Watford manager Nigel Pearson has revealed a further two squad players are now self-isolating after members of their family tested positive for Covid-19.
Adrian Mariappa, alongside two staff members, tested positive for the virus following the Premier League's first round of testing earlier this week.
Club captain Troy Deeney - alongside a number of squad members - are also staying away from training amid safety concerns.
"The testing situation is obviously to minimise risk, so for the players and staff who have been in this week statistically they should be a lot safer but it is still a surprise for those who have tested positive," boss Pearson told reporters.
"They're all feeling OK, and likewise for their families as well. That is important for us to make sure that those people - their health is OK.
"In addition to that we've had a couple more people who have to be in isolation because they've been in close contact with people who have tested positive, even though their own result came back negative.
"I think that shows the types of complications that we've got. Today everybody has been tested again, we were tested on Friday morning, and we await further results over the weekend now.
"It is just something we have got to get used to. We are trying, as everybody will be, to establish what is now a more normal working practice in the circumstances that we have. That is what we have got to work with. But they're OK."
Regarding the number of squad members absent from training this week, Pearson added: "One through testing positive, two more through being in contact with somebody else and the others because they decided not to come in.
"I don't intend to give specific numbers, but we've had several players who have not been available for different reasons this week, but it is what it is.
"We can't do much about that at the moment and hopefully that situation will change in time."
Additional reporting by PA.
