Melbourne, March 12 (IANS): World champion Lewis Hamilton says he has been shocked with Formula 1 pressing ahead with this weekend's Australian Grand Prix amid the global coronavirus outbreak.

"I am very, very surprised we are here," BBC Sport quoted Hamilton as saying in the official news conference on Thursday. "It's great we have races but it's shocking we are sitting in this room," he added.

The season-opening race in Melbourne is set to go as per schedule despite mounting fears about the spread of the disease, which has now been declared a "pandemic" by the World Health Organisation.

Earlier, the NBA also suspended its season indefinitely after a Utah Jazz player tested positive for coronavirus. The United States has also banned flights from 26 European countries to the US.

"(There are) so many fans there and it seems like the rest of the world is reacting - probably a little bit late," Hamilton said. "But we are seeing Trump shutting down the borders, the NBA has been suspended yet F1 continues to go on," he added.

Meanwhile, Ferrari driver Sebastian Vettel said it was difficult to judge what to do as the virus continues to spread.

"It is very difficult having a fair judgment, but I do realise a lot of sporting competitions get cancelled and it is fair to ask the question why you are here.

"We have to trust (motorsport's governing body) FIA and for them to take all the precautions but the answer no one can give you is how much you can control what is going on," he added.

Around 150 confirmed cases of coronavirus have been reported so far in Australia, including a fan who attended the women's T20 Cricket World Cup final between Australia and India on March 8 at the Melbourne Cricket Ground.