Five months later, scientists now know about the coronavirus | World News

Coronaviruses have been causing problems for mankind for a long time. Several versions are known to cause common colds, and recently two types of severe acute respiratory syndrome (Sars) and the Middle East respiratory syndrome (Mers) have caused fatal disease outbreaks. Is causing.

However, their effects were mild compared to the global upheaval released by the coronavirus causing the Covid-19 pandemic. In just a few months it caused lockdowns in dozens of countries and claimed More than 100,000 lives. And the disease continues to spread.

This is an extraordinary result of a genetic material spiked bowl with a diameter of 1/8 billion meters, coated with a fatty chemical called lipid. Humanity has been lowered by very humble perpetrators.

On the other hand, our knowledge of Sars-CoV-2, the virus that causes Covid-19, is also notable. This was an unknown creature five months ago. Today, this is the subject of research on an unprecedented scale. Vaccine projects soared, Antiviral drug testing has begun and new diagnostic tests are emerging.

Therefore, the question is straightforward. What have you learned in the last five months, and how can that knowledge end this pandemic?

Where did it come from and how did it first infect humans?

Sars-CoV-2 virus almost certainly Derived from bats, Researchers have evolved a violent immune response to the virus. These defenses allow the virus to replicate faster and pass through the bat’s immune defenses. Then it bats Rapidly breeding, highly contagious storage Virus. Then, when these bat viruses move to other mammals, that is, organisms that do not have a fast responding immune system, the virus quickly spreads to new hosts. Most evidence suggests that Sars-CoV-2 has begun to infect humans via intermediate species such as pangolins.

“This virus probably jumped from a bat to another animal, and other animals were probably near humans and probably on the market,” says virologist Edward Holmes of the University of Sydney. “In other words, if the wild animal has the virus, it is picked up from the bat and if we interact with the virus, the virus is more likely to spread to the person who is dealing with the animal. Then he goes home and spreads it to others, and we have a big outbreak. “

Regarding the transmission of Sars-CoV-2, it occurs when an infected person discharges water drops containing the virus by coughing or sneezing.

How are viruses spread and how do they affect people?

Particles infected by the virus are inhaled by others and come into contact with cells that cover the throat and larynx. On the surface of these cells are a number of receptors called Ace-2 receptors. (Cell receptors play an important role in passing chemicals to cells and triggering signals between cells.) “This virus has a surface that immobilizes its receptors and slides RNA into cells. There are proteins, “says virologist Jonathan Ball. Nottingham University.

Once inside, the RNA is inserted into the cell’s own replication machinery, creating multiple copies of the virus. They rupture from the cells and spread the infection. Antibodies produced by the body’s immune system eventually target the virus and, in most cases, stop its progression.

“Covid-19 infections are generally mild, which is the key to the success of the virus,” Ball adds. “Many people aren’t even aware of the infection, so they avoid having their jobs, homes, and supermarkets infected with others.”

In contrast, this disease, caused by a coronavirus-caused virus, significantly worsens the condition of the patient and kills about one in ten infected patients. In most cases, these patients are hospitalized and cutting the route of infection will prevent transmission to other patients. Milder Covid-19 avoids that problem.

Why do viruses sometimes cause death?

However, viruses can cause serious problems. It occurs when it travels down the airways and infects the lungs, which are richer in cells with Ace-2 receptors. Many of these cells are destroyed, and small pieces of the destroyed cells fill the lungs. In these cases, the patient needs intensive care.

Worse, in some cases, the human immune system is overworked, attracting cells to the lungs and attacking the virus, causing inflammation. This process goes out of control, injects more immune cells, and exacerbates inflammation. this is, Cytokine storm. (In Greek, “cell” means cell and “kino” means movement.) In some cases, this can kill the patient.

It is unknown why cytokine storms occur in some patients but not in the majority. One possibility is that some people have a version of the Ace-2 receptor that is slightly more vulnerable to attack from the coronavirus than most people.

Will my life be protected if I get infected?

Doctors examining patients who have recovered from Covid-19 infection have found fairly high levels of neutralizing antibodies in the blood. These Antibodies are made by the immune systemAnd they coat the invading virus at specific points, blocking its ability to invade cells.

“It’s clear that the infected people have a growing immune response to Covid-19,” says Mike Skinner, a virologist at Imperial College London. “And the antibodies generated by that response provide protection against future infections-but it should be noted that this protection is unlikely to last a lifetime.”

Instead, most virologists believe that immunity to Covid-19 lasts only 1-2 years. “It is consistent with other coronaviruses that infect humans,” says Skinner. “That means that even though most people are eventually exposed to the virus, they are more likely to become endemic, so there is a seasonal peak in the transmission of this disease. Has been reached. “

In short, the virus will be with us for a while. But can it change its toxicity? Some researchers have suggested that it may be less fatal. Others have argued that it could mutate and be more deadly. Skinner is suspicious. “We need to consider this pandemic from a virus perspective,” he says. “It’s spread very well all over the world. All right. So why do we need to change it?”

Ultimately, what frees us from the threat of Covid-19 is the development and deployment of effective vaccines, says Skinner.

When do you get a vaccine?

Friday, Journal Nature 78 vaccine projects Released worldwide, 37 more were developed. Among the ongoing projects are vaccine programs that are currently undergoing Phase 1 trials at Oxford University, two others with U.S. biotechnology companies, and three with Chinese science groups. I am. Many other vaccine developers say they will begin testing humans this year.

This amazing reaction Hope Covid-19 vaccine is developed In a fairly short time. However, vaccines require extensive safety and efficacy studies. Thousands of people have received either the vaccine itself or a placebo and have determined whether the former was effective in preventing transmission from naturally occurring viruses. It is inevitably a long process.

As a result, some scientists have proposed ways to speed up the process by intentionally exposing volunteers to the virus to determine the effectiveness of the vaccine. “This approach is not without risks, but it could push vaccine candidate trials months ahead of time,” says Nir Eyal, a professor of bioethics at Rutgers University.

He emphasizes that volunteers will need to be young and healthy: “Their health will also be closely monitored and intensive care and available medicines will be available.” As a result, the standard phase It could be used in much less time than vaccines tested in 3 and could potentially save millions of lives.

However, people who are intentionally infected, especially volunteers who are given a placebo vaccine as part of a trial, are controversial. “This needs to be considered very carefully,” says Professor Adam Finn of the University of Bristol. “Youth may jump at the opportunity to participate in such a trial, but this is a virus that kills weird youth. I don’t know why yet, but the Phase 3 trial is still a bit late, We have time to consider it carefully. “