What Are the Different Types of Viruses?
Virus-like, also known as infectious RNA, pathogenic RNA, and shell virus, is an infectious particle similar to a virus. A viroid is a type of circular closed single-stranded RNA molecule with a molecular weight of about 105 Da ("eukaryotic virus" is 106 to 108 Da) and contains 246 to 401 nucleotides. Viruses are only naked RNA molecules, rod-shaped structures, no capsid protein and mRNA activity. To distinguish them from viruses, they are named virus-like. Virus-like RNA exists as a highly base-paired rod-like structure in its natural state. Viruses can tolerate ultraviolet rays and various physical and chemical factors acting on proteins, such as proteases, trypsin, urea, etc. are not sensitive and are not damaged by proteases or DNA enzymes, but are extremely sensitive to RNases. 
- Based on whether the virus-like RNA structure contains a conserved region module
- Research on virus-like diseases may contribute to revealing major theoretical issues in life sciences, such as the origin and evolution of life, and the realization of life processes.