ROME (AFP) - Rome had an empty feeling on Wednesday with some 20 percent of its somewhat superstitious residents failing to show up for work or going to school because of a prophecy predicting a devastating earthquake.

"Twenty percent of Romans didn't go to work today. On the other hand hotels and agritourism facilities have had a boom in bookings," said Primo Mastrantoni, head of the Association for the Rights of Users and Consumers.

Traffic was particularly light on the Italian capital's normally clogged streets and the usual crowds in the metro and outside schools were absent.

Shopkeepers in the Chinese-dominated Esquilino quarter took off, with nine out of 10 shops shuttered with signs saying "illness" or "re-stocking."

"Some of Rome's residents believed the rumor in the same way they believe magicians, sorcerers and astrologers," Mastrantoni said, referring to the supposed prophecy from a self-taught Italian seismologist who died in 1979.

An institute set up to study the writings of Raffaele Bendandi has emphasized that he never made a prediction of an earthquake in Rome on May 11 but that has done little to stop the rumor spreading by word of mouth.

The civil protection agency and Rome city hall have both stressed there will not be an earthquake and Italy's main earthquake institute has gone out of its way to tell people that the Eternal City has never suffered a major tremor.

That didn't stop 400 people from joining a Facebook group whose members spent the night camped out in the wide open spaces of the Circus Maximus, an ancient Roman arena.

Others organized giant earthquake picnics in the city's many parks.