[Virology] Do all viruses change there structure?

[Acc Con cc.]

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.

 

The more I read the more interesting the viral world becomes, but I am
getting tired now so I would greatly appreciate if somebody could tell me
yes or no.

 

Rikus

Gauteng

South Africa