Cognomen 西贾 (Siggia 
, 西贾) , in the entire world, is a rare surname. The cognomen 西贾 is habitual in Italy, where it is a rare surname, Canada, where it is a very rare surname, and Belgium. In absolute terms, it is the most numerous in Italy, the United States, and Brazil. Very seldom, 西贾 is the forename as well as the last name.