Prevention of Human T-Cell Lymphotropic Virus Infection and Adult T-Cell Leukemia

Human T-cell lymphotropic virus type 1 was first discovered as a human retrovirus that causes the T cell hematological malignancy, called adult T cell leukemia/lymphoma[1, 2]. The virus is transmitted through contact with bodily fluids containing HTLV-1 infected cells mostly from mother to child transmission through breastfeeding or blood transfusion. ATLL occur after prolonged incubation periods. Strategies for the prevention of ATLL should be divided into two steps. The first step is the prevention of HTLV-1 transmission. This has been established in some HTLV-1 endemic areas by screening for HTLV-1 among blood donors and refraining from breastfeeding among pregnant women who are HTLV-1 carriers. The second step is the prevention of ATLL development among HTLV-1 carriers. This has not been established at all. Approximately 90% of HTLV-1 carriers remain as healthy as uninfected individuals through their lifetime and the risk factors for developing ATLL remain to be defined. In addition, preventative intervention like vaccination may cause other unfavorable immuno‐ logical consequences, thus well-examined strategies need to be further developed.