Each day, new cases of coronavirus are reported around the world, and as a result, travel advice is constantly being revised and updated by authorities.

Key points: Australians are advised not to travel to China, or if in China, to leave as soon as possible

Australians are advised not to travel to China, or if in China, to leave as soon as possible Exercise a high level of caution if travelling to Japan, South Korea, Hong Kong, Indonesia or Thailand

Exercise a high level of caution if travelling to Japan, South Korea, Hong Kong, Indonesia or Thailand There are high numbers of coronavirus cases in Italy and Singapore but only normal caution is advised

COVID-19 has been declared a public health emergency by the World Health Organisation (WHO) but what does this mean for your travel plans?

Places you can't go

Smart Traveller has advised people not to travel to mainland China due to the outbreak.

"If you are currently in China, leave as soon as possible by commercial means," Smart Traveller advises.

"Monitor your health closely and follow the advice of local authorities."

Travellers are also advised to expect further restrictions and travel disruptions as other countries take measures to control the spread of the virus.

Many countries won't allow entry to people who have been in mainland China in the past 14 days. This includes road travel via Mongolia.

Where to exercise high degree of caution

If you're travelling to Japan, South Korea, Hong Kong, Indonesia or Thailand, you should exercise a high degree of caution and monitor your health closely.

This is due to the heightened risk of "sustained local transmission" of the virus.

"The risk of COVID-19 in these countries is currently thought to be low compared to mainland China," Smart Traveller states.

In South Korea, people are advised to reconsider travelling to Daegu and Cheongdo.

Expect increased screenings in these countries.

In Thailand, you'll be quarantined if you have symptoms.

Indonesia is temporarily denying entry and transit to foreign nationals who have been in mainland China in the previous 14 days.

Indonesia will also stop all direct flights to and from mainland China.

No travel ban but high number of cases

Italy currently has the highest number of cases of coronavirus in mainland Europe but at this stage, there aren't any travel warnings in place.

Travellers are advised to exercise normal safety precautions.

Despite this, authorities cancelled the remainder of the Venice Carnival.

The last two days of the world-famous Venice Carnival have been cancelled. ( AP: Luigi Costantini )

Italian authorities also introduced measures to restrict the use of public spaces and limit travel in some parts of northern Italy.

While Singapore has a higher number of coronavirus cases than Hong Kong, there is no added advice beyond normal safety precautions.

Visit smarttraveller.gov.au for more information on current warnings and advice.