Greyson has guacamole in his diapersssssss

I got a call today from Greyson's daycare saying I had to come and get him. He'd had 2 loose stools. They said that some virus is going around and that they don't have it at their daycare yet and they are trying to keep from getting it there. The virus started with an S. It was a weird name. Anyway, Greyson's diarrhea is really bad and I don't know what to do about it. I can't bring him back to daycare until it's gone. So tomorrow I have to bring him to my sisters b/c I can't afford to take off anymore work. Does anyone know anything about this? Also, Greyson has never had diarrhea in his life. It is soooo bad. I am going through diapers like they're free.