How Does the Flu Virus Reproduce?

Influenza is a cunning virus that uses the cells in your respiratory system to reproduce. By using the materials within the cells of your body to make copies of itself, the flu virus can reproduce quickly and efficiently. After copies of the virus burst out of the cell they first infect, the virus can spread quickly through your respiratory system. Soon after initial infection, influenza causes symptoms that allow the virus to exit the body and infect another person.

Entering the Cell

Viruses reproduce by using cells in the body as nurseries for their offspring. For the flu virus to reproduce, it first has to bind to the walls of cells in the respiratory tract. When it binds to a cell in the body, the flu virus is taken into the center of the cell and coated with the cell's own membrane. This coating makes the environment around the virus more acidic, causing it to release its genetic material.

Reproduction of Genetic Materials

Once inside the cell, the virus' genetic material enters the nucleus of the cell. Here, the cell's genetic material is chopped up and rearranged into versions of the flu virus. Because the virus reproduces quickly and does not have the capacity to ensure that each copy of the virus is identical, many of these offspring are mutants of the first virus. This is one reason why influenza mutates so quickly. The reproduction of the flu virus is devastating to the cell, and each cell that incubates the flu virus is destroyed after the new viruses burst out of the cell.

Spreading of Cells

After the cell bursts with new influenza viruses, the flu can infect all the neighboring cells. After one cell has been infected, thousands of flu viruses can be produced in five hours. Because all the cells of the respiratory tract contain the proteins and acids that the virus needs to reproduce, the whole human respiratory system is easily infected.

Spreading Outside of the Body

When the cells that harbor the flu die, inflammation of the area results. This causes the body to react by coughing. The flu can latch onto the droplets that are expelled from the body in a coughing fit. Millions of viruses can exit with each droplet, and thousands of droplets are expelled. When someone inhales these droplets or transfers them from a surface to their mouth, eyes or nose, the entire reproduction process begins again.

References

• Lauren Sompayrac; How Pathogenic Viruses Work; 2002

Resources

• CDC Influenza Page