Yum! Brands Inc posted an estimated 5 percent same-store sales drop in China for October as the company struggles to recover from the consequences of avian flu and food safety concerns.

Yum! saw the same-store operational income of its subsidiary KFC Co Ltd drop by 7 percent but Pizza Hut Casual Dining went up 10 percent in October.

Executives had expected China restaurant sales to rebound in the current fourth quarter. However, they extended that recovery time after China's restaurant sales tumbled 11 percent in September.

David Novak, chief executive of the company, was quoted by Reuters as saying in October that Yum! must still fully convince diners in China that food at its KFC restaurants is safe as China launched investigations into possible violations among chicken suppliers.