Luis Enrique’s side fear more players could test positive and, as a result, they have players on standby training separately.
Kepa will land in Madrid on Tuesday afternoon and join training on Wednesday as Spain prepare to kick of their Euro 2020 campaign against Sweden in Group E on Monday.
Spain had been due to play Lithuania in a friendly on Tuesday, but they had to pull out after Busquets’ positive test.
The country’s Under-21 side will play the game instead.
So far all of Spain’s other players and staff members have tested negative for Covid, with sports minister Jose Manuel Rodriguez Uribes confirming that the squad will receive vaccines on Wednesday.