Prevalence of Toxoplasma gondii Infection among Healthy Blood Donors in Northeast of Iran

Background This cross-sectional investigation aimed to evaluate the prevalence of IgM and IgG anti-Toxoplasma gondii antibodies and the associated risk factors among healthy blood donors in Khorasan Razavi Province, northeast of Iran from Nov 2014 to May 2015. Methods Overall, 491 serum samples from apparently healthy blood donors referred the six biggest blood centers in Razavi Khorasan, Iran, were screened for IgG and IgM anti-T. gondii antibodies by enzyme-linked immunosorbent assay (ELISA). A structured questionnaire was used to obtain information on risk factors for T. gondii infection. Nested PCR was also used to detect DNA of T. gondii in the IgM-positive samples by using of B1 and RE (Repetitive Element) as marker for amplifying fragment size of 531 bp and 164 bp in PCR method. Results Totally, 200 (40.7%) samples were seropositive for anti-T. gondii antibodies; 184 (37.5%) donors tested seropositive for only IgG antibody, 8 (1.6%) tested seropositive for both IgM and IgG and 8 (1.6%) were positive for IgM antibody alone. Several risk factors significantly related to T. gondii seropositivity in the univariate analysis at P<0.05 included age (P<0.001), and raw/half-cocked meat consumption (P=0.015). T. gondii DNA was found in all sixteen IgM-positive samples. Conclusion T. gondii infection was present among healthy blood donors in northeast of Iran. Thus, it is suggested to design screening programs for preventing transfusion-transmitted toxoplasmosis.