How does Covid-19 infect lung cells? Why is it so dangerous?
Not just one, but millions of viruses will be synthesized in each lung cell.
Last week, the World Health Organization (WHO) officially declared Covid-19 a global pandemic. The disease caused by a strain of corona virus called SARS-CoV-2 has now infected more than 167,000 people in more than 100 countries. 6,506 of them died.
Scientists say the SARS-CoV-2 virus strain is dozens of times more dangerous than seasonal flu. Sharing the same features and structure as the SARS virus that caused the 2003 acute respiratory infection pandemic, but SARS-CoV-2 is even "wiser" to choose a strategy of widespread infection with a high mortality rate. low mortality.
The SARS outbreak in 2003 with a mortality rate of over 10% quickly made the SARS virus extinct as it killed most of the people who got it and left no host for transmission. Meanwhile, SARS-CoV-2, which only causes a death rate of about 3%, is still raging around the world.
So what are the characteristics, the weapons that this virus uses to infect people? Let's find out in the article below:
Virus SARS-CoV-2
That is the official name of the new strain of corona virus that is causing the global Covid-19 pandemic. In addition to this virus strain, we know at least 6 other strains of corona virus that infect humans. Some strains of corona only cause the common cold. But there are two other corona strains that, in the past, have caused serious epidemics, SARS and MERS.
The thorns surround the virus
In English, "corona" means "crown". Viruses are named corona because the protein spikes protrude from their surface, forming a shape similar to crowns.
In addition to the outermost spine, the SARS-CoV-2 virus also has a membrane containing lipid molecules. When these molecules come into contact with soap, they dissolve and cause the viral spikes to fall off.
Alcohol-based hand sanitizers also work on the same principle, alcohol destroys the lipid membrane of viruses, thereby making them lose their spines and become inactivated.
As long as SARS-CoV-2 retains its spikes, they can still infect the inside of host cells.
Infiltrate a vulnerable cell
The SARS-CoV-2 virus infects the body through the nose, mouth, or eyes. It then attaches its spikes to a receptor called ACE2 to enter the cell. ACE2 receptors are highly concentrated on the surface of lung cells. Therefore, this virus causes acute pneumonia.
In addition to lung cells, ACE2 receptors are also present in the intestines, kidneys, testes, and heart. However, the strange thing is that the SARS-CoV-2 virus does not attack the heart of the patient.
But some fertility experts in China have recommended that Covid-19 patients who have recovered and are discharged from the hospital should still have their reproductive health checked to make sure it doesn't leave any sequelae on the testicles and testicles. their insect.
Release viral RNA
The virus infects cells by combining its oil membrane with the lung cell membrane. Once inside, SARS-CoV-2 releases a piece of its genetic material called RNA.
Manipulating lung cells
RNA is the entire genome of SARS-CoV-2. It has about 30,000 genetic characters. In comparison with humans, we have up to 3 billion. But after the virus releases the RNA into the lung cells, our cells read these RNA codes because they think it's theirs.
Our lung cells then make proteins that block our own immune system against pathogens. At the same time, it helps the virus assemble and synthesize identical RNA fragments. This is how viruses make new copies and multiply.
Antibiotics kill bacteria and have no effect against viruses. But researchers are testing antiviral drugs that can inhibit or break down viral proteins and prevent them from taking over our lung cells.
Producing proteins for viruses
Not only does the RNA synthesis for the SARS-CoV-2 virus, as the infection progresses, the lung cell machinery also helps them produce new spikes and other proteins. Eventually, it will all be reassembled into millions of replica viruses.
This is how virus copies are assembled in host cells
So another virus was born. There is not one, but millions of them in every lung cell.
Continue to infect
Each lung cell after infection with SARS-CoV-2 can continuously release millions of copies of the virus, before they burst and die. The newly released virus pool continues to infect nearby lung cells, which have ACE2 receptors, and repeat the same cycle.
Immune response
Most Covid-19 infections have a febrile response as the immune system fights to clear the virus. In severe cases, the immune system can overreact and start attacking even healthy lung cells.
Gradually, the patient's lungs will become congested due to the fluid flowing out in the lungs and dead cells. The patient will therefore present with shortness of breath. A small percentage of patients may develop severe respiratory failure in the process, leading to death.
Leaving the body
When an infected person coughs and sneezes, they can expel virus-filled droplets to another person or nearby surfaces. On these surfaces, the SARS-CoV-2 virus can survive from a few hours to a few days waiting for the opportunity someone touches, then touches their eyes, nose, or mouth.
The virus will then infect the new patient again. To prevent the virus from spreading through droplets, people infected with Covid-19 should wear a mask.
Research on vaccines against Covid-19
A future vaccine could help the body make antibodies that target the SARS-CoV-2 virus and prevent it from infecting human cells.
The flu vaccines that we have now work in a similar way, but the antibodies produced by the flu vaccine cannot protect lung cells from the SARS-CoV-2 virus.
Please wash your hands with soap
Soap kills SARS-CoV-2 when the tails of the soap molecules attach to the viral lipid membrane and rip it apart.
The best way to avoid catching Covid-19 and other viral illnesses is to wash your hands with soap, avoid touching your face, keep your distance from sick people, and regularly clean potentially germ-carrying surfaces. .
Nguồn: Tri Thức Trẻ