Marcus Grate will not start in Thursday's World Cup sprint in Drammen, Norway.
"Unfortunately, they are not a 'dance on roses' this season, I have also tested positive for Covid-19 after Lahti," writes Marcus Grate.
The Umeå skier took part in Lahti last weekend and ran the sprint where it stopped in the quarter finals.
SVT Sport is looking for national team doctor Jan Wall.