Brief Answer:
Seems to be primarily immune mediated damage

Detailed Answer:
Hello,

Thanks for the query.

The SARS COV-2 or COVID 19 as it is widely known, belongs to a family of viruses called coronaviridae.

The lungs of humans are the main body part that is most affected with this infection.

It causes Diffuse alveolar damage with varying degrees of acute exudative features including edema and hyaline membranes, organization, and fibrosis.

Macrophagic or mixed cellular infiltration, multinuclear giant cells, atypical reactive pneumocytes, and vascular injury.

These are all the changes that are seen in infection with Coronavirus that is prevalent presently.

It does also affect other systems including the heart and lymphoid tissue.

In simpler words, virus attaches to the cells in our lungs, then it enters these cells and starts multiplying in those cells by hijacking the cell cycle of the host cell, the viral RNA and other particles pour out the host cell and are detected by our white blood cells which attack the infected cells and destroy them.

Which makes it difficult to breath because the surfactant that should be produced by the cells in our lungs is not produced in adequate amounts so we will develop breathlessness.

The damage also results in accumulation of fluid in the lungs which is detected as pneumonia.

Hope that answers your query.

Best regards

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