Northern Ireland international Little has scored two goals in 16 games for Preston since signing from Scottish side Rangers in June 2014.
The 26-year-old made five appearances on loan at Blackpool earlier this term.
Fosu, 20, has played once for Reading, but featured in six games for Fleetwood after joining on loan in November.
"Andy's suffered with injuries this year so this is a chance for him to get some football and get himself back on track," Stanley manager John Coleman told the club website.
"When you've not played for while you just want to play and I think the exposure to the first team he'll get will do him good."
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Promotion-chasing Accrington Stanley have signed Preston striker Andy Little and Reading winger Tarique Fosu on loan until the end of the season.