The World Health Organization (WHO) has declared the new coronavirus outbreak, which originated in Wuhan, China, a global health emergency.
At least 2,236 people have died in mainland China and more than 76,000 people have been infected worldwide, mostly in China.
Deaths have been confirmed in Hong Kong, the Philippines, Japan, France, Iran, Taiwan and South Korea.
Here is what you need to know:
What is a coronavirus?
The coronaviruses family cause illnesses ranging from the common cold to more severe diseases such as severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), according to the WHO.
They circulate in animals and some can be transmitted between animals and humans. Several coronaviruses are circulating in animals that have not yet infected humans.
The new coronavirus, the seventh known to affect humans, has been named COVID-19.
What are the symptoms?
Common signs of infection include fever, coughing and breathing difficulties. In severe cases, it can cause pneumonia, multiple organ failure and death.
The incubation period of COVID-19 is thought to be between one and 14 days. It is contagious before symptoms appear.
Infected patients can be also asymptomatic, meaning they do not display any symptoms despite having the virus in their systems.
How many people are affected?
In mainland China, at least 2,236 people died and at least 75,400 have been infected, according to official figures.
Deaths have also been confirmed in Hong Kong, the Philippines, Japan, France, Taiwan, Iran and South Korea.
Cases have been confirmed in Australia, Belgium, Cambodia, Canada, Egypt, Finland, France, Germany, Hong Kong, India, Italy, Iran, Israel, Japan, Macau, Malaysia, Nepal, the Philippines, Russia, Singapore, Spain, Sri Lanka, Sweden, Taiwan, Thailand, the UAE, the UK, the US and Vietnam.
Where did it come from?
China alerted the WHO to cases of unusual pneumonia in Wuhan on December 31.
COVID-19 is thought to have originated in a seafood market where wildlife was sold illegally.
On February 7, Chinese researchers said the virus could have spread from an infected animal to humans through illegally trafficked pangolins, prized in Asia for food and medicine.
Scientists have pointed to either bats or snakes as the possible source.
What is happening in China now?
Efforts to contain the outbreak have caused disruption in China, with some 20 cities facing travel restrictions affecting at least 60 million people.
More than a dozen countries have evacuated their citizens from Wuhan, while others have banned entry to Chinese citizens. Several airlines have suspended flights to and from China.
On February 10, a team of WHO experts arrived in China to investigate the outbreak.
Should I worry? How can I protect myself?
The WHO declared the virus a global health emergency on January 30, deeming it an “extraordinary event” that constitutes a risk to other countries and requires a coordinated international response.
People are being urged to follow local safety measures.
WHO recommends basic hygiene such as washing hands with soap and water and covering your mouth with your elbow when sneezing or coughing.
Maintain “social distancing” – keeping at least one metre (three feet) between yourself and others – particularly if they are coughing and sneezing, and avoid touching your face, eyes and mouth with unwashed hands.
Avoid unnecessary, unprotected contact with animals and be sure to thoroughly wash hands after contact.
Ensure meat consumed is cooked thoroughly.
Where have cases been reported?
Most cases and deaths have been reported in China – the vast majority in Hubei province.
Deaths have also been confirmed in Hong Kong, the Philippines, Japan, France, Taiwan, South Korea, Italy and Iran.
The virus has spread to many countries in the Asia-Pacific region as well as in Europe, North America, the Middle East and Africa. The majority of cases outside China are among people who recently travelled to the country, however instances of human-to-human transmission have been recorded in several countries and questions have been raised about cases with no apparent link to China.
What is being done to stop it from spreading?
Scientists around the globe are racing to develop a vaccine but have warned that one is unlikely to be available for mass distribution before 2021.
Meanwhile, Chinese authorities have effectively sealed off Wuhan and placed restrictions on travel to and from several other cities, affecting some 60 million people.
Many international airlines have cancelled flights to China. Some countries have banned Chinese nationals from entering their territories and several more have evacuated their citizens from Wuhan.
Where did the virus originate?
Chinese health authorities are still trying to determine the origin of the virus, which they say likely came from a seafood market in Wuhan where wildlife was also traded illegally.
On February 7, Chinese researchers said the virus could have spread from an infected animal species to humans through illegally-trafficked pangolins, which are prized in Asia for food and medicine.
Scientists have pointed to either bats or snakes as the source of the virus.
Is this a global emergency?
The outbreak now constitutes a global health emergency, the WHO said on January 30.
The decision to sound the top-level alarm was made after the first cases of human-to-human transmission outside China were confirmed.
The international health alert is a call to countries around the world to coordinate their response under the guidance of the United Nations health agency.