HTLV-1 is a blood-borne and sexually transmissible virus that can be transmitted through infected body fluids, via condom-less sexual intercourse (10-13), breastfeeding (14-17), sharing of injection equipment (18-21), blood transfusion (22, 23) and transplantation of infected organs (24-28). As with most blood-borne/sexually transmissible viruses, most people with HTLV-1 infection transmit the virus unknowingly and are unaware that they are at risk of developing HTLV-1 diseases.  Data from Central Australia (9), Japan (29) and Brazil (13, 30) show the importance of the sexual transmission of HTLV-1. The sexual transmission of HTLV-1 was also highlighted in several presentations at the 18th International Retrovirology Conference in Tokyo, Japan in March 2017 (29) and at the 2017 Australasian HIV & AIDS and Sexual Health Conference in Canberra, Australia (31). Worldwide, it is mostly women who carry the burden of HTLV-1 infection and its associated diseases.  They become infected through condom-less sex and can unknowingly transmit the infection to their babies through breastfeeding. Therefore, HTLV-1 is highly concentrated in families [1:3 to 1:4 of family contacts can carry the virus (32, 33)].