Scientists have discovered how the COVID-19 virus, SARS-CoV-2, causes damage to cells in our airways. When the virus infects our bodies, it uses a special protein called ACE2 to enter and attack the cells in our lungs. Once inside, the virus triggers a process called necroptosis, which is a type of cell death.

Necroptosis happens when the virus's RNA (a molecule similar to DNA) binds to a protein in our cells called ZBP1. This binding starts a chain reaction that makes the infected cell break apart and die. The study found that necroptosis is the main way cells die when infected with SARS-CoV-2.

Interestingly, different variants of the virus cause different levels of cell death. The Delta variant, known for causing severe illness, was found to trigger much more necroptosis compared to the Omicron variant, which is milder. This explains why Delta leads to more serious symptoms and more damage in the lungs.

Researchers also noticed that while infected cells mainly die through necroptosis, neighboring cells that are not directly infected often die through another process called apoptosis. This is a type of cell death where the cell safely breaks down without causing inflammation.

Understanding how SARS-CoV-2 causes cell death helps scientists develop better treatments to protect our lungs from severe damage during COVID-19. This study highlights the importance of controlling viral replication and targeting specific cell death pathways to reduce the severity of the disease.