Prevalence of Kaposi's sarcoma-associated herpesvirus and transfusion-transmissible infections in Tanzanian blood donors

Objective: Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent for Kaposi's sarcoma (KS), one of the most common cancers in Tanzania. We have investigated KSHV prevalence and factors associated with KSHV infection in Tanzania. Methods: This is a cross-sectional study of voluntary blood-donors from Dar es Salaam, Tanzania. Plasma was screened for KSHV, HIV-1, HBV, HCV and Treponema pallidum (syphilis). Associations between KSHV sero-status and risk factors were analyzed. Odds ratios (OR) and 95% confidence intervals (CI) are reported to evaluate risk factors of KSHV infection. All tests were 2-tailed, and P-values <0.05 were considered statistically significant. Results: The overall KSHV seroprevalence was 56.9%. Significantly increased risk of KSHV infection was detected in persons from the Lake and Central Zones (OR = 6.4, 95% CI = 1.6–25.3, P = 0.008 and OR = 5.7, 95% CI = 1.0–32.5, P = 0.048 respectively). A trend toward increased risk of KSHV infection with HIV-1 co-infection was not significant (OR = 2.8, 95% CI = 1.0–8.0, P = 0.06). Seroreactivity to T. pallidum was surprisingly high (14.9%). Conclusion: The prevalence of KSHV infection and syphilis was high among Tanzanian blood-donors. The most common transfusion-transmissible infections did not associate with KSHV infection. Regions of focal KSHV infection need further investigation for underappreciated risk factors.