system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If the flu symptoms that make us "sick" are reactions from our body fighting it, what exactly does the flu do to harm us?
gpt
Viruses hijack cells to create more copies of the virus. Eventually the copies destroy the cell, releasing the copies to invade more cells. The immune reaction, while drastic and somewhat harmful in its own right, is necessary to stop this cell damage.