Human endogenous retrovirus K activation in the lower respiratory tract of severe COVID-19 patients associates with early mortality.by Thiago Souza et al.
Critically ill 2019 coronavirus disease patients (COVID-19) under invasive mechanical ventilation (IMV) are 10- to 40-times more likely to die than the general population. Although progression from mild to severe COVID-19 has been associated with hypoxia, uncontrolled inflammation and coagulopathy, the mechanisms involved in progression to severity are poorly understood. By analyzing the virome from tracheal aspirates (TA) of 25 COVID-19 patients under IMV, we found higher levels and differential expression of human endogenous retrovirus K (HERV-K) genes compared to nasopharyngeal swabs from mild cases and TA from non-COVID patients. Proteomic analysis and RT-PCR confirmed the presence of HERV-K in these patients.