ABSTRACT COVID-19 (coronavirus disease 2019) is an infectious disease caused by the new coronavirus associated with severe acute respiratory syndrome 2 (SARS-CoV-2). Coronaviridae comprises a large family, of which at least seven members are known to cause respiratory diseases in humans. Coronaviruses have the ability to infect virtually all major groups of animals and, eventually, can infect humans. SARS-CoV-2 is the third coronavirus to cross the species barrier and infect humans. This virus was identified in an outbreak of pneumonia cases in Wuhan city, Hubei province, China, in December 2019. Its entire genome is inscribed on a single strand of ribonucleic acid. Some proteins present on the surface of the virus act as facilitators for its entry into host cells, while others, apparently, are related to its pathogenesis. Coronaviruses are responsible for respiratory infections in humans and some animals. The infection is often mild to moderate in intensity, but some coronaviruses may cause serious illnesses, such as severe acute respiratory syndrome (SARS), which occurred in 2002, and the Middle East respiratory syndrome (MERS). Coronaviruses can activate an excessive and unregulated immune response, which may promote SARS development. Although the lungs are one of the target organs, the hypoxia mechanism is systemic and other organs begin to suffer both through lack of oxygen and through deregulation of inflammation control mechanisms.

COVID-19 (coronavirus disease 2019) is an infectious disease caused by the new coronavirus associated with severe acute respiratory syndrome 2 (SARS-CoV-2). Coronaviridae comprises a large family and at least seven members are known to cause respiratory diseases in humans. Coronaviruses have the ability to infect virtually all major groups of animals and, eventually, can infect humans. SARS-CoV-2 is the third coronavirus to cross the species barrier and infect humans. This virus was identified in an outbreak of pneumonia in the city of Wuhan, Hubei province, China, in December 2019. Its entire genome is inscribed on a single ribbon of ribonucleic acid. Some proteins present on the surface of the virus act as facilitators of its entry into host cells, others, apparently, are related to its pathogenesis. Coronaviruses are responsible for respiratory infections in humans and some animals. The infection is often mild to moderate in intensity, but some coronaviruses can cause serious illnesses, such as Severe Acute Respiratory Syndrome (SARS) (SARS), which occurred in 2002 and the Middle East respiratory syndrome. (MERS, from Middle East respiratory syndrome). Coronaviruses can activate an excessive and unregulated immune response, which can promote SRAG development. Although the lung is one of the target organs, the hypoxia mechanism is systemic and other organs suffer both the lack of oxygen and the disruption of inflammation control mechanisms.

COVID-19 (do inglês coronavirus disease 2019) é uma doença infecciosa causada pelo novo coronavírus associado à síndrome respiratória aguda grave 2 (SARS-CoV-2). Coronaviridae compreende uma grande família e, pelo menos, sete membros são conhecidos por causarem doenças respiratórias em humanos. Os coronavírus têm a capacidade de infectar praticamente todos os principais grupos de animais e, eventualmente, podem passar a contaminar humanos. O SARS-CoV-2 é o terceiro coronavírus a transpor a barreira entre espécies e infectar humanos. Esse vírus foi identificado em um surto de casos de pneumonia na cidade de Wuhan, província de Hubei, China, em dezembro de 2019. Todo o seu genoma está inscrito em uma fita única de ácido ribonucleico. Algumas proteínas presentes na superfície do vírus atuam como facilitadores do seu ingresso nas células hospedeiras, outras, aparentemente, estão relacionadas com a sua patogenia. Os coronavírus são responsáveis por infecções respiratórias em seres humanos e em alguns animais. Frequentemente, a infecção é de intensidade leve a moderada, mas alguns coronavírus podem causar doenças graves, como a Síndrome Respiratória Aguda Grave (SRAG) (SARS, do inglês Severe Acute Respiratory Syndrome), que ocorreu em 2002 e a síndrome respiratória do Oriente Médio (MERS, do inglês Middle East respiratory syndrome). Os coronavírus podem ativar uma resposta imune excessiva e desregulada, a qual pode propiciar o desenvolvimento SRAG. Ainda que o pulmão seja um dos órgãos alvo, o mecanismo de hipóxia é sistêmico e outros órgão passam a sofrer tanto a falta de oxigênio quando a desregulação dos mecanismos de controle da inflamação.