The global coronavirus crisis could throw F1's 2020 season into chaos.
China has already been postponed, but now the other three races at the top of the calendar - Australia, Bahrain and Vietnam - are in doubt.
F1 CEO Chase Carey said in a teleconference that the sport is indeed "heading to Melbourne, heading to Bahrain and heading to Hanoi."
But even in Barcelona for winter testing, members of the Italian-based Ferrari and Alpha Tauri teams have had to stay at home.
"A number of engineers did not come here as a precaution," Ferrari's Mattia Binotto revealed.
"So it is definitely a concern for us. We are being cautious and ensuring we are acting properly."
A series of crisis meetings have been scheduled in Barcelona, with the biggest concern being how team staff are able to fly into countries with restrictions.
Vietnam is now admitting that its brand new Hanoi race could be in trouble.
"If the situation in March gets complicated, we may have to cancel it," Hanoi official Nguyen Duc Chung is quoted by DPA news agency.
"I cannot say with 100 percent certainty that it will take place."
Travel restrictions put in place for those travelling to Bahrain are also threatening that race, which is scheduled for March 22.
Some publications are even speculating that the season may not be able to begin until Zandvoort in May.
"It (coronavirus) can really have a major impact," said Red Bull's Dr Helmut Marko. "Also for Australia and Bahrain.
"Australia is already not allowing people to come in through Singapore or Hong Kong, and to Bahrain from Dubai. They are all important transfer points for many people," he told Austria's ORF broadcaster.
"The effects of the virus can be really extensive for our sport," Marko continued. "The logistical challenges in particular could become too big."
Alfa Romeo team manager Beat Zehnder said creative logistical solutions may not even be sufficient to solve the problem.
"First, you cannot simply rebook for hundreds of people," he told Auto Motor und Sport. "Second, nobody knows how the situation will develop.
"You could book Oman today, and Oman is closed tomorrow."
Haas boss Gunther Steiner said meetings to talk about the logistical problems are scheduled, but warns: "We cannot really prepare, we can only react."
Alfa Romeo tester Robert Kubica said he even decided to travel to Barcelona by car rather than plane because of the situation.
"I heard what is happening in Italy and elsewhere," he said. "I came here by car. If the airports are closed, I can still go home.
"The main thing is that everyone is healthy. It's important for drivers like us to drive, it's what we live for, but the most important thing is health."
