Persistent SARS-CoV-2 infection in patients seemingly recovered from COVID-19

Area of Science:

• Pathology
• Virology
• Pulmonology

Background:

• Clinical presentation of SARS-CoV-2 infection is highly variable.
• Some patients experience disease progression and death despite initial recovery and negative viral tests.

Purpose of the Study:

• To investigate persistent SARS-CoV-2 infection and associated lung pathology in patients with apparent recovery but progressive disease.

Main Methods:

• Post-mortem analyses of 27 patients with a history of COVID-19 and progressive clinical decline.
• Histopathological examination of lung tissue.
• Immunohistochemistry for viral antigens and antibodies.
• Quantitative RT-PCR for viral RNA detection.

Main Results:

• 81% of patients showed interstitial pneumonia, with 47% exhibiting extensive fibrosis.
• Lung pathology resembled acute COVID-19, including vascular thrombosis (67%) and syncytia (67%).
• SARS-CoV-2 RNA was detected in lung tissue lysates, and viral antigens were found in bronchial cartilage chondrocytes and glandular cells (70%).

Conclusions:

• SARS-CoV-2 can persist in specific lung cell types for extended periods, beyond standard PCR detectability.
• Persistent infection may contribute to long-term lung damage and disease progression.
• The role of these persistently infected cells in long COVID requires further investigation.