Hello,,

This is a low priority 'FMI' question, so please answer those more in need first, however, I am wondering how a long term nonprogressor is defined.. for example do the CD4 Cells stay normal and they have no symptoms, or do they fall to a stable level(thus they may have some symptoms, but not OIs) and remain constant..or is it the fact that their immune system maintains the viral load at a managable level? Is non-progression a natural immunity to the virus or simply a delay in progress(ie, AIDS without meds is inevitable), and if there are individuals with immunity why are scientists still playing with baboons when these people, it seems (to the medically ignorant such as myself) surely must hold the key to the cure. Thanks.

A classic long-term non-progressor has normal CD4 cells, undetectable virus and is clinically well despite having been infected with HIV years and years ago. It isn't entirley clear why this is so-- it may be that they have a stronger immune system and/or a weaker virus than other people. There are LTNPs who have been infected for more than 15 years who have still not gotten sick, so it seems unlikely that they ever will, although clearly that cannot be proven at this point in time.

LTNPs have been and continue to be intensively studied, but there are no clear definitive answers yet.