10^6-10^7 cells should suffice. The more the confluency the better. However, in my experience, 100% confluency does not help. Growing cells to about 90% confluence is the best time for viral infections.

I agree with Adhiraj

Hi Bruce Lyday ,

Though it depends on the size of the cells but you mentioned 96 well plate so the size of the well is short here.

So, you must try with less number of cells 10^4-10^5 cells/well.

Keep sharing your experience too.....

Thanks and Good luck