From www.Wikipedia.com

Casu marzu (also called casu modde, casu cundhídu, or in Italian formaggio marcio) is a cheese found in Sardina, Italy notable for being riddled with live insect larvae. Casu marzumeans “rotten cheese” in Sardinia and is known colloquially as maggot cheese.

Derived from Pecorino Sardo, casu marzu goes beyond typical fermentation to a stage most would consider decomposition brought about by the digestive action of the larvae of the cheese fly Piophila casei. These larvae are deliberately introduced to the cheese, promoting an advanced level of fermentation and breaking down of the cheese’s fats. The texture of the cheese becomes very soft, with some liquid (called lagrima, from the Sardinian for “tears” seeping out. The larvae themselves appear as translucent white worms, about 8 mm (1/3 inch) long. When disturbed, the larvae can jump for distances up to 15 cm (6 inches), prompting recommendations of eye protection for those eating the cheese. Some people clear the larvae from the cheese before consuming; others do not.

Yaroslav Trofimov, in the August 23, 2000 edition of The Wall Street Journal, describes the cheese as “a viscous, pungent goo that burns the tongue and can affect other parts of the body”. Susan Herrmann Loomis reports an encounter (in a 2002 Bon Appétit article)