Australian firefighters have managed to control a bushfire that burned more than half of the Unesco world heritage-listed Fraser Island, around two months after a suspected illegal campfire sparked the blaze.

The fire on the world's largest sand island, off Australia's east coast, destroyed large swathes of the isle's forests before heavy downpours arrived over the weekend.

"With the help of welcome rainfall and a massive response from crews, the fire is now contained," Queensland Fire and Emergency Services tweeted on Sunday.