HTLV testing in blood transfusion.

To improve the safety of the blood supply, HTLV screening of blood donations became mandatory in different countries. In Japan and in Europe, the majority of HTLV-infected donors are HTLV-1 whereas in the USA more than half of them are HTLV-II-positive. The prevalence of HTLV-infected donors is low in European Countries as is the rate of seroconversion. Consequently, to test donors only once would have a high efficiency. This procedure is already in use in certain countries. Furthermore, if the use of leucodepleted cell concentrates is generalized, the policies of HTLV screening will still be further modified.