Shanghai | The Chinese government is under pressure to contain rising panic about the outbreak of a mysterious virus spreading throughout the country, as the death toll rose to nine and the number of reported infections doubled to more than 400 in just 24 hours.
Face masks and disinfectant were selling out in many parts of China, as people suspected of being infected with the disease in the central Chinese city of Wuhan - where the virus originated - were quarantined.
Still, hundreds of millions of people continued to pack train stations and airports to travel home for the Lunar New Year holiday. Health authorities said they were checking passengers at airports and train and bus stations for symptoms of the respiratory virus, which has raised fears of a repeat of the 2009 SARS crisis.
The United States also reported its first case of the coronavirus, which can be spread from human to human. An Australian man has been tested for the virus after returning to Brisbane from Wuhan.
Li Bing, vice-director of China's National Health Commission, said in a press conference on Wednesday there was a possibility the virus would mutate.
He and other health officials warned the source of the virus still had not been identified, and the way it is transmitted was not fully understood. It has been classified as a B Infectious Disease.
He also warned there was a risk the spread of the virus could accelerate. There are another 1394 suspected cases with patients under medical observation. There has been one confirmed case in Japan, three in Thailand, one in South Korea and one in Taiwan.
Officials at China's airports are checking passengers for fevers as the country seeks to control the outbreak of a new virus. There are 278 confirmed cases of the disease, which threatens to spread further during the Lunar New Year travel rush.
"We don't fully understand the virus. We are still in the process of understanding it and trying our upmost to contain it," Mr Li said when asked if the virus was highly contagious.
Reports of infected people now cover 13 provinces in China, confirming fears that the virus was spreading rapidly throughout the vast country as many citizens travelled home to see relatives for the holidays.
In Shanghai, where there have been nine reported cases, many pedestrians were wearing face masks as they finished up work for the holidays or went shopping for Lunar New Year gifts. Some parents kept their children out of school.
Health officials said the number of cases had increased dramatically because they were getting better at diagnosing the symptoms.
Most of the cases were reported in central China near Wuhan, a city of 11 million people where the virus was believed to have originated in a meat and seafood market. There were also reported cases in Beijing, Shanghai and other provinces throughout China.
Employees at large government-owned companies told The Australian Financial Review they were asked to inform their employers if they had travelled to Wuhan in the past month.
Authorities were also urging people not to leave the city. Airlines, train operators and travel companies were offering travellers full refunds on tickets to and from Wuhan.
One woman working for a pharmaceutical company said sales of surgical masks were being rationed as supplies ran out. Supplies of masks and disinfectant liquids were also selling out on online shopping platforms, where many people in China to their shopping.
The outbreak is the latest challenge for China's leaders, who attempted to present Beijing's handling of the outbreak as more open and transparent than the government cover-up of the SARS crisis. President Xi Jinping said earlier in the week that all measures must be taken to contain the virus.
However, there was rising criticism on social media on the way the Chinese government had handled the outbreak. Local authorites in Wuhan were accused of being slow to acknowledge the seriousness of the virus and were accused of initially trying to cover it up.
Local media said eight people were questioned by police in Wuhan earlier in the year for "spreading false information" after they warned on social media that the virus could be a repeat of SARS.
Many in China are sceptical of Beijing's assessment of the outbreak, given the government's track record downplaying SARS. The Hong Kong media were the first to report the extent of the spread of the virus, which had previously believed to be contained to Wuhan.