In late December, Chinese public health officials informed the World Health Organization that they had a problem: an unknown, new virus causing pneumonia-like illness in the city of Wuhanin China . They quickly determined that it was a coronavirus, and that it was spreading in and out of Wuhan.

Coronaviruses are common in all kinds of animals, and sometimes develop into infectious forms in humans. Since the turn of the century, two other coronaviruses have infected humans, causing the SARS outbreak in 2002 and MERS in 2012.

Scientists hope the new virus will first be able to jump to humans in early December. It first appeared to be infected with a seafood market in Wuhan and spread from there. An analysis of early cases of illness, published on January 24, found that the first patient who had the illness had nothing to do with the market. Experts are still trying to trace its spread.

It is not clear what kind of animal the virus originated from. A team of researchers in China has published a report stating that snakes are based on the genetic code of the virus. However, scientists are very skeptical of that decision. In another analysis, the genome sequence of the new virus is 96 percent identical to that of a coronavirus found in bats. Both SARS and MERS originate in bats.

So is this the same as SARS?

The new virus is not SARS, although it has also started in China. Since it comes from the same viral family as SARS, it has some similarities, but it is a completely new virus. However, the commonality is that scientists and public health officials can use what they have learned from past outbreaks.

China lied to WHO about SARS. Are they even lying about this?

During the SARS outbreak, Chinese officials tried to hide cases from WHO inspectors and limit information internally and externally. This time, officials quickly reported to the WHO the spread of the new virus, which praised their quick response and transparency at a press conference. On January 28, the company announced that China is allowing a team of WHO experts to assist Chinese public health officials with ongoing work.

The US Department of Health and Human Services also said that China is transparent compared to SARS. “China’s government cooperation is in stark contrast to what we experienced in 2003,” Department Secretary Alex Azar said at a press conference.

But critics and Chinese citizens remain skeptical: there are concerns that Chinese authorities are counting the number of illnesses and classifying deaths from the virus as pneumonia. Citizens of Wuhan Police are investigating the rumors online a few weeks ago.

How dangerous is this new virus?

Right now, nobody knows.

It takes information about how serious the illness is and how easily it can spread to find out how “bad” it is. Epidemiologists often use this tool to assess the new flu, and for example, guide decision making:

If the illness is not so severe (and only kills a small percentage), but it is highly infectious, it can still have devastating effects – if it affects millions, the small percentage that kills it will still result in a large number of deaths.

Researchers are still trying to understand the features of the coronavirus, which range from mild, to severe, to cold. According to the WHO, 20 percent of confirmed cases are severe. This is about 20 percent of cases we know – there are still very mild cases of non-flagged illness, which can reduce the percentage of serious cases.

So far, the mortality rate of the new coronavirus is between 2 and 3 percent, although it continues to vary as it spreads. The mortality rate in SARS is 14 to 15 percent. Most of the deaths in this outbreak are related to health problems such as heart disease, hypertension and diabetes in the elderly. (The same population at risk of dying from flu-like illnesses.)

How fast is the virus spreading?

We do not yet know how quickly or easily the virus can spread. In China, the WHO reports that people who have been infected have been infected by a person-to-person infection since early January, and that there have been chains of people who have passed on the virus for at least four generations: one person became ill (probably from an animal),

The virus was passed on to another person, who passed it on to another person. People in three countries outside China – Germany, Japan and Vietnam – have been infected with coronavirus by other people, and not from direct travel to China.

Other evidence suggests that, as with other coronaviruses, the virus jumps between people who are very close to each other and can spread when the infected person sneezes or coughs.

But Chinese officials say people who have the virus have seen cases of infection before they show symptoms. If this happens regularly, it is more difficult to contain the virus. There is still limited evidence that asymptomatic people can spread the virus. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said at a press conference that although it is happening, it will not significantly affect its spread. “Although there is some asymptomatic transmission, in the history of respiratory diseases, asymptomatic transmission has never been the cause of outbreaks,” he said. “The infection is not driven by asymptomatic carriers.”

The WHO said that the researchers believe that each sick person will be infected by an average of 1.4 and 2.5 additional people, but this is only a preliminary estimate. Teams of other researchers have published their own estimates, saying that the most sick person is, on average, two or three people infected.

Those numbers are called the virus’s R0 (pronounced “R-naught”). R0 is a mathematical representation of the extent of infection. The higher the number, the more likely it is to spread. For comparison, R0 for SARS is between two and five. But this does not mean that every sick person is actually infected by many; Restrictions and other measures taken to control the spread of the virus can reduce the number of infected people.

I have been coughing. Do I have this virus?

If you have not recently traveled to Wuhan, China, or have been ill and have been in contact with someone who recently moved to Wuhan, China, you are unlikely to get the virus. It is totally common to feel anxious – and there are ways to reduce that anxiety, such as by turning your attention to other activities, or by putting the risks in perspective.

If you live in the US, you are at risk of flu or colds. It is still flu season, and it is not expected that high levels of flu activity will ever die. (It’s not too late to get the flu shot!)

If you are feeling ill and moving to Wuhan, China, or in touch with someone who is, tell your doctor about your symptoms.

How can I protect myself?

Based on what we know so far, you can protect yourself with (and should) take steps to protect yourself from the flu: wash your hands, cover your mouth when you cough, and stay away from people who are sick.

Should I cancel a trip to China?

The U.S. Foreign Ministry has raised travel advisory to China to level 3, saying people should consider rerouting about traveling there. The section states that people should not go to Hubei Province and not to Wuhan Province. The CDC has issued a Level 3 warning that people should avoid unnecessary travel to China.

How is China trying to stop the virus?

On January 22, authorities in Wuhan shut down all transit in the city of more than 11 million people. They shut down buses and subways and canceled all flights and trains in and out of the city. The WHO Director-General praised the decision, saying it would help control the spread and slow the spread in other countries. Fifteen other cities with a total population of 46 million are also locked up, the New York Times reported.

However, other authorities do not know whether these restrictions are effective: “To my knowledge, trying to have a city of 11 million people is new to science,” China’s World Health Organization spokeswoman Gauden Galea told The Associated Press. “This has not been attempted as a public health activity. At this stage we cannot say we will or it will not work.

The virus has infected thousands of people in China and has spread to more than a dozen countries, including the US. Health minister Harsh Vardhan said on Tuesday that no virus cases have yet been confirmed in India.

*from various sources.