The first two components, the drugs AZT and 3TC, block the initial stages of HIV's reproductive process. To ensure that no viral genetic material can split and re-form at a later stage, a third set of drugs, known as protease inhibitors, is taken. Some of the drugs need to be taken on full stomachs, while others require fasting. If patients confuse this medication schedule, the infection level could rebound. The virus may even mutate into forms that are wholly drug-resistant.
Vaccines stop diseases by fooling the body.
They contain inactive viruses, in small doses. Even though the viruses usually cannot cause infection, inoculated individuals naturally defend themselves by building up antibodies. So when exposure to active viruses occurs, their systems are ready to fight off invaders. The virus also has several sub-strains, each one common to a specific region. In Hong Kong, HIV I is the most prevalent, while HIV E is found in Singapore and the Philippines.