The blue-and-yellow defenders Emma Kullberg and Hanna Glas have previously been infected with covid-19.
Jonna Andersson, who showed symptoms of illness, trained on Thursday at the same time as the duo.
Later that day, the national team captain Peter Gerhardsson was asked about the players' medical condition and whether they tested positive or negative for the virus in new samples.
- I will not answer that.
I don't want to give Belgium a single advantage.
I have found out about things from the Belgian media that may be important, he said then.
The Belgian national team captain Ives Serneels responds to Sweden's choice to obscure the players' condition.
- For me it makes no sense, he can say what he wants.
I know what we are going to do tomorrow, and that is the most important thing, he says.
"Sees no problem"
The reason for Gerhardsson's choice to go dark is not to give Belgium any advantage.
- I'm not afraid of the information reaching the other side, it's football and the quarter-finals of the EC.
It shows some nervousness from the other side.
But for me I don't see a problem, replies Serneels.
- It doesn't change much.
We are playing against a good team with good players.
Regardless, they will start with a strong team on the court.
"Nothing I take time for now"
However, Serneels himself has not spoken to Gerhardsson.
- He seems to be a good coach considering what he did last year.
We'll see tomorrow if he's nervous or not.
It's not something I take time for now.
- They did well in the group stage.
If you look at the individual players and where they play and what they did last year, it's a strong team.
Each player has high individual quality.