A virus outbreak at Chelsea has prompted the club to hold a meeting with players on Thursday morning, reminding them about fundamental hygiene practices such as handwashing.
The illness has already claimed several victims, with Liam Delap and Jamie Gittens both forced to sit out Wednesday's Carabao Cup defeat to Arsenal after falling unwell.
The pair were described as suffering from "dangerously high temperatures" and remain at home as they attempt to recover ahead of Saturday's Premier League fixture against Brentford.
Staff members have also been affected by the outbreak overnight, with new head coach Liam Rosenior eager to prevent further casualties before the weekend's match.
Rosenior explained that medical staff are working to contain the spread throughout the squad and backroom team.
"Our club doctors are doing everything they can to contain what looks to be a virus because some members of our staff have come down with it as well," the head coach said.
The manager stressed the significance of returning to basics during his pre-match press conference ahead of the Brentford clash.
Liam Rosenior has won one and lost one of his first two games as Chelsea manager
| PA"We had a meeting today with the players about washing your hands, the basics, which is really important and hopefully we can contain it," Rosenior added.
"We have a busy period, so we need everyone ready, to be fit and healthy."
There was more encouraging news regarding Reece James and Cole Palmer, who both sat out the 3-2 defeat to Arsenal with minor hip and thigh problems respectively.
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Five facts about the Premier League | PA/GETTY/REUTERS/GBNEWSThe duo returned to training on Thursday and could feature against Brentford this weekend if they pass the necessary fitness assessments.
"Both of them are training today," Rosenior said at his pre-Brentford briefing.
"We need to assess them after training, to make sure they come through all of the protocols they need to come through."
The head coach expressed optimism about their availability for the Premier League encounter.
"It would be great to have them back in the squad. At the moment, it looks like they could be."
Rosenior also provided an update on Romeo Lavia, who has been absent for the past two months without clear explanation.
Chelsea striker Liam Delap won't be involved in his side's Premier League clash with Brentford on Saturday night | PAThe midfielder is now back on the training pitch working through his rehabilitation programme, though he has not yet rejoined the main group.
"Romeo is on the pitch. He's not with the group, but seeing him out on the pitch doing his rehab, he's looking really, really good," Rosenior said.
The head coach spoke warmly about the Belgian, describing him as "an outstanding footballer" whom he is eager to work with long-term.
No return date has been set for Lavia.
Separately, Chelsea are preparing to end Facundo Buonanotte's loan from Brighton, with the 21-year-old set to join Leeds instead for the remainder of the campaign.