual psychiatric disorders, we found a significant association of latency with a diagnosis of PTSD (F = 5.15, p = 0.024), but no other psychiatric diagnoses, such that subjects with PTSD had longer startle latency. The mechanism by which TOXO infection is associated with high startle magnitude is not known, but possible mechanisms include TOXO cyst burden in the brain, parasite recrudescence, or molecular mimicry of a host epitope by TOXO. Future studies will focus on the neurobiology underlying the effects of latent TOXO infection as a potential inroad to the development of novel treatment targets for psychiatric disease.

Prevalence of Toxoplasma infection in first episode schizophrenia and bipolar disorder: Comparison between Toxoplasma seropositive and Toxoplasma seronegative groups.

October 2, 2017
Solanki, R.K., Singh, C., Mishra, V.
Indian Journal of Psychiatry 2017; 59: S212-S212

Curiosity killed the cat: no evidence of an association between cat ownership and psychotic symptoms at ages 13 and 18 years in a UK general population cohort

May 9, 2017
Solmi, F., Hayes, J.F., Lewis, G., Kirkbride, J.B.
Psychological Medicine 2017; 47: 1659-1667

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