The relation of secondary sex ratio and miscarriage history with Toxoplasma gondii infection
Shojaee, S.,Teimouri, A., Keshavarz, H., Azami, S. J., Nouri, S.
Bmc Infectious Diseases 2018; 18: 307
Click for abstract
Background: Toxoplasma gondii is a protozoan parasite with worldwide distribution, infecting a broad-range of humans and warm-blooded animals. In the current study, role of this parasite on secondary sex ratio and risk of miscarriage was investigated. Methods: In this cross-sectional study, 850 cord blood samples were collected in Tehran, Iran, 2014-2015. Enzyme-linked immunosorbent assay (ELISA) was used to assess anti-Toxoplasma IgG in samples. Information such as sex of the neonates and age, number of previous pregnancies and history of miscarriage of the mothers were recorded in questionnaires. Logistic regression analysis was used to assess the possible relationship between the latent toxoplasmosis and the highlighted parameters. Results: Logistic regression analysis showed that the odds of having a male neonate in seropositive women is nearly 64% higher than that in seronegative women (OR = 1.64, CI95 = 1.16-2.33, P = 0.005). The odds ratio of having male neonate increased to 2.10 (CI95 = 1.24-3.57, P = 0.006) in high-titer seropositive women, compared to that in seronegative control group. The odds of having a miscarriage history was approximately two and a half times greater in seropositive women than in seronegative ones (OR = 2.45, CI95 = 1.56-3.87, P < 0.001). The odds ratio of having miscarriage increased to 2.76 (CI95 = 1.61-4.73, P < <.001) in low-titer seropositive women, compared to that in seronegative control group. Conclusion: Results of the current study have shown that T. gondii infection affects secondary sex ratio in human offspring and can be addressed as one of the major miscarriage causes in women.
Can offspring sex ratios help to explain the endocrine effects of toxoplasmosis infection on human behaviour?
James, W. H., Grech, V.
Early Human Development 2018; 122: 42-44
Click for abstract
Humans infected with the parasite Toxoplasma gondii display a wide variety of abnormal behaviours, from suicide and depression to stuttering. These behaviours have been seen as so serious as to constitute a public health problem. It is not clear to what extent the parasite is a cause of, or merely a marker for, these behaviours, but there is evidence for both. Some of these behaviours are associated with changes in steroid hormones, that is, estrogen in women and testosterone in men. It is suggested here that these endocrine-related states of infected people may be better understood by studying their offspring sex ratios.
Does Toxoplasma gondii play a role in obsessive-compulsive disorder?
Taboas W, McKay D, Taylor S.
Psychiatry Research 2012; 198: 176-177
Toxoplasma gondii and other risk factors for schizophrenia: An update
Torrey, E.F., Bartko, J.J., Yolken, R.H.
Schizophrenia Bulletin 2012; 38: 642-647
Click for abstract
The failure to find genes of major effect in schizophrenia has refocused attention on nongenetic, including infectious factors. In a previous study, antibodies to Toxoplasma gondii were found to be elevated in 23 studies of schizophrenia (OR 2.73; 95% CI 2.10-3.60). The current study replicates this finding with 15 additional studies (OR 2.71; 95% CI 1.93-3.80) and compares this with other identified schizophrenia risk factors. The highest risk factors are having an affected mother (relative risks [RR] 9.31; 95% CI 7.24-11.96), father (RR 7.20; 95% CI 5.10-10.16), or sibling (RR 6.99; 95% CI 5.38-9.08) or being the offspring of immigrants from selected countries (RR 4.5; 95% CI 1.5-13.1). Intermediate risk factors, in addition to infection with T. gondii, include being an immigrant from and to selected countries (RR 2.7; 95% CI 2.3-3.2), being born in (RR 2.24; 95% CI 1.92-2.61) or raised in (RR 2.75; 95% CI 2.31-3.28) an urban area, cannabis use (OR 2.10-2.93; 95% CI 1.08-6.13), having minor physical anomalies (OR 2.23; 95% CI 1.42-3.58), or having a father 55 or older (OR 2.21-5.92; 95% CI 1.46-17.02). Low-risk factors include a history of traumatic brain injury (OR 1.65; 95% CI 1.17-2.32), sex abuse in childhood (OR 1.46; 95% CI 0.84-2.52), obstetrical complications (OR 1.29-1.38; 95% CI 1.00-1.84), having a father 45 or older (OR 1.21-1.66; 95% CI 1.09-2.01), specific genetic polymorphisms (OR 1.09-1.24; 95% CI 1.06-1.45), birth seasonality (OR 1.07-1.95; 95% CI 1.05-2.91), maternal exposure to influenza (RR 1.05; 95% CI 0.98-1.12), or prenatal stress (RR 0.98-1.00; 95% CI 0.85-1.16).
Relation of Schizophrenia Prevalence to Latitude, Climate, Fish Consumption, Infant Mortality, and Skin Color: A Role for Prenatal Vitamin D Deficiency and Infections?
Kinney, D. K., Teixeira, P., Hsu, D., Napoleon, S. C., Crowley, D. J., Miller, A., Hyman, W., Huang, E.
Schizophrenia Bulletin 2009; 35: 582-595
Click for abstract
Previous surveys found a large (> 10-fold) variation in schizophrenia prevalence at different geographic sites and a tendency for prevalence to increase with latitude. We conducted meta-analyses of prevalence studies to investigate whether these findings pointed to underlying etiologic factors in schizophrenia or were the result of methodological artifacts or the confounding of sites' latitude with level of healthcare at those sites. We found that these patterns were still present after controlling for an index of healthcare-025EFinfant mortality-025EFand focusing on 49 studies that used similar diagnostic and ascertainment methods. The tendencies for schizophrenia prevalence to increase with both latitude and colder climate were still large and significant and present on several continents. The increase in prevalence with latitude was greater for groups with low fish consumption, darker skin, and higher infant mortality-025EFconsistent with a role of prenatal vitamin D deficiency in schizophrenia. Previous research indicates that poor prenatal healthcare and nutrition increase risk for schizophrenia within the same region. These adverse conditions are more prevalent in developing countries concentrated near the equator, but schizophrenia prevalence is lowest at sites near the equator. This suggests that schizophrenia-producing environmental factors associated with higher latitude may be so powerful they overwhelm protective effects of better healthcare in industrialized countries. The observed patterns of correlations of risk factors with prevalence are consistent with an etiologic role for prenatal vitamin D deficiency and exposure to certain infectious diseases. Research to elucidate environmental factors that underlie variations in schizophrenia prevalence deserves high priority.
Low incidence of hypertensive disorders of pregnancy in women treated with spiramycin for toxoplasma infection
Todros, T., Verdiglione, P., Ogge, G., Paladini, D., Vergani, P., Cardaropoli, S.
British Journal of Clinical Pharmacology 2006; 61: 336-340
Click for abstract
Aims Toxoplasma infection in pregnancy is usually treated with long-term administration of the macrolide spiramycin to prevent fetal malformations. We had empirically observed that treated patients seldom developed pregnancy-induced hypertension (PIH), a common and severe disorder of pregnancy whose aetiology and pathogenesis are still debated. Some clinical and experimental data suggest that infection could play a role in its development. Methods To test this hypothesis, we studied a cohort of 417 pregnant women treated with spiramycin because of seroconversion for Toxoplasma gondii and 353 low-risk women who did not take any antibiotic during pregnancy. PIH was defined as blood pressure > 140/90 mmHg on two or more occasions, occurring after 20 weeks of gestational age. Results Seventeen (5.2%) women in the control group developed PIH compared with two (0.5%) in the case group. The odds of developing the disease were significantly lower in the treated subjects (odds ratio = 0.092, 95% confidence interval 0.021, 0.399; P < 0.001). Conclusions Our results suggest that antibiotic treatment during pregnancy can reduce the incidence of PIH, thus opening new perspectives in its prevention and therapy.