COVID-19: Coronavirus replication, pathogenesis, and therapeutic strategies
Cornelia C. Bergmann, Robert H. Silverman
Abstract
H uman coronaviruses, along with in- fl uenza virus, human metapneumovirus, respiratory syncytial virus, and rhinovirus, are endemic and cause approximately 15% to 30% of annual respiratory tract infections. Coronavirus infections are generally mild in healthy adults, obviating any urgent need to develop treatments or vaccines. However, outbreaks of acute respiratory distress syndrome (ARDS) due to novel, highly pathogenic strains-severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and now, SARS-CoV-2-have revealed the potency and danger of this expanding family of pathogens that have the capacity to kill many thousands of people around the world if not geographically contained. s in severe SARS and MERS disease, the mortality rate is disproportionately high in the elderly and patients with preexisting comorbidities such as heart disease, diabetes mellitus, hypertension, and renal disease. 2 Higher morbidity in the elderly may partly be attributed to muted interferon antiviral responses (although the suggestive study has not yet been peer-reviewed) 3 as well as overall lower adaptive immunity, 2 resulting, paradoxically, in longer courses of hyperactivity of the innate immune system ("cytokine storm").