Genetic and epidemiological evidence of horizontal and vertical transmission of HTLV-I within a family in a low endemic area.

GASTALDELLO R; OTSUKI K; BARBÁS G; MATURANO E; PAULO VICENTE A; GALLEGO S

Congreso; 11th International Conference on Human Retrovirology: HTLV and Related Viruses.; 2003

Long periods of breast-feeding and sexual contact are considered to be important routes of transmission of Human T cell lymphotropic virus type I (HTLV-I) in low risk groups. However, genetic evidence supporting this observation has been lacking. In the North of Argentina, a high endemic area for HTLV-I, intrafamilial transmission of this virus has been observed. In this research we study the HTLV-I transmission in a low endemic area of the country. We investigated thirteen family members of a seropositive HTLV-I infected blood donor in order to determine their HTLV-I status. According to serological and molecular assays, four out of fourteen members of this family (the blood donor, the husband, a son and a daughter-in-law) proved HTLV-I positive. The complete identity of LTR and env sequences from the provirus infecting the family members and the epidemiological data confirmed, for the first time, HTLV-I intrafamilial transmission by means of breast-feeding and sexual contact in a low endemic area of Argentina.