Current toxoplasmosis tests: toxoplasma gondi igg avidity 0.78 (high) toxoplasma ab igm 3.0, toxo pcr negative. in 2021 lost some vision. told toxo reactivation w/ab igg 400, (high), no previous toxo diagnosis. what does this mean? reactivation?

It means you were exposed to T. gondii and had infection at some point probably from exposure to cats. The body was able to fight the infection but the T. gondii usually persists in the body with adequate containment by the immune cells. Aging or other things like stress, steroid, other infections and other medications could lower immunity and allow the T. gondii to multiply and cause disease.