China is dealing with the outbreak of a mysterious virus that has infected around 300 people and killed six, as well as travelling to other countries.

Authorities are fighting to stop it from spreading as millions travel for Chinese New Year, and scientists are trying to understand the virus, which has not been seen by humans before, and its effects.

The virus, called 2019-nCoV, is a coronavirus which is one that infects the nose, throat, or sinuses and has pneumonia-like symptoms. Experts say it can be spread from human to human.

Here's what we know:

A mysterious virus was first reported Chinese city of Wuhan in December 2019.

BusinessInsider USA Images

Google Maps/Business Insider

The central Chinese city has a population of 11 million people.

Chinese authorities launched an investigation in the first week of January, amid fears that the virus could be like to SARS a virus that swept China and killed more than 700 people on the planet between 2002 and 2003.

BusinessInsider USA Images

AHMAD YUSNI / AFP) (Photo by AHMAD YUSNI/AFP via Getty Images

Source: BBC

But authorities later ruled that the virus is not SARS, even as more cases emerged. They said the virus had not been transmitted between humans.

BusinessInsider USA Images

AFP via Getty Images

It brings pneumonia-like symptoms including fever and difficulty breathing.

BusinessInsider USA Images

Tomohiro Ohsumi/Getty Images

Health officials believe the virus originated in a seafood market in Wuhan, and they initially said that they believed the virus could only spread from animals to humans.

BusinessInsider USA Images

Photo by Noel Celis/AFP via Getty Images

But China confirmed on January 20 that the deadly virus can be transferred from person to person, and not just from animals to humans.

"Now we can say it is certain that it is a human-to-human transmission phenomenon," Zhong Nanshan, the scientist the Chinese government appointed to lead the effort to battle the disease, said .

It was later identified as a coronavirus which infects the nose, throat, and sinuses referred to as the Wuhan virus, or 2019-nCoV.

BusinessInsider USA Images

STR/AFP via Getty Images

Much remains unknown about it, as it is a strain that has not been seen by humans before.

Many corona viruses are not considered very serious, and can only really prove dangerous to people with weakened immune systems.

But some are considered deadly like SARS.

As of January 21, the virus had killed six people,

BusinessInsider USA Images

Noel Celis/AFP via Getty Images

Source: Business Insider

China confirmed that around 300 people had been infected in the country as of January 21.

BusinessInsider USA Images

Associated Press

It said this included cases where the virus had spread to other parts of China, including Beijing, Guangdong province, Zhejiang province, Tianjin, and Shanghai.

BusinessInsider USA Images

NICOLAS ASFOURI/AFP via Getty Images

Cases are also suspected in more regions of China.

Source: Reuters

State media reported that transport hubs in Wuhan have been set up with infrared thermometers to try and catch people that might have been infected but this only started on January 14, potentially missing many people.

BusinessInsider USA Images

Reuters

Source: CNN .

The number infected could be higher than what authorities have identified.

BusinessInsider USA Images

Reuters

When China said that just 45 people had been infected, academics from Imperial College London suggested the true number of infected people was somewhere around 1,723.

If that ratio were still accurate on January 21, the true number of those infected would be more than 10,000.

And one case has been recorded in South Korea, one in Japan, one in Taiwan, and two in Thailand all from people from Wuhan or who had recently visited.

BusinessInsider USA Images

Associated Press

Other places, like Singapore, have reported suspected cases.

This map shows where cases have been confirmed, as of the morning of January 21.

BusinessInsider USA Images

Google Maps/Business Insider

The US Centers for Disease Control and Prevention are screening passengers arriving at three US airports from Wuhan.

BusinessInsider USA Images

David McNew/Getty Images

The airports are San Francisco International Airport, Los Angeles International Airport (LAX), and New York's JFK International Airport.

Authorities in Hong Kong, Singapore, and Tokyo are taking similar measures.

It comes as the virus' spread could get much worse as hundreds of millions prepare to travel for the huge, weeks-long Chinese New Year holiday a time referred to as the "largest annual human migration in the world."

BusinessInsider USA Images

Aly Song/Reuters

People will travel mostly bytrains, planes, roads, and ferries, both domestically and internationally. The first day of the new year is on Saturday.

China's National Health Commission said on Sunday that it will "step up our guard" and bring in new "control measures" in advance of the huge celebration.

BusinessInsider USA Images

Tomohiro Ohsumi/Getty Images

China's National Health Commission said on Sunday : "Our commission will step up our guard during the Spring Festival, pay close attention to the development and change of the epidemic, and direct the implementation of prevention and control measures."

The commission said on Sunday that it believes the virus is "still preventable and controllable."

BusinessInsider USA Images

STR/AFP via Getty Images

Source: Business Insider

The World Health Organization is figuring out how it should respond.

BusinessInsider USA Images

FABRICE COFFRINI/AFP via Getty Images

It said it will hold a meeting on Wednesday to decide whether to declare "a public health emergency of international concern," and what recommendations to make. It has previously declared such an emergency for swine flu and Ebola.

But for now, it is not recommending any sort of lockdown or end of movement: "Based on currently available information, WHO does not recommend any restriction of travel or trade."

BusinessInsider USA Images

Reuters

Chinese President Xi Jinping said on January 20 that keeping people alive needed to be the "top priority" and the virus' spread "should be resolutely contained."

BusinessInsider USA Images

Sergei Chirikov/AP Images

Source: NDTV .

See Also: