Intrafamilial Transmission of HTLV-1 and HTLV-2 in Indigenous Peoples of the Brazilian Amazon: Molecular Characterization and Phylogenetic Analysis.

Human T-limphotropic virus 1 infection has a global distribution, with a high prevalence in some regions of Brazil and the world, while HTLV-2 infection is endemic mainly among indigenous people and drug users. To analyze intrafamilial transmission of HTLV-1/2 in five Kayapó indigenous peoples (Gorotire, Kararaô, Kokraimoro, Kubenkokre, and Xikrin do Bacajá), we investigated 1452 individuals who underwent serological and molecular tests. Among the 276 indigenous people with positive results, we identified intrafamily transmission in 42.

HTLV in South America: Origins of a silent ancient human infection.

The description of the first human retrovirus, human T-lymphotropic virus 1 (HTLV-1), was soon associated with an aggressive lymphoma and a chronic inflammatory neurodegenerative disease. Later, other associated clinical manifestations were described, affecting diverse target organs in the human body and showing the enormous burden carried by the virus and the associated diseases. The epidemiology of HTLV-1 and HTLV-2 showed that they were largely distributed around the world, although it is possible to locate geographical areas with pockets of low and very high prevalence and incidence.