BEIJING (REUTERS) - The coronavirus transmission ability is getting stronger and infections could continue to rise, China's National Health Commission said on Sunday (Jan 26), with more than 2,000 people globally infected and 56 in China killed by the disease.

National Health Commission Minister Ma Xiaowei, speaking at a press briefing, said authorities' knowledge of the new virus was limited and they are unclear on the risks posed by mutations of the virus.

Ma said the incubation period for the coronavirus can range from one to 14 days, and that the virus is infectious during incubation, which was not the case with Severe Acute Respiratory Syndrome (Sars), a coronavirus that originated in China and killed nearly 800 people globally in 2002 and 2003.

Containment efforts, which have thus far included transportation and travel curbs and the cancellation of big events, will be intensified, Ma told a crowded news briefing on the second day of the Chinese New Year holiday.

The virus, believed to have originated late last year in a seafood market in the central Chinese city of Wuhan that was illegally selling wildlife, has spread to Chinese cities including Beijing and Shanghai, as well as the United States, Thailand, South Korea, Japan, Australia, France and Canada.

On Sunday, China announced a nationwide ban on the sale of wildlife in markets, restaurants, and e-commerce platforms.

President Xi Jinping said during a politburo meeting on Saturday that China was facing a "grave situation", as health authorities around the world scrambled to prevent a pandemic.