Gillingham have been forced to close their stadium to the public because of Covid-19 cases.
The English Football League has implemented tighter training ground protocols.
The postponement of more of Saturday's scheduled games is due to positive cases at a number of clubs.
The minimum number of available players has also been updated.
There are a number of new postponements, one of which is the lunchtime Championship fixture between Cardiff City and Derby County.
Three of Saturday's Championship games had already been postponed for the same reasons, with a number across League One and League Two now also off.
The match between Queens Park Rangers andSwansea City was the first to be called off.
There are no new dates for the postponed games.
A number of positive Covid-19 cases being recorded at their respective training facilities led to the decision to postpone the match.
The latest postponements come a week after five of the premier league's games were postponed because of the virus.
The match between Manchester United and Brighton has been canceled.
Two National League clubs have forfeited their FA Trophy ties because of an outbreak in their camps.
The Championship match between Queens Park Rangers and Sheffield United was postponed on Monday due to an outbreak of cases.
The home ground of League One Gillingham will be closing because of cases involving club staff who were sent home.
A number of cases in the playing squad led to the postponement of their fixture at home to Crewe.
Saturday's matches have been postponed.
The Championship.
The game is between Derby County and Cardiff City.
Millwall is playing Preston.
The game is between Queens andSwansea City.
Reading plays Luton Town.
League One.
Gillingham is against Crewe.
Lincoln City is playing Doncaster.
The game is between Wednesday and Stanley.
League Two.
The game is between Crawley Town and Oldham Athletic.
Barrow v Northampton Town.
The Town of Swindon is playing the Town of Walsall.
