Two different teams came to the same answers about the features and patterns of H5N1bird flu virus.
Running tests on cats and parrots and examining the virus from people who got sick from it, researchers realized how the virus worked, why it is difficult to be passed onto humans and its deadly effects once passed to humans.
It was found that H5N1unlike ordinary influenza viruses didn’t attach to cells in the nose, throat and upper airways but to cells deep in the lungs. A person needs to be in constant contact with infected fowl to contract the virus, but once it attaches to the lung cells, the virus manages to damage and destroy cells and air spaces where oxygen is exchanged for carbon dioxide.
The same pattern followed many of the 184 human cases recorded since late 2003 except for the first human case from the year 2003 where the virus infected the cells all the way from the nose to the lungs.
The virus’s outer surface is coated with a protein hemagglutinin that easily attaches to the sugar molecules that lie on the surface of many cells. Ordinary influenza virus attaches through a sugar "linkage" designated alpha 2,6 while the bird flu virus uses another shape, alpha 2,3.
Alpha 2,6 cells were found to predominate in the upper respiratory system, while alpha 2,3 cells were more present in the lung region. When the bird flu virus develops an ability to attaches to the alpha 2,3, it will become easily spread among humans and possibly cause a pandemic.