"Wash your hands a lot," Weiss said. "That's pretty much what we're doing. There's not a whole lot you can do. We're in a confined area. We spend a lot of time together, flying on the plane. It's not a lot you can do when you get a nasty bug like this it tends to go through the clubhouse.
"We've got a lot of guys feeling under the weather, not necessarily at the level of Wilin and Josh. We've got a few different bugs running around in that clubhouse."
Weiss said multiple players will come down with the same illnesses during a season, but not at the level of this one, which presents with the fever, headaches and body aches that come with the flu.
Are flu shots as a club policy the answer for a club?
"I know I do, but we've never mandated it for the team or anything like that," Weiss said.
The Rockies filled the roster spot by activating Sunday afternoon's starting pitcher, right-hander Jhoulys Chacin. Michael McKenry was called up Saturday to bolster the catching. He was in Sunday's starting lineup.
Thomas Harding is a reporter for MLB.com. Follow him on Twitter @harding_at_mlb. This story was not subject to the approval of Major League Baseball or its clubs.