This is a timeline of HIV/AIDS, including but not limited to cases before 1980. Researchers estimate that some time in the early 20th century, a form of
HIV/AIDS originated in the early 20th century and has become a major public health concern and cause of death in many countries. AIDS rates vary significantly
population of persons with HIV/AIDS (as of 2023[update], with SouthAfrica and Nigeria having more), the AIDS prevalence rate in India is lower than that