On Fri, 13 Apr 2007 17:58:20 +0200, "Acc Con cc." <acccon from gmail.com>
>Could somebody please help me?
>>>>I have read about all the different types of viruses RNA, DNA etc.
>>I have visited many sites, but could not ascertain whether or not all
>viruses like the influenza virus change its structure.
What do you mean "change its structure"?
If you are referring to genetic variability leading to different
viruses with different (detailed) structures, causing problems for the
immune system... Yes, all viruses mutate, RNA viruses do it at a
particularly high rate, HIV is another example, along with flu, where
it gets talked about a lot as a real problem.
As someone has already noted, flu virus has a segmented genome, and
reassortment of the segments is yet one more path to variability.
Segmented genomes are not so common with viruses, though all higher
organisms (including us) have them. And reassortment is only relevant
when two viruses of different types replicate together in the same