How does the flu reproduce?

Answer 1

The influenza viruses, like Swine Flu (H1N1/09), reproduce in a method called the lytic cycle.

As a quick and over-simplified explanation of the lytic cycle: the virus attaches to your cell (flu viruses attach to the cells of mucous tissue, mostly first in the nose, mouth and eyes), inserts its DNA/RNA into the cell and that instructs the cell to stop what it was doing as its normal function for the body and start making replications of the virus instead. In that way, the virus, a non-living organism, hijacks our bodies to supply the raw materials and do the work required to reproduce itself. Once that one cell makes a full batch of virus particles, the cell splits open and the "newbie" virus particles go attach to other cells and repeat the cycle entering cell after cell after cell. The hijacking and death of the split open cells help trigger our bodies to begin the attack on the virus. It is then that we will feel the symptoms of both the loss of the cells from their regular duties, and the immune response that includes the fever, excess mucus production, etc.

See the related questions below for more detailed information about the lytic cycle.

Answer 2

Through the viral process called the Lytic Cycle. Read more about the lytic cycle in the related questions below.

Answer 3

Using the processes of the lytic cycle. See related questions.