Déjà Vu All over Again

In late 2019, an acute, severe lower respiratory tract illness of unknown etiology, linked to contact with a live seafood and animal market, was reported in Wuhan City, Hubei Province, China, subsequently shown to be caused by a novel coronavirus termed the Severe Acute Respiratory Syndrome (SARS) Coronavirus (CoV)-2. The infection caused by this virus is referred to as coronavirus disease 2019, or COVID-19. SARS-CoV-2 infects human cells through binding of viral surface spike protein to human angiotensin-converting enzyme 2 receptors, predominantly expressed on Type II alveolar cells, in the lung. SARS-CoV-2 is highly transmissible, and affected patients can transmit the infection while asymptomatic. Patients commonly complain of fever, dry cough, fatigue, myalgias, headache, and dyspnea. Most infected patients have mild disease and recover, with more severe disease and mortality more commonly present in older individuals and patients with comorbidities, such as hypertension, diabetes, and chronic cardiovascular and respiratory conditions. The diagnosis of COVID-19 is typically established through identification of viral nucleic acid at real-time reverse transcriptase polymerase chain reaction on respiratory tract samples. Chest radiography in COVID-19 infection may be normal; when abnormal, patchy areas of lower lobe ground-glass opacity and/or consolidation are seen. Computed tomography is more sensitive than chest radiography for detection of the infection and commonly shows multifocal, bilateral, peripheral, and basal predominant round or oval areas of ground-glass opacity that may subsequently transition to consolidation. Treatment for COVID-19 is currently supportive, with various ongoing trials evaluating a number of potentially therapeutic agents.