The relegation-threatened team played Tottenham on Sunday before the north London club announced a coronavirus outbreak among players and staff that has forced the postponement of two games.
Two Norwich players have undergone additional COVID-19 testing, though Smith said he doesn't think the scare stems from the Tottenham match. They were awaiting test results as they prepare to host United on Saturday.
``The couple of players who we are worried about have been tested,'' Smith said. ``It is not likely to be related to the game at Tottenham Hotspur as our first round of testing was all clear, but the players are all aware of the importance of looking after each other, social distancing and wearing masks.''
The players, who were not identified, had been feeling ``a little bit unwell,'' the manager said.
Tottenham's outbreak _ eight players and five members of staff had tested positive _ forced the postponement of the club's Europa Conference League match Thursday against French team Rennes and its Premier League game at Brighton on Sunday. Tottenham's training center was closed as a precaution.
Britain this week announced tighter restrictions to stem the spread of the omicron variant, urging people in England to again work from home and mandating COVID-19 passes for entrance into nightclubs and large events.
Aston Villa chief executive Christian Purslow plans to visit the club on Monday to talk to players about staying safe, manager Steven Gerrard said Friday.
``We've always remained very safe around the facilities, we've always stuck to a certain level of ruling to protect ourselves and protect each other,'' Gerrard said at a press conference ahead of Saturday's game at Liverpool. ``But we have obviously been told and warned that things are changing all the time and just to be careful.''
The former Liverpool great acknowledged ``you've always got that little lingering paranoia about the what-ifs. And it is a virus that's not gone, we're not through the woods.
``And it's changing all the time,'' Gerrard added, ``so you've always got to be on your toes and be as careful as you can because you don't want to be in a situation where you're losing players, which obviously affects points.''
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