Abstract
This lecture has attempted to make sense of the chronic, more or less latent presence of numerous viral species and genotypes in humans. What is now commonly referred to as the virome remains largely an enigma when it comes to understanding the logic of its co-evolution with the human species. The digestive tract, skin, immune system, nervous system and liver are the major tissues known to host viruses in a latent mode, possibly subject to recurrence. Many of these viruses are contracted very early in life (Anellovirus, non-oncogenic Papillomaviruses) and, in the absence of demonstrable pathogenicity, we may wonder what is the meaning of this chronic parasitism and to what extent, like the bacterial microbiome, this virome could play a role in the development, maturation and health or disease of the individual. For other pathogenic viruses such as Herpesviruses (HSV, CMV, Epstein-Barr), beyond the immediate pathogenicity of the primary infection and frequent recurrences after their entry into latency, the question arises as to whether they can collectively have a beneficial effect on the maturation of the immune system in children, and a deleterious effect influencing the senescence of immune effector cells in the elderly.
