China’s deadly coronavirus outbreak is dominating headlines worldwide, raising fears of a global epidemic.
Since the first sufferer was infected in the city of Wuhan - capital of Hubei province - at the end of last year, the virus has spread to major cities like Beijing and Shanghai.
READ MORE: How did China's coronavirus outbreak start?
It has even crossed national borders, with the US, Japan, South Korea, Thailand and Taiwan all confirming cases.
The death toll stood at 18 on Thursday, all in Wuhan, with Chinese authorities confirming more than 630 people are battling the virus.
One expert claims, however, numbers are rising “by the minute” - with up to 9,700 cases in Wuhan alone.
How deadly is the new coronavirus?
With the strain - 2019-nCoV - virtually unheard of a month ago, estimations are based on limited data.
Statistics point to a death rate of 2%, meaning that for every 50 people who catch the virus, one will die, Yahoo UK reported.
Of the cases that end up in hospital, between 15% and 20% are said to be “severe”, defined as needing ventilation.
Fatalities are occurring as a result of pneumonia, which comes about when a respiratory infection causes the alveoli (air sacs) in the lungs to become inflamed and filled with fluid or pus, according to the American Lung Association.
The lungs then struggle to draw in air, resulting in reduced oxygen in the bloodstream.
“Without treatment the end is inevitable,” said the charity Médecins Sans Frontières.
“Deaths occurs because of asphyxiation.”
Genetic analyses reveal 2019-nCoV is more closely related to fellow coronavirus severe acute respiratory syndrome (Sars) than any other strain.
Sars made headlines in the early 2000s after 774 people died across dozens of countries.
Professor Neil Ferguson, from Imperial College London, claims Sars was “nearly universally severe”.
Whereas 2019-nCoV cases are being described as “mild” for the most part.
Chinese officials were notoriously “tight lipped” about the Sars epidemic.
“The authorities have been much more open about the outbreak, investigated the infection much more rapidly and thoroughly, and shared that information with the international community,” Professor Paul Hunter, from the University of East Anglia, said.
“The authorities have also initiated very strong control measures in affected cities.
“The causative virus was also identified substantially earlier in this epidemic.
“As a result of this increased openness and better management in neighbouring countries should be able to prepare well in advance of any cases that may arrive on their shores.”
Coronaviruses are a class of pathogens that cause everything from the common cold to life-threatening epidemics like Middle East respiratory syndrome (Mers).
Six previous coronaviruses are known to infect people, with 2019-nCoV being the “seventh”.
The new coronavirus strain likely originated at a seafood market in Wuhan.
The market also sold a range of processed and live meat including donkeys, poultry, camels, foxes, badgers, hedgehogs and rats.
Most of those who initially fell ill worked at, or visited, the market.
Viruses like 2019-nCoV “mutate all the time”, allowing them to “jump” between species.
Scientists from Peking University in Beijing believe 2019-nCoV likely started in bats.
These then got eaten by snakes, which acted as an “intermediate host”, before the virus spread to humans.
Professor Hunter argued, however, it is “not known with certainty and may never be definitively proved”.
Like other coronavirus strains, 2019-nCoV typically starts with flu-like symptoms, including fever, cough, shortness of breath and breathing difficulties.
Symptoms can come on in as little as two days or as long as two weeks after exposure, according to the Centers for Disease Control and Prevention (CDC).
In severe cases, patients develop pneumonia.
Who is most likely to be affected by the new coronavirus?
The new strain has the potential to infect anyone.
“Novel viruses spread much faster because we have no immunity,” Professor Ferguson said.
China's National Health Commission announced the youngest victim to date was 48 and the eldest 89.
Most were elderly and suffering other health issues, like Parkinson’s or diabetes, it added.
Other strains of coronavirus tend to only trigger serious complications - like pneumonia or bronchitis - in the elderly, young or those with pre-existing medical conditions.
How does the new coronavirus spread?
China's National Health Commission confirmed the virus can spread from person-to-person.
Coronaviruses are usually transmitted via coughing, sneezing, shaking hands or touching a contaminated object.
The virus enters the body if contaminated hands touch the eyes, nose or mouth.
In rare cases, faecal contamination can be to blame.
Exposure to the mysterious animal behind the outbreak could also lead to infection.
The CDC stresses some viruses are highly contagious and others less so. It is unclear where 2019-nCoV stands.
How is the new coronavirus treated?
There is no specific treatment for coronaviruses, according to the CDC.
If the infection triggers pneumonia, doctors work to combat the complication.
When a virus is to blame – like 2019-nCoV – pneumonia may be treated via “antiviral medication”, according to the American Lung Association.
Professor Peter Horby - from the University of Oxford - said, however, there is likely “no effective anti-viral”, with care being “supportive”.
US health officials are working on a vaccine against 2019-nCoV; however, it will likely be months before the first stage of trials are underway and more than a year before it could be available to the public, CNN reported.
For now, the World Health Organization advises people eat only well-cooked food, “avoid spitting in public” and stay away from sick animals.
The CDC recommends washing hands with soap and water for at least 20 seconds or using an alcohol-based sanitiser.
People should also stay home if they feel unwell, disinfect objects and cough or sneeze into a tissue, which they then throw away.