Investigation of human T-cell lymphocytic leukemia virus infections among voluntary blood donors in Foshan City

Abstract

Objective To investigate the infection status of human T lymphocyte leukemia virus (HTLV) in voluntary blood donors in Foshan City of Guangdong Province, and to evaluate the risk of HTLV transmission through blood, in order to ensure safety of clinical blood transfusion in Foshan City. Methods From February to December 2016, a total of 69 275 blood donors in Foshan City were selected as study objects. Enzyme-linked immunosorbent assay(ELISA)was conducted to detect HTLV-Ⅰ/-Ⅱ antibodies in plasma from all blood donors, then reactivity samples were double-hole re-examined. The samples which were reactive by double-hole re-examined were determined primary screening results of HTLV-Ⅰ/-Ⅱ antibodies positive. And finally confirmed by Western blotting detection. The primary screening positive rates of HTLV-Ⅰ/-Ⅱ antibodies of blood donors from different gender, age, education degrees, household registration and times of blood donation were measured and compared by statistical method. Results ① In these 69 275 blood donors, HTLV-Ⅰ/-Ⅱ antibodies of 17 donors were positive, and primary screening positive rate of HTLV-Ⅰ/-Ⅱ antibodies was 0.025%. Among them, only 2 samples were identified as positive for HTLV-Ⅰ/-Ⅱ antibodies by Western blotting, and confirmed positive rate was 0.003%. ② The primary screening positive rate of HTLV-Ⅰ/-Ⅱ antibodies in female donors was 0.042% (11/26 291), which was higher than that of male donors (0.014%, 6/42 984) , and the difference was statistically significant (χ2=5.17, P=0.023). The primary screening positive rate of HTLV-Ⅰ/-Ⅱ antibodies in 46-55 years old blood donors was the highest as 0.084% (4/4 768) among donors of different ages, and the total difference of HTLV-Ⅰ/-Ⅱ antibodies primary screening positive rates in donors of different ages was statistically significant (χ2=8.09, P= 0.044). The blood donors with junior middle school education or below has the highest primary screening positive rate of HTLV-Ⅰ/-Ⅱ antibodies (0.063%, 7/11 113) among donors of different education degrees, and the total difference of primary screening positive rates was statistically significant (χ2=7.97, P=0.047). The primary screening positive rate of HTLV-Ⅰ/-Ⅱ antibodies in nonlocal registered blood donors (0.033%, 15/45 274) was higher than that of local registered donors (0.008%, 2/24 001), and the difference was statistically significant (χ2=3.93, P=0.047). The primary screening positive rate of HTLV-Ⅰ/-Ⅱ antibodies in multipe blood donors (0.034%, 16/46 414) who donated blood twice or more, was higher than that of the first blood donors (0.004%, 1/22 861), and the difference was statistically significant (χ2=5.65, P=0.017). Conclusions The results show that Foshan City belongs to low-incidence or non-endemic area of HTLV infection among voluntary blood donors. The risk of infection with HTLV was higher among female, elderly, low education, nonlocal registered and multipe blood donors. In view of blood transfusion safety, it is recommended that HTLV-Ⅰ/-Ⅱ antibodies of all voluntary donors should be detected before blood donation, and the blood should deal with filter to remove white blood cells. Key words: HTLV-Ⅰantibodies; HTLV-Ⅱ antibodies; Blood donors; Enzyme-linked immunosorbent assay; Blotting, Western; Blood safety