Watford defender Adrian Mariappa says he is one of three people who tested positive for coronavirus at the club.
On Tuesday, it was announced there had been six positive tests across three Premier League clubs.
Two staff at Watford and Burnley assistant manager Ian Woan also tested positive, while the two others at a third club have not yet been revealed.
Chelsea's N'Golo Kante missed training over coronavirus fears, with the backing of his manager Frank Lampard.
Kante's decision to train at home follows a similar stance by Watford captain Troy Deeney and several of his team-mates.
France midfielder Kante returned to Chelsea's first day of restricted phase one training on Tuesday after a negative coronavirus test, but was given compassionate leave on Wednesday, reported the Telegraph.
'I feel fit as ever' - Mariappa
"It was a big surprise because I haven't really left the house," Mariappa, 33, said, also speaking to the Telegraph
"Apart from some exercise and the odd walk with the kids, I've mainly just been homeschooling and keeping fit.
"My lifestyle is very quiet, certainly no parties or going out or anything, so I really don't know how I got it."
The Jamaica international said he has had no symptoms and felt "as fit as ever".
He added: "It's quite scary how you can feel absolutely fine and not really have left the house, and yet still get the virus.
"If it wasn't for the fact I had gone back to training and had this test, then I'd never have found out that I had the virus and I would just be getting on with things as normal. That's obviously quite a strange thought."
Players and staff who have tested positive will now self-isolate for seven days.
The six positive results came as squads started non-contact training on Tuesday, as the Premier League steps up plans for a restart.
A total of 748 players and staff from 19 clubs were tested. Norwich City did their tests on Tuesday and did not return any positives results.
Deeney and other Watford players stay away
Before the news about Watford's positive tests emerged, captain Troy Deeney said he would not return to training because he feared for his family's health.
A number of other team-mates have joined Deeney's stance in not training and they will follow individual programmes at home.
They want reassurances to questions they have around the return to training protocols and the specifics around the spread of the virus.
"We're due back in this week. I've said I'm not going in," Deeney, 31, told Eddie Hearn and Tony Bellew on the Talk the Talk YouTube show.
"It only takes one person to get infected within the group and I don't want to be bringing that home.
"My son is only five months old. He had breathing difficulties, so I don't want to come home to put him in more danger."
In an interview with the Sunday Times, manager Nigel Pearson expressed his own concerns about the situation and said he would not insist on players reporting for training.
Speaking to the Manchester United club website, captain Harry Maguire said: "It's been a strange few months, but it has been a protocol which the club has followed.
"It seems such a safe environment. It's our first day back today, but it seems so safe and everyone is respecting it so well, so long may that continue and I'm sure no one will have any problems."
The Premier League has been suspended since 13 March because of the Covid-19 pandemic, with 92 fixtures remaining.
The league had previously identified 12 June for matches to possibly start again, but there is now an expectation this will need to be pushed back.