The second round on the MotoGP calendar is scheduled for Thailand on March 22, but that too has been the subject of some uncertainty.
Next weekend's season-opening MotoGP race in Qatar has been cancelled because of travel restrictions on passengers from Italy and elsewhere due to the coronavirus epidemic, MotoGP said on Sunday.
The floodlit night race was scheduled for the Losail circuit on March 8.
The joint statement by MotoGP, the governing FIM and teams' association IRTA said that as of Sunday all passengers arriving in Doha on direct flights from Italy, or who had been in Italy in the past two weeks, faced a minimum of 14 days in quarantine.
"Italy clearly plays a vital role in the championship and in the MotoGP class -- both on track and off -- and therefore the decision has been taken to cancel premier class competition," it said.
The Moto2 and Moto3 categories will still race due to those teams and riders already being in Qatar for three days of testing last week.
Ducati and Aprilia are Italy-based teams while Italian riders include Yamaha's MotoGP great Valentino Rossi. The 22-strong grid features six Italian riders, with engineers and mechanics across the paddock.
The death toll from an outbreak of coronavirus in Italy has risen to 34, the Civil Protection Agency said on Sunday, with the cumulative number of confirmed cases totalling some 1,694 in the worst such contagion in Europe.
The second round on the MotoGP calendar is scheduled for Thailand on March 22, but that too has been the subject of some uncertainty.
Formula One, whose season starts in Australia on March 15, has already cancelled the Chinese Grand Prix scheduled for Shanghai on April 19.
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