Just include the following elements – just write the introduction ONLY:
start with generalities about HIV-1 and HIV-2. Explain that AIDS is mostly caused by HIV-1 and that people who are infected can be treated, but because of latency they cannot be cured. Then explain the history of HIV-2 as a passage from smaller monkeys to humans and how it became HIV-2. Explain that little is known about HIV-2 in general because people are not as sick as for HIV-1, but that for understanding the mechanisms of infection, it is equally important as HIV-1.