In my experience, the term "adaptation" has been used extensively by con-men who use the word to describe evolution without actually using the word "evolution." Those con-men also have very limited understanding of evolution--the "adaptation" process they describe in order to avoid using the word "evolution" actually proceeds orders of magnitude faster than real evolution, and would result in greater change far faster than we actually observe. There actually is no "adaptation"--what happens is that viruses reproduce so rapidly that a person can be infected with millions or billions of virus particles at a time. And since each new virus is genetically different (genetic mutation happens during reproduction of any organism), some of those viruses happen to have mutations that make them better suited for survival.
The changes in the flu virus are in the genetic material, which, by definition, means they are evolutionary changes. That is because any change in an organism is coded in the genetic material, and the genetic material changes randomly, spontaneously, and constantly. For the most part, those changes in the flu virus enable it to bypass the immune system. That is why you can get the flu over and over, and why the flu vaccine has to be changed every year.
That is not evolution and no scientist has been able to change the DNA of one virus to another or it would be cured completely. You are interchanging words from adaptation to evolution which is completely different.
Not all viruses use DNA, some use RNA instead. Besides that, scientists change the DNA and RNA of viruses all the time, and have created many viruses that do not exist in nature. Is that evolution? No, but it is using the tools and principles of evolution to come up with things not found in nature. BTW, this kind of research is strictly regulated, and scientists are careful to maintain positive control over new organisms.
Why as a scientist would you spend your time defending it rather than poking holes in it to see if it can withstand scrutiny? Because it is a political tenant just like Global Warming. Do you really believe man came from an amoeba?
By its nature, science is a process of poking holes in assumptions and trying to test them. We spend our lives not trying to positively prove things, but trying to disprove them. Not only that, but we criticize and poke holes in other scientists' work. If you are a scientist and you want to publish your research results, one of the first things you do is send your manuscript to other scientists to be criticized. If the manuscript holds up to their scrutiny, you send it to a scientific journal, which sends it to other scientists, experts in your field, who read it and do their best to poke holes in it. Usually, you have to fix things about the manuscript before you can publish it, but once it has survived all the criticism and attempts to poke holes, it can be published. This is the peer-review process.
Part of the process of educating young scientists is teaching them to be critical and to be ruthless about questioning assumptions.
As I pointed out before, the concept of "global warming" is pretty much in its own category. You have to understand that politicians have agendas, and they distribute funding for research. And research progress is reported to Congress, very few of whom are scientists. As an example, someone who is studying the spread of Zika virus northwards into the US is undoubtedly looking at the issue very scientifically, examining where susceptible mosquito populations are, how efficiently the virus is transmitted human to mosquito back to human, etc. Invasion of species into areas where they have never been before is nothing new; it has been going on since there has been life on earth. Perhaps, for whatever reason, that scientist studying Zika virus does not think it is getting enough attention and that more people need to be researching it. Well, that scientist is competing with thousands of other scientists, each clamoring that their avenue of research has major public health implications. How does that Zika virus researcher make his/her voice a little louder than the other researchers? By tying it to global warming, because every scientist is aware that our scientifically illiterate Congress will notice the words "global warming" before they perceive the health threat.
I do not "believe" that humans evolved from earlier primates, which evolved from earlier organisms, and so on back a few billion years. That is what the evidence shows; it takes no particular effort to "believe" it. Do you really believe that the visible universe is only 6,000 light-years in radius, and that God is deceiving us by making it look like some stars are millions and billions of light-years away? Or that He is deceiving us by planting evidence of geological and biological evolution in the earth around us and even in the genetic material of every living organism?
You are talking about your specialty, but your are not talking evolution you are talking adaptation and mutations. You are simply mutating something into a specialized virus but it is not the same as changing into a whole new species.
I doubt you are purposely confusing the issue, but you are not proving evolution exists. There are plenty of good scientists that understand exactly what you are talking about and dismissing it as true transformation of species.
http://www.evolutionnews.org/2013/04/genetics_is_too071621.html