The number of cases of a new coronavirus rose sharply on Wednesday (January 29).

In mainland China it's now already infected more people there than the SARS epidemic did in 2003.

That outbreak went on to kill nearly 800 people worldwide.

The new, previously unknown virus is sparking international alarm.

It's spreading fast with more than a dozen countries affected.

Scientists around the world are trying to get ahead of the virus.

And Australia on Wednesday announced a breakthrough.

A team of scientists said they've developed a lab-grown version of the virus, which could help combat its global spread.

Director of the lab Mike Catton:

(SOUNDBITE) (English) DIRECTOR OF VICTORIAN INFECTIOUS DISEASES LABORATORY, DR MIKE CATTON, SAYING:

"...we've moved immediately to share this with our international colleagues to provide a toolkit that compliments the modern molecular techniques that are so useful in diagnosis and development of vaccines and medicines."

Governments and businesses are working to contain the fallout.

In the U.S. the White House is holding daily meetings on the outbreak.

And some countries like Japan have sent chartered aircraft to Wuhan to evacuate their citizens.

Hong Kong - which has been gripped by anti-China unrest for months - is planning to suspend rail and ferry links with the mainland.

Airlines including United have announced they're canceling some flights to China, as demand for travel there falls sharply.

Other big companies like Starbucks are warning of a financial hit.

It's currently shut around half of its stores in China.

The country is a big market for Starbucks, accounting for 10 percent of its global revenue.

McDonalds and retailers like H&M have also closed some stores.

Other places though are seeing a surge in business.

Face masks have been flying off the shelves in dozens of cities.

A Beijing drug store is being fined over 400 thousand US dollars for hiking up the price of masks amid the outbreak.

As the death toll continues to rise, there's still important unknowns.

Like just how lethal it is, and whether it's infectious before symptoms even appear.