Xu Wenbo, a scientist at the Chinese Center for Disease Control and Prevention, said on Sunday that scientists had successfully isolated the first strain of the virus, Efe news agency quoted the official newspaper People's Daily as saying.

The news comes after Chinese President Xi Jinping, following a meeting on Saturday, warned that the spread of the deadly illness was accelerating amid a fast-rising death toll.

Shanghai, one of the biggest cities in China, reported its first death due to the pandemic that has triggered panic across the country with authorities scrambling to stop its further outbreak.

The National Health Commission said the disease has infected a total of 1,975 people so far. In its latest report, the Commission said 15 deaths and 688 new cases were reported on Saturday.

Some 324 patients were said to be serious, while 49 have been discharged from hospitals after recovery.

Hubei, the province where the disease was first reported in its capital Wuhan, reported 52 deaths. One person each has died in Hebei (around Beijing), Heilongjiang (northeast), Henan (centre-east) and Shanghai (east).

Health authorities have carried out checkups on nearly 23,500 people who have come into close contact with infected persons. Out of these, over 21,500 continue to be monitored for symptoms.

At least 25 of China's 34 provincial divisions have been put on the highest-level health alert.

The southeastern city of Shantou has been partially closed down and interstate bus services in the cities of Beijing, Tianjin, Xian, and the Shandong province suspended.

Passengers at Beijing's 55 metro stations, including those linked to railway stations and the international airport, will be subjected to temperature screening to detect potential suspect cases.

Those with abnormal body temperatures would be hospitalized, according to state-run news agency Xinhua.

Cleaning and disinfection efforts have begun in metro and bus terminals in Beijing, where at least 51 cases of the so-called "Wuhan pneumonia" have been reported, official daily Global Times said.

Hubei province and other major cities were locked down earlier.

Shanghai has also announced the suspension of the train service that connects the city center with the Anting suburb, bordering Jiangsu province.

The prevention efforts include a large-scale purchase of face masks, as the respiratory system is believed to be the primary method of the virus' transmission.

Global Times said that 3.16 million face masks were shipped on Sunday to Wuhan.

Authorities have urged people who have recently visited Wuhan to stay inside their houses for 14 days and immediately contact health centres if they develop symptoms associated with the virus.

The disease has already spread to a dozen other countries with Canada confirming its first case on Saturday after a patient in Ontario tested positive. The man was said to have travelled from China recently.

Besides Canada, the cases reported outside China were six in Hong Kong; five each in Thailand and Macao; four in Australia; three each in South Korea, Taiwan, Singapore, Malaysia, Nepal and France; two each in Japan, the US and Vietnam.

Four Chinese nationals have been hospitalised in Pakistan for showing symptoms of the disease, but the country's health authorities have clarified that there were no confirmed cases of coronavirus as yet.

The World Health Organization has decided not to declare an international health emergency due to strict measures carried out in China that include complete suspension of transport and cancelation of Chinese New Year celebrations.

The symptoms of the new coronavirus, provisionally designated by the WHO as 2019-nCoV, are similar to those of cold but may be accompanied by fever and fatigue, dry cough and dyspnea (shortness of breath).