What happens in the body after infection with coronavirus: a step-by-step

As soon as a pandemic of 2019 coronavirus-nCoV is distributed in the United States, leading to the cancellation of major events, closure of schools, the collapse of the stock market and the disturbances in the flow of everyday life, Americans take precautions against coronavirus infection, causing illness and death of thousands of people around the world, writes USA Today.

Что происходит в организме после заражения коронавирусом: шаг за шагом

Photo: Shutterstock

The world health organization and the US Centers for control and disease prevention recommend that people pay attention to fever, dry cough and shortness of breath — symptoms that follow infection with the novel coronavirus that causes the disease COVID-19.

From the appearance of the infection to onset of symptoms is approximately 5 to 12 days. Here is a step-by-step look at what happens inside the body when the virus is fixed.

Coronavirus infection

According to the CDC, the virus can be spread from person to person within 6 feet (nearly 2 meters) through droplets formed when the infected person coughs or sneezes.

It is also possible that the virus will remain on the surface or object, will be transferred by contact and enters the body through the mouth, nose or eyes.

Dr. Martin Hirsch, a senior physician in the Service of infectious diseases at Massachusetts General hospital, said that about a new virus we will learn a lot, but experts suspect that the 2019 coronavirus-nCoV can act the same way as behaved virus SARS-CoV 13 years ago.

“It’s a respiratory virus, and therefore it penetrates through the respiratory tract — we think primarily through the nose,’ said the doctor. But it can penetrate through the eyes and the mouth, because so behave other respiratory viruses.”

When the virus enters the body, it begins its attack.

Fever, cough and other symptoms COVID-19

According to Hirsch, human symptoms may occur within 2-14 days after initial exposure to the virus. On average, this occurs after 5 days.

Once inside the body, it begins to infect epithelial cells in the mucosa of the lungs. Protein receptors on the virus can attach to receptors on host cell and to penetrate into the cell itself. Inside the host cell the virus begins to multiply until they kill the cell.

It first occurs in the upper respiratory tract which include nose, mouth, throat and bronchial tubes.

The patient begins to experience mild version of the symptoms: dry cough, shortness of breath, fever and headache, muscle pain and fatigue comparable to signs of flu.

Dr. Pragya of Dhaubhadel and Dr. Amit Munshi Sharma, infectious disease specialists at Geisinger, say that some patients have reported gastrointestinal symptoms such as nausea and diarrhea, but it is a relatively rare occurrence.

Symptoms become more severe when the infection starts to penetrate into the lower Airways.

Pneumonia and autoimmune diseases

Who reports that in February, about 80% of patients sick COVID-19 in mild or moderate form. The “easy” cases include fever and cough are more severe than for seasonal influenza, but did not require hospitalization.

These lighter cases due to the fact that the immune response is able to keep the virus in the upper respiratory tract, says Hirsch. Younger patients have stronger immune response compared with older patients.

13.8% of severe cases and 6.1% of the critical cases related to the fact that the virus penetrates the lower airway, where, apparently, it begins to grow.

“Light is the main goal,” said Hirsch.

According to Dr. Rafael Viscidi, a specialist in infectious diseases at Johns Hopkins Medicine, as soon as the virus continues to multiply and extend beyond the airway and into the lungs, it can cause more severe respiratory diseases such as bronchitis and pneumonia.

Pneumonia is characterized by shortness of breath combined with coughing and affects the tiny air sacs in the lungs called alveoli, said Viscidi. In the alveoli the exchange of oxygen and carbon dioxide.

When there is pneumonia, a thin layer of alveolar cells damaged by the virus. The body responds by sending immune cells in lungs to fight him.

“And this leads to the fact that the shell becomes thicker than normal, he said. — As soon as cells are gathering more and more, they are, in fact, stifle a small air pocket, and this is what you need to get oxygen to the blood.”

“So basically it’s a war between reaction and virus, said Hirsch. — Depending on who wins this war, we have either good results, when patients recover, or poor results when they do not.”

The restriction of oxygen that leaves no important organs, including the liver, kidneys and brain.

In a small number of severe cases this may develop into acute respiratory distress syndrome (ARDS), which requires placement of the patient to the ventilator (artificial lung ventilation) for oxygen supply.

However, if too much of the lungs are damaged and not enough oxygen goes to the rest of the body, respiratory distress can lead to organ damage and death.

Viscidi emphasizes that the outcome of the disease — a rarity for the majority of patients infected with the coronavirus. The most susceptible to serious disease people over the age of 70 with weak immune reactions. Other risk groups include people with lung problems, chronic diseases or compromised immune systems such as cancer patients who received chemotherapy.

Westside encourages people to think about the coronavirus as the flu because the virus goes through the same process in the body. Many people get the flu and recover without complications.

“People should remember that they are as healthy as they feel themselves to be, he said. — You should not feel unhealthy to such a degree that dictates fear.”


Educational program



Special projects