What is the average life expectancy of a person with fullblown aids?

Depends: It is always difficult to determine life expectancy of anyone with any type of chronic illness like hiv/aids. There are very good anti-hiv medications, which can extend life. Many of my patients who have had full-blown aids are still living 20+ years, but some have also died soon after diagnosis. It ultimately depends on one's immune system and how quickly they can recover before getting sick.