Definition. Coronaviruses are a family of RNA-containing viruses, including on January 2020 40 species that infect humans and animals. The name is associated with the virus structure, the spine-shaped processes of which resemble the crown. Coronaviruses can cause illnesses from the common cold to severe acute respiratory syndrome.
1937 - coronavirus was first isolated in chickens;
1965 - the first human coronavirus was isolated (4 strains in total);
2002 - The First Pandemic of the twenty-first century began in southern China in the province of Guangdong, where live more than 75 million people. The population of the province is mainly employed in the agricultural sector. Numerous farms specialize in breeding wild animals - raccoon dogs, Chinese badger ferrets, and spotted mammals from the cat family, which are used to prepare delicacies added to food and in the manufacture of perfumes - the musk solution obtained from them is used in the perfume industry (Arabic zabad);
2012 - Middle East respiratory syndrome was diagnosed in Saudi Arabia, one-humped camels were the source of infection, from which the coronavirus was transmitted to people, that is, a new human strain was formed from the zoonotic virus;
Since 2012, cases of the Middle East respiratory syndrome have already been reported in 27 countries, WHO convened three meetings of the Committee on Emergency Situations, where it was decided that this situation is not yet an emergency in the field of public health of international importance;
2015 - The WHO Emergency Committee emphasized that despite the fact that three years have passed since the occurrence of the Middle East respiratory syndrome in humans has been recognized, the global community remains in the grip of this new infectious disease. In some countries, transmission of the virus from camels to people continues, and cases of transmission from person to person in medical facilities continue;
In December 2019, an outbreak of pneumonia caused by a freshly discovered virus began in China.
The mechanism of damage. Coronaviruses have a very specific way of penetration into cells, which reduces the effectiveness of the usual protection of cell membranes against viruses. The Corona is equipped with S-proteins that mimic molecules important for the life of cells. The "deceived" transmembrane receptors pass a fake molecule inside. Inside the cell, the virus replicates and creates many of its own copies, which are released from the infected cell destroying it. You can only “deceive” old, weak, diseased and insolvent cells, therefore, the risk of infection increases in the elderly, in people with chronic diseases, especially the respiratory system, with a decrease in immunity, and also in the changed ecological environment of the metropolis.
Possible transmission mechanisms: airborne, airborne dust, fecal-oral, contact. The incidence increases in winter and early spring, which coincides with seasonal exacerbations of diseases and a decrease in immunity in weakened people. In the general structure of acute respiratory viral infections of hospitalized patients, coronavirus infection averages 12%. Immunity after a short illness, as a rule, does not protect against reinfection, which is associated with the high ability of the coronavirus to mutate and the “corona”, which reduces the effectiveness of the usual protection of cell membranes against viruses. The widespread prevalence of coronaviruses is indicated by specific antibodies found in 80% of people. Some coronaviruses are contagious before clinical symptoms appear.
It is believed that about 30% of acute colds in humans are associated with the colonization of coronavirus in the epithelial cells of the nasal mucosa and trachea. The main clinical manifestation of acute colds caused by human coronavirus is acute rhinitis, tracheitis. It was believed that coronavirus does not cause damage to the lower respiratory tract. E.O. Balkarova with co-authors (1996–98) at the Institute of Pulmonology of the Ministry of Health of the Russian Federation were investigated viral dysbiosis in patients with atopic syndrome: bronchial asthma, allergic rhinitis, atopic dermatitis. The authors found that more than a quarter of patients with atopic syndrome show positive antigenemia (antigens to coronavirus in the blood) and specific antibodies to the first serotype of coronavirus were detected. In addition to coronavirus, patients also showed persistence of rotavirus and adenovirus, but carriage of coronavirus prevailed. The established fact of viral dysbiosis prompted further studies, the purpose of which was to establish a causal relationship between the mechanisms of atopy and persistence of the coronavirus (A.G. Chuchalin, Breast Cancer, No. 22, 22/11/2003).
Incidence. Age categories from 0 to 10 years and from 10 to 19 account for 1% of cases (Overview of the Center for Disease Control and Prevention of the PRC).
The clinical picture of the disease also depends on age. Acute onset, severe complications and high mortality were characteristic of older people. After the age of 65, mortality reached 40%, while in the general population it was 5–8%, i.e. the same indicators that doctors meet when managing patients with acquired pneumonia.
The most vulnerable to coronavirus infection are people with lung diseases (chronic bronchitis, bronchial asthma, etc.), severe chronic diseases (hypertension, cardiac ischemia, diabetes mellitus), with various forms of immunodeficiency: HIV-infected, cancer patients and patients after organ transplantation.
The original article was published on the website of the Breast Cancer (Russian Medical Journal).
The clinical manifestations of the disease are determined by the weakest link in the body:
gastrointestinal mucous membranes;
organs of life support systems - liver, kidneys, lymphatic system, heart, blood vessels;
manifestations of intoxication - tissue destruction;
manifestations of secondary infection;
symptoms of exacerbation of chronic diseases.
As it turned out, about half of the patients in the Wuhan hospital who were diagnosed with coronavirus had chronic diseases.
To determine the trigger, do tests. About 30% of the examined are carriers, without any clinical symptoms.
Complications. They are determined by the history of the person’s disease, the state of immunity, the existing chronic diseases and the history of treatment, hormonal preparations and long-term use of antibiotics are especially important, which cause the progression of viral-bacterial infection and stimulate the growth of fungal flora in the body, in particular, in the lungs.