1. Attachment and Entry: The virus first attaches to the surface of a host cell, usually a cell in the respiratory tract. It then enters the cell, either by fusing with the cell membrane or by being engulfed by the cell.
2. Uncoating: Once inside the cell, the virus releases its genetic material, which is made up of RNA.
3. Replication: The viral RNA is then transcribed into messenger RNA (mRNA), which is used to produce viral proteins. The viral RNA is also replicated, creating new copies of the viral genome.
4. Assembly: New viral proteins and RNA molecules then assemble into new virus particles.
5. Release: The newly assembled viruses bud off from the host cell, acquiring a lipid envelope as they do so. This allows the viruses to infect other cells and continue the cycle of replication.
Key things to remember:
* No cell division: Unlike bacteria or human cells, viruses don't reproduce by cell division. They rely on the host cell's machinery to create new viral particles.
* Viral RNA: The genetic material of H1N1 is RNA, not DNA like human cells.
* Specific targets: Influenza viruses specifically target cells in the respiratory tract.
The ability of H1N1 to reproduce quickly within the host is why influenza infections can spread so rapidly. However, the immune system can fight off the infection by producing antibodies that target the virus and prevent it from attaching to cells. Vaccines also work by exposing the body to a weakened version of the virus, allowing the immune system to develop immunity without causing illness.
