COVID-19. Etiology, pathogenesis, diagnosis and treatment

Abstract

COVID-19 is a new epidemic infectious disease characterized by a relatively high contagiousness and the likelihood of life-threatening complications in the form of acute respiratory distress syndrome (ARDS), acute respiratory and multiple organ failure. The causative agent of the disease is the enveloped zoonotic RNA virus SARS-CoV-2 belongs to the Coronaviridae family, the genus Betacoronavirus, as well as the previously known SARS-CoV and MERS-CoV viruses, which cause severe acute respiratory syndrome and the Middle East respiratory syndrome, respectively. The virus is transmitted by air and contact routes, therefore, to protect medical personnel it is necessary to use individual protective suits and accessories, with protection of the respiratory tract and eyes, disinfection of hands and surfaces as when working with microorganisms of the I-II pathogenicity group. The diagnosis of COVID-19 is confirmed using real-time RT-PCR diagnostics that detect the presence of viral RNA. The clinical manifestations of COVID-19 vary from mild to moderate, to severe and extremely severe (5% of cases, ARDS, multiple organ failure, mechanical ventilation and resuscitation are necessary). The clinical picture of acute respiratory viral infections with severe fever, dry cough, respiratory failure, against the background of lymph and thrombocytopenia, normal procalcitonin, elevated levels of ferritin and CRP in the blood with signs of bilateral, polysegmental pneumonia and the phenomenon of "frosted glass" on CT, even in the absence of an unfavorable epidemiological An anamnesis makes it possible to diagnose COVID-19 with a high degree of probability and hospitalize the patient in an infectious isolation ward, without waiting for the results of PCR diagnostics. There is no specific etioptropic therapy for COVID-19; the only method that has proven effective in limited clinical trials is plasma infusion of convalescents with a high titer of neutralizing antibodies. High hopes are pinned on innovative treatments, such as the creation of neutralizing monoclonal antibodies and cell therapy using MSCs or NK cells. The first SARS-CoV-2 vaccine, mRNA-1273, is currently undergoing clinical trials.