Seroprevalence of toxoplasma gondii in healthy blood donors at eastern zone blood transfusion services (ezbts) in Dar es salaam, Tanzania 2011

Abstract

Background: Blood transfusion services are required to provide blood and blood derived components which are safe in a cost effective way for transfusion into patients who require the blood products. Blood donation tends to save lives for many people but posses many challenges particularly when it comes to screening. Some blood donation centres routinely screen only limited number of infectious agents. EZBTS for example screen for HIV, Hepatitis B, Hepatitis C and Syphilis only. However, T. gondii infections in blood donors represent a risk of transmission of the pathogens to the recipients. There is scarce information about the prevalence of T. gondii in blood donors in Tanzania. A number of studies have shown that the risk for T. gondii infection increases with age but the difference was not significant between genders. Study objective: The aim of this study was to determine the prevalence of T. gondii infection among healthy donors in Dar es Salaam and possible implications on mandatory T. gondii screening. Methodology: A cross-sectional study was conducted at the EZBTS located at Ilala District, in Dar es Salaam City. One hundred and sixty donated blood samples were examined for T .gondii infection between November 2011 and April 2012. Donated blood was tested for anti-T. gondii IgG and IgM antibodies by using ELISA. Results: Seventy six (76) of 160 donated blood tested positively for IgG anti-T. gondii antibodies. None of the blood donors tested positive for IgM anti-T .gondii antibodies. In this study 108 (67.5%) male tested positive for IgG anti-T. gondii and 52 (32.5%) female were IgG positive. The study found that the percentage IgG positive (seroprevalence) was much higher in male than female although the difference was not significant. (p=0.112) Moreover, we observed that the frequency of seropositivity decreased with advancing age from 45-54 years and above. The highest peak for percentage IgG positive (41.2%) were in the age range of 25 to 34 years. The seroprevalence in the age of 25-34 was influenced by age, since the association was statistically significant (p= 0.001). The Skilled category (non-labourers) had higher percentage IgG seroprevalence (61.2%) while the lowest was unskilled category (labourers) (15.2%). We observed that the association was statistically significant (p= 0.024). Based on area of domicile, Temeke district has shown to have a higher percentage IgG seroprevalence while the lowest was Ilala district. The seroprevalence was not influenced by area of domicile, since the association was not statistically significant (p= 0.101) Conclusion: This study revealed high prevalence of T. gondii among blood donors, indicating potential hazard for blood transfusion and highlighting the importance of screening for T. gondii among blood donors. The disease toxoplasmosis should be considered to be included in pre transfusion testing schedule together with other tests i.e HIV, Hepatitis B, hepatitis C and Syphilis.