In order to assess if HTLV-1 retrovirus had penetrated in a group of sailors that often travel to endemic areas for HTLV-1 infection (West coast of sub-Saharan Africa) we have performed the following study. A total of 499 sera samples from sailors traveling to Africa during the last five years were studied. The presence of HTLV-1 antibodies was determined using an enzyme-linked immunosorbent assay (ELISA, Dupont HTLV-1). Positive ELISA test results were further confirmed using a Western blot technique. In all patients the presence of HIV-1 and HIV-2 antibodies was also tested using ELISA and Western blot techniques. Using ELISA we find 7 positive sera to HTLV-1 (1.4%) but only one sera sample (0.2%) was also positive by Western blot analysis. We conclude that HTLV-1 infection is entering a population group traveling to endemic areas. The possibility of heterosexual transmission of the virus in our environment has to be taken into account.