Detection of HIV-1 provirus in HIV-1 seronegative individuals at risk has been described in several recent reports. Some of these sero-negative individuals remain so for prolonged periods, maybe for the rest of their lives. We do not know the significance of this finding and how it relates to pathogenesis and infectiousness. However, these persons seem to represent a minor group in the population. At present, these studies do not give valid reasons to change the Norwegian approach to the follow-up of persons at risk who have been tested and found HIV-antibody negative.