The effort is based on the girl's photo and DNA profile, which have been communicated to all Interpol member countries, the organisation based in the French city of Lyon said yesterday.
The information was contained in a so-called yellow notice which is circulated by Interpol to help locate missing persons, especially minors, or, as in this case, identify people who cannot identify themselves, it said.
"Until now, a comparison of the girl's profile against Interpol's global DNA database has not produced a match," the organisation said in a statement.
It recalled that the Greek authorities were investigating whether the girl may have been abducted or been a victim of child traffickers.
The girl, known as Maria, was found by police last week in a Roma camp near the town of Farsala in central Greece.
Initially thought to be four years old, but later confirmed from dental checks to be five or six, she was kept by a Roma couple who were placed in pre-trial detention on Monday for allegedly abducting her.
"At the request of the Greek authorities, Interpol has also issued blue notices for Christos Salis and Eleftheria Dimopoulou, the couple in whose home the girl was found," the organisation said.
"Blue notices are issued to collect additional information about a person's identity, location or activities," it said.
