Avian Flu Jumps to Mammals (Update: continued evolution to human illness)

I can't break down 2 semesters of virology I took in college in a single internet post, but let me help readers get a basic understanding of "the flu."

The flu is NOT a single disease. It is a whole genus of Viruses in the realm Riboviria and are in the family Orthomyxoviridea which is a family of RNA virus that use RNA-dependent RNA polymerase. Inside the genus Alphainfluenzavirus there are different species of influenza, common referred to as Flu A, B, C, and D. For humans, we are primarily concerned with Flu A and Flu B, again these are different Species of flu. Flu B has a couple of different lineages, but does not have any different Serotypes (subspecies)

Flu A mutates significantly more frequently than Flu B and is the one we are concerned about jumping species and causing pandemics and epidemics. Flu A's different Serotypes have nomenclature that identifies specific proteins found on the virus' surface which is how they are categorized. These two groups of proteins are Hemagglutinin and Neuraminidase. For Hemagglutinin there are 18 different subtypes, and Neuraminidase has 11. The nomenclature identifies which proteins are present. Currently we are worried about H5N1, which primarily affects the bird population so it's called a "bird flu." You may remember the swine flu a few years ago that was a H1N1 virus. So since there is H(1-18) and N(1-11) "the flu" is actually 198 different disease causing viruses. That's just Flu A. We have only seen about 120 or so of these combinations in nature so far.

"Bird Flu" refers to a group of Flu A subtypes that we usually only see in birds, but as they mutate that can "jump" across species.

"Bird Flu" is absolutely NOT a HOAX.