Poke Virus

[Da Champion]

Need some help understading this cause it wasn't well explained to me.
1. Does work better during or after?
2.What Lv should it be used Early forms or Later?

[Cytosine]

1) Doesn't really matter, but afterwards you can't spread it to other pokemon.
2) It's better while you're EV training, therefore, at lower levels so you still have EVs to gain.

[Da Champion]

OK thnks