What cells are affected by the Spanish flu?

The Spanish flu primarily affected the cells of the respiratory system, namely the cells lining the airways and lungs. The virus responsible for the pandemic, known as the influenza virus, has a particular affinity for cells in the trachea, bronchi, and alveoli. Once inside these cells, the virus replicates rapidly, causing inflammation and damage, leading to the symptoms characteristic of the Spanish flu, such as fever, cough, shortness of breath, and in severe cases, pneumonia.

Specifically, the Spanish flu virus targets type II pneumocytes, which are important for producing surfactant, a substance that helps the lungs expand and contract properly. The infection and destruction of these pneumocytes disrupt the normal exchange of oxygen and carbon dioxide, leading to respiratory distress and potentially life-threatening complications.

Besides respiratory cells, the Spanish flu virus could also affect other organ systems, although to a lesser extent. In some cases, the virus was found to cause systemic involvement, leading to damage in organs such as the heart, kidneys, and brain.