Hubei authorities confirmed an additional 14,840 cases of the virus in Hubei on Wednesday, which brings the total number of cases in the epicenter of the outbreak to 48,206.
The Beijing administration announced that the number of people killed in China due to the Corona virus outbreak has reached 1,113, as well as 2,015 new cases.
Dale Fisher, chair of the Global Outbreak Alert & Response Network that is coordinated by the World Health Organization, said that predicted "time course" may well be true if the virus is allowed to run free in Wuhan. "We are not defenceless", Tedros said, adding, "If we invest now. we have a realistic chance of stopping this outbreak".
Singapore has reported 47 cases and worry about the spread is growing.
The patient was in isolation at a San Diego hospital, UC San Diego Health confirmed.
Another 97 people died in China, raising the national toll to 1,113, while more than 44,600 people have now been infected by newly named COVID-19 virus.
WHO chief Tedros Adhanom Ghebreyesus said on Tuesday the world had to "wake up and consider this enemy virus as public enemy number one" and the first vaccine was 18 months away.
China reported on Wednesday its lowest number of new coronavirus cases in two weeks.
A salesperson in the store's home appliance section was the first diagnosed on January 31, Xinhua said, and a series of cases followed.
But doubts have been aired on social media about how reliable the figures are, after the government last week amended guidelines on the classification of cases. One-third of Tianjin's 104 confirmed cases are in Baodi district, where the store is situated, the Xinhua News Agency reported.
The biggest cluster of cases outside China is on a cruise ship quarantined off Japan´s coast.
"We try to stay hopeful", American passenger Angela Jones told Reuters in a video recording.
Asked why there were so many cases in Singapore, he said there were comparatively more tests being conducted on the island.
The National Health Commission said 2,015 new cases had been tallied on Tuesday, the second straight daily decline and down from almost 3,900 a week ago. The Singapore bank said all staff on the same floor should do so as a precautionary measure.
The WHO said identifying the animal source of the COVID-2019 would help "ensure that there will be no further future similar outbreaks with the same virus and will also help understand the initial spread of the disease in the Wuhan area". It is suspected to have come from a market that illegally traded wildlife in Hubei's capital of Wuhan in December.
Most of the cases have been in Hubei, where about 56 million people have been placed under virtual quarantine.
With companies laying off workers and supply chains from the auto industry to smartphones disrupted, China's economy is taking a big hit. Supply chains for makers of items from cars to smartphones have broken down. ANZ Bank said first-quarter growth may slow to between 3.2%-4.0%, down from a projection of 5.0%.