Yu isn't going to be infected; he'll keep on being that shining beacon of Hope that he always is.

He's mostly going to have his hands full trying to look after Dojima and Adachi, but he'll be out to help the infected. It's very likely he'll be eating sparsely and spending the majority of any prize cards he gets to get food and cure phials.

If anyone would like him to help their character, let me know. I'm also open to characters being resistant to his help as well, to the point of potentially hurting him.