Medical staff transfer a patient at the Jinyintan hospital, where the patients with pneumonia caused by the new strain of coronavirus are being treated, in Wuhan, Hubei province, China, Jan.20, 2020.
Travelers pass through a health screening checkpoint at Wuhan Tianhe International Airport in Wuhan in southern China's Hubei province, Jan. 21, 2020.

The death toll in China from the outbreak of a new coronavirus has risen to six people, adding to fears of a global epidemic as reports of new cases spring up across China and beyond its borders.  

China's National Health Commission announced Monday that the virus, which causes a type of pneumonia, can be transmitted person-to-person and not just from animals to people.

All six fatalities have been reported in the central Chinese city of Wuhan, the epicenter of the outbreak, while health officials say the total number of cases has risen to 291, including 15 medical workers. The majority of cases are in Wuhan, but there have been new cases have confirmed in Beijing, Shanghai and Guangdong.  

South Korean health officials said Monday they confirmed a case in a 35-year-old woman who flew from Wuhan to Incheon, South Korea. Thailand and Japan have also confirmed cases.  

Passengers wearing masks are seen on a train at Shanghai railway station in Shanghai, China, Jan. 21, 2020.

Sales of face masks across China have spiked along with news of the growing spread of the outbreak.  Officials in Wuhan have begun screening passengers traveling by plane and train with infrared thermometers.  Health screenings of passengers traveling from Wuhan have also begun at airports in the United States, Japan, Thailand, South Korea and Singapore.  

Chinese and U.S. health officials are particularly concerned because many of the 1.4 billion Chinese citizens are expected to travel for the Lunar New Year holiday that starts January 25, both inside China and beyond.

Chinese health experts say they know little about the new strain, dubbed 2019-nCoV. They suspect the outbreak started in a Wuhan seafood market, which also sold other animals such as poultry, bats, marmots and wild game meat.

Medical staff and security personnel stop patients' family members from being too close to the Jinyintan hospital in Wuhan, Hubei province, China, Jan. 20, 2020.

The World Health Organization has said an animal source seemed to be "the most likely primary source" with "some limited human-to-human transmission occurring between close contacts." The WHO is convening an emergency committee Wednesday to discuss the situation.

Health officials are urging caution but say there is no reason to panic. The WHO is not recommending against travel to China, and China's National Health Commission says the current outbreak is "preventable and controllable."

A coronavirus is one of a large family of viruses that can cause illnesses ranging from the common cold to the deadly Severe Acute Respiratory Syndrome. SARS, which also started in China, killed nearly 800 people globally during an outbreak nearly 20 years ago. 

Sasmito Madrim in Jakarta contributed to this report.