Disclaimer: Not medical or professional advice. Always seek the advice of your physician.
SARS-CoV-2. SARS-CoV-2 is an official name of the virus that caused the pandemic. It is often called a novel COVID-19 because the virus was not known before. If you decipher the abbreviation, you will get Severe acute respiratory syndrome-related coronavirus 2. The digit 2 means that the first was SARS, which caused the atypical pneumonia outbreak in 2002.
COVID-19 is an infectious disease caused by the SARS-CoV-2 coronavirus. COVID-19 is an abbreviation for COVID-19 disease, and the number 19 in the name indicates the year the virus appeared.
This is the most widespread method of transmission. It is almost impossible to get sick with COVID-19 on the street, but the danger increases indoors. That is why doctors recommend wearing masks without fail, especially for those who are already sick. The barrier will protect others from saliva particles when coughing, sneezing, and even during simple conversation. In most cases, people experience mild or asymptomatic course of the disease. And it is these people who become carriers of the potentially fatal disease.
This means: through things and surfaces on which the virus remains after contact with a sick person. The infected person coughs reflexively covering his mouth with his hand. Then he touches things in a store or doorknobs in the office, presses the button to call the elevator. A healthy person does the same things, and then touches his face with his hands —he scratches his nose, rubs his eyes. The virus enters the mucous membrane and infection begins.
This is another reason to refuse to shake hands during the pandemic. Even if you greet a healthy person, this does not at all guarantee that he has not come into contact with fomites. And do not forget to regularly wipe your mobile phone with alcohol wipes: you use it on the street, in shopping centers and public transport, infected particles are easily deposited on it, and on plastic COVID-19 can remain viable for up to several hours.
After about 3-4 months, the number of antibodies in those who had a mild or moderate COVID-19 decreases, so the person can get sick again. And those with more severe illness enough antibodies develop to protect the body from infection for a longer period.
One of the important epidemiological indicators is the basic reproduction number, which helps to predict the extent of infection.
The basic reproduction number shows the number of people that one sick person can infect around him. For example, the basic reproduction number for influenza is 1-2, for measles it is 12-18.
For COVID-19 (according to Chinese epidemiologists) — about 4. Thus, we can conclude that the COVID-19 is 3-4 times less infectious than measles and 2-3 times more infectious than influenza.
So far, the period when a person begins and ends to be dangerous to others has not been precisely defined. But data from some studies indicate that a person with COVID-19 is able to spread the virus before any symptoms appear (1-3 days before the first signs of illness). People are considered the most contagious at the time when the incubation period ends and symptoms of the disease appear.
The duration of virus shedding depends on the severity of the disease. In practice, if the patient was in the hospital, then he is considered healthy after two negative tests for COVID-19. When passing a home treatment, three conditions must be met.
In February 2020, Chinese scientists published a report that analyzed more than 70,000 cases of COVID-19. This is the largest study by the moment.
The statistics from this study are as follows.
Research data distinguish the following diseases into the main high-risk group for a severe course of COVID-19 infection.
The course of COVID-19 is significantly aggravated by autoimmune and oncological diseases.
Usually the first symptoms of COVID-19 appear 5-6 days after contact with the infected. But they can appear in a day or in two weeks.
The most common symptoms are.
Less common.
It is not yet known exactly how long the virus remains in the body but the Centers for Disease Control and Prevention advise to stay at home for 10 days after symptoms appear.
With COVID-19, the main symptoms are fever, dry cough and weakness. The loss of smell and taste is also a characteristic symptom. With flu, the most common symptoms are high fever, muscle aches, chills, headache and weakness. Cough occurs occasionally, shortness of breath is rare, and taste and smell do not change.
As a rule, the COVID-19 symptoms are mild and appear gradually, and with the flu, they appear suddenly.