Epidemiology of Toxoplasma gondii among blood donors in Iran: A systematic review and meta-analysis.

INTRODUCTION: Asymptomatic Toxoplasma gondii transmitted from blood donors to receiving patients has become a concern. Numerous articles have been published on the epidemiology of T. gondii in blood donors in Iran and a systematic review of the results shows quite different findings, hence this study was conducted to determine the seroprevalence of T. gondii in Iranian blood donors using meta-analysis.

METHODS: We searched for epidemiological studies that were published until July 2016 in eight English databases including: Scopus, PubMed, Ovid, Science Direct, Cochrane, Web of Science, Springer, Wiley Online Library, and four Iranian databases: Magiran, Iranmedex, SID and Medlib as well as Google Scholar. To estimate pooled estimator, regarding high heterogeneity and significance of I2 index, Random effects model was used. Data analysis was conducted using Review Manager Ver5.3.5 and P<0.05 was considered significant.

RESULTS: Among 10 studies with a sample size of 4538 Iranian blood donors, the seroprevalence of T. gondii was calculated to be 34.4% (CI95%: 24.9-43.9). The rate in males and females was 33.36% (CI95%: 19.92-46.81) and 37.63% (CI95%: 20.81-54.45), respectively. The seroprevalence of IgM and IgG antibodies among blood donors were 2.74% (CI95%: 0.55-4.92) and 31.84% (CI95%: 20.61-43.08), respectively. The seroprevalence of T. gondii was significantly associated regarding blood group (P=0.04), but this relation was not significant with blood transfusion (P=0.62).

CONCLUSION: The results of this review indicate a high seroprevalence of T. gondii (about one-third) in Iranian blood donors and emphasizes the importance of screening the seroprevalence of T. gondii of donated blood in Iranian Blood Transfusion Organization.