Have a good look at the fan hub for any streaks of oil weeping from there. Also give the fan a good turn by hand, it should spin then stop after a quarter of a turn, there is a possibility that the fan clutch has failed.
It's hard to see on my screen, have you checked all the hoses and the coolant level for loss?. When the fluid leaks from the fan it's not a huge amount but you can defiantly see evidence that it's come from the fan hub.