HIV is classified in the family Retroviridae, subfamily Lentivirinae,
and genus Lentivirus.1,2,3 The structure of HIV follows the
typical pattern of the retrovirus family, comprising a singlestranded, positive-sense ribonucleic acid (RNA) genome of
about 9.7 kilobases. There are two strands of HIV RNA and each
strand has a copy of the virus’s nine genes (Figure 1.1a). The
RNA is surrounded by a cone-shaped capsid which consists of
approximately 2000 copies of the p24 viral protein. Surrounding
the capsid is the viral envelope. The viral envelope is composed
of a lipid bilayer membrane, formed from the cellular membrane of the host cell during budding of the newly formed virus
particle