Timeline: How China's new coronavirus spread
Chinese authorities have closed off almost 20 cities amid efforts to contain a new coronavirus that has killed more than 50 people in recent weeks, with cases confirmed in several countries in Asia and beyond.
Below is a timeline.
On December 31, China alerts the World Health Organization (WHO) to several cases of pneumonia in Wuhan, a port city of 11 million people in the central Hubei province. The virus is unknown.
Several of the ill worked at the city’s Huanan Seafood Wholesale Market, which is shut down on January 1.
As health experts try to identify the virus amid growing alarm, the number of infections exceeds 40.
On January 5, Chinese officials rule out the severe acute respiratory syndrome (SARS) virus – an illness that originated in China and killed more than 770 people worldwide over 2002-2003.
On January 7, they announce they have identified a new virus, the WHO reports. It is from the coronavirus family, which includes SARS and the common cold, and is named 2019-nCoV. Coronaviruses are common and spread through coughing, sneezing, or touching an infected person.
China’s Hubei: ‘Epicentre’ of coronavirus (2:14)
China announces on January 11 its first death, that of a 61-year-old man who had purchased goods from the seafood market. Treatments did not improve his symptoms after he was admitted to hospital and he died on the evening of January 9 when his heart failed.
On January 13, WHO reports a case in Thailand, the first outside of China, of a woman who had arrived from Wuhan.
On January 16, Japan’s health ministry reports a confirmed case of a man who had also visited the city.
On January 17, as a second death is reported in Wuhan, health authorities in the United States announce the start of screening at three airports of passengers arriving from the city.
Authorities in the US, Nepal, France, Australia, Malaysia, Singapore, South Korea, Vietnam and Taiwan confirm cases over the following days.
On January 20, China reports a third death and more than 200 infections, with cases also reported outside Hubei province including in the capital, Beijing, Shanghai and Shenzhen.
Meanwhile, a Chinese expert on infectious diseases tells state broadcaster CCTV that human-to-human transmission is “affirmative”, raising fears of a major outbreak of as millions travel for the Lunar New Year holiday.
Asian countries ramp up measures to block the spread of the virus, introducing mandatory screenings at airports of arrivals from high-risk areas of China.
On January 22, the death toll in China jumps to 17 with more than 550 infections. Many European airports step up checks on flights from Wuhan.
The city is placed under effective quarantine on January 23 as air and rail departures are suspended.
The same measures are announced for two more cities in Hubei province, Xiantao and Chibi.
Beijing cancels events for the Lunar New Year starting on January 25, while officials report the first death outside of Hubei.
The WHO says later on January 23the outbreak does not yet constitute a public emergency of international concern and there is “no evidence” at the moment of the virus spreading between humans outside of China.
Coronavirus: Footage from inside hospital in Wuhan (1:29)
By January 24, the death toll in China stands at 26, with the government reporting more than 830 infections.
The number of cities under shutdown in Hubei rises to 13, affecting 41 million people.
Shanghai Disneyland shuts down and some cities announce the closure of entertainment venues. Beijing says a section of the Great Wall and other famous landmarks will also be closed.
On January 25, travel restrictions are imposed on a further five cities in Hubei province, taking the overall number of people affected to 56 million.
Hong Kong meanwhile declares a virus emergency, cancels Lunar New Year celebrations and restrictslinks to mainland China.
SOURCE: Al Jazeera and news agencies