Toxoplasma infection and Rhesus blood group system: A systematic review and meta-analysis

Abstract

Background Toxoplasmosis is one of the most common infections in humans and animals, which is caused by an obligate intracellular opportunistic parasite known as Toxoplasma gondii (T. gondii). Some data have shown that both Rhesus (Rh)-positive and Rh-negative individuals differ in response to biological factors, including Toxoplasma infection. Therefore, this systematic review and meta-analysis was conducted to investigate the scientific evidence regarding the possible association between the Rh blood group and Toxoplasma infection and to determine the seroprevalence of T. gondii in the Rh blood group system. Methods The research was conducted on PubMed, ScienceDirect, ProQuest, and Google Scholar databases until January 2023. Twenty-one cross-sectional studies were included with a total of 10910 people. The data were synthesized using a random effect model with 95% confidence intervals (CIs). Results The overall prevalence of T. gondii was calculated at 32.34% (CI 95%: 28.23–36.45%) and 33.35% (CI 95%: 19.73–46.96%) in Rh-positive and Rh-negative blood groups. In addition, the pooled OR for the relationship between the Rh blood group and the seroprevalence of T. gondii was 0.96 (95% CI: 0.72–1.28). Conclusions This meta-analysis showed a high prevalence of Toxoplasma infection in both Rh-negative and positive blood groups. This systematic review and meta-analysis revealed that no significant association was found between toxoplasmosis and Rh factor. Because of the limited number of studies in this field, more research is recommended to determine the exact relationship between toxoplasmosis and the Rh factor.

Association between ABO and Rh blood groups and Toxoplasma gondii infection: A cross sectional study

“…However, our results agree with those reported in a meta-analysis that included 10,910 people of 21 studies and showed that no significant association was found between anti- T. gondii antibodies and Rh blood group [ 24 ]. In such meta-analysis researchers studied individuals of 3 continents including Asia, Europe and Africa but there was no available data on America and Australia [ 26 ]. Blood group systems other than the ABO system have been assessed on their association with T. gondii infection.…”

A Review of Immunological and Neuropsychobehavioral Effects of Latent Toxoplasmosis on Humans

“…In other hand, higher testosterone levels in infected males may result to higher psychoticism and interpersonal sensitivity symptoms than non‐infected men [34, 68, 75]. Psychoticism was defined by Hans Eysenck, a German–British psychologist, as a personality type that is prone to take risks, might engage in anti‐social behaviours, impulsiveness or non‐conformist behaviour.…”

“…However, they may also exhibit a diminished responsiveness to motivational rewards, potentially due to an elevation in dopamine levels [85]. It is noteworthy that there is evidence indicating some behavioural personality traits differ between infected women and men [2, 72, 75, 83].…”

“…The T. gondii genome contains tyrosine hydroxylase and tryptophan hydroxylase that could potentially affect dopamine and serotonin biosynthesis [111, 128]. In addition, there is a relationship between dopamine and sex hormones, such as testosterone, both of which increase during LT [34, 75]. Influencing human personality, behaviour and cognition, and reducing the risk of certain psychological disorders [113, 129].…”

“…Additionally, the facial features of infected males are rated by women as more masculine and dominant [113]. These differences may be resulted from a higher concentration of testosterone [26, 75, 113].…”