Doctors and scientists around the world are working to monitor, analyze and combat the emerging coronavirus, and yet we still do not know much of it three months after it first appeared in China.

Here are five basic questions that have not yet been answered with respect to the Covid-19 virus and the resulting global epidemic, as follows:

1- It varied from person to person

There is a wide variation in the severity of the symptoms of the disease among patients with it, so why does the emerging corona virus cause only minor symptoms or until it appears asymptomatic in 80% of those infected with it, while some patients provoke pneumonia that causes them within days ?

"Research conducted since last February shows that the clinical symptoms of this disease can be very differentiated," says Liu Boon of the College of Medicine in Hong Kong.

A Chinese study revealed that people who exhibit severe symptoms are "much older" than those with a slight infection, and that the concentration of the virus in samples extracted from the throat and nose scan is "about sixty times higher" than in other patient samples.

Is this due to a weaker immune response due to age, or as a result of an initial exposure to a higher amount of viruses?

2- Does the virus remain in the air?

The new Corona virus is known to be transmitted through physical contact and through the respiratory system. It can be caught, for example, through saliva droplets that a sick person throws around him when he coughs.

But does the virus remain suspended in the air, the immunologist and adviser to President Donald Trump, on the new Corona virus, Anthony Fawcci, answer: "We cannot completely rule out the idea that the virus is able to travel a certain distance in the air."

And an American study published in the "New England Journal of Medicine" showed that the new Corona virus could survive in the laboratory for three hours in the form of particles suspended in the air.

But it is not known whether this plays a role in the transmission of the disease. "Is the virus present in our surroundings?" Commented the head of the department of infectious diseases at Saint-Antoine Hospital in Paris, Karen Lacombe. Does it stay in the air or on the surfaces for a long time? This is what we do not know. We know we can find a trace of the virus, but we do not know if this virus transmits the infection. ”

3- The number of people infected with the virus

How many people are infected with the virus? This question applies to all of the Earth's seven billion inhabitants. How many of them are infected with the virus? With the exception of a few countries that have rapidly adopted a policy of early detection through large-scale intensive screening campaigns such as South Korea and Germany where half a million people can be examined a week, the known number of casualties remains almost largely.

For example, on March 17, the British government estimated the number of injuries at 55,000, while fewer than 2,000 people were confirmed through detection tests.

It is essential to know the exact extent of the epidemic in order to isolate HIV carriers and provide them with a good treatment.

In a second stage, it is important to monitor people who have contracted the virus and it can be assumed that they have acquired immunity to it.

This will be possible only with a new generation of tests, the serological tests that monitor the immune fingerprint left by the virus in the blood.

4- Is the virus affected by weather conditions?

Will the Covid-19 epidemic fade with better weather in the northern half of the Earth and disappear with the return of the heat? Experts say this is possible, but it is not certain. Seasonal influenza viruses are more stable in cold and dry weather, which enhances their transmission.

A study conducted by university professors in Hong Kong showed that the SARS virus that invaded Asia in 2002-2003 has caused the death of 774 people, and it is a strain of the currently spreading virus, which is stronger in low temperatures and weak humidity.

It is reasonable for some experts to assume that the two viruses have the same response to weather conditions.

But a recent study at Harvard Medical School in Boston concluded that "changing weather conditions alone will not necessarily lead to decreased Covid-19 injuries without taking severe health measures."

5- What is the secret of children

Children remain much less likely than adults to have a Covid-19 epidemic. If they develop symptoms, they will generally be as slight as those mentioned by a Chinese team in March in the journal Nature.

Of the ten children who were infected with the emerging coronavirus, which were studied, none had serious symptoms, but the symptoms were limited to sore throat, cough, and mild fever. This is most evident in children who reside with infected people, as they are two to three times less likely to become infected than adults. No one knows the reason for this, but the same was observed when the SARS virus spread in 2002-2003. "There are many things that we do not know, and so we have to show a lot of humility," said Karen Lacombe, summing up the situation.