For example: Hepatitis virus which is single stranded RNA and when it attacks the host cell, in the body of the host cell, it becomes doule stranded RNA and from that RNA, it forms DNA.
Roughly 2/3rds of viruses have RNA as opposed to DNA. The term "RNA virus" means that ribonucleic acid is the type of nucleic acid that holds the genome.DNA viruses: adeno, hepadna (hep B), herpes...
Instead of using DNA to infect its' host, it uses RNA. One example of a class/family of RNA virus are retrovirus. The RNA is injected into the host cell and the viral RNA undergoes reverse...