Sexual transmission via oral routes has been reported, but is probably extremely infrequent. The biological mechanism underlying the sexual transmission of HIV is not completely understood. In particular, the question of whether the mucosal epithelium is directly infected or whether infection traverses the epithelium to underlying lymphoid cells needs to be answered. Vertical transmission of HIV can occur antenatally, perinatally and perhaps following birth through breastfeeding. Transmission occurs in 20 to 30 percent of births to infected mothers.
Most transmission appears to occur perinatally.
Maternal viral load is the major factor associated with transmission. Administration of anti-viral drugs to infected mothers may significantly reduce mother to child transmission. The question of whether these viruses are more infectious has not been determined. Diagnosis Laboratory diagnosis of HIV infection is performed by testing for anti-HIV antibody. Confirmation is critical, since false positives can occur.