Her health regen based off of targets affected by her trait seems really strong. She's got decent sustain for teamfights, especially with her targeted poison wave ult. Each damage tick is a heal over time.
It's not per target affected - it's just a small heal if you have someone affected. At level 20 it's 41 health per tick, which seems minuscule. At the same tier as the wave clear talent, which seems extremely strong - she demolished buildings faster than anyone it seems if she takes that.