The genetic material of viruses is DNA or RNA. viruses generally contain only one type of genetic material, DNA or RNA, with a protein forming the outer shell. Viruses are very tiny in size, have life characteristics such as genetic and replication characteristics, are highly parasitic, and are completely dependent on the energy and metabolic system of the host cell to obtain the substances and energy required for life activities. In addition, prions, virus-like microorganisms, which may be composed of only proteins or only RNA, can be broadly considered as viruses, and the genetic material of these viruses is their constituents, which means that proteins can also be used as the genetic material of viruses, but the replication mechanism of viruses with proteins as the genetic material is not very clear. Most of the DNA viruses are double-stranded or single-stranded and cannot reproduce alone, but must use the raw materials and energy system of the host cell to synthesize DNA and protein needed for their own reproduction and reassemble into new DNA viruses in the host cell. Most RNA viruses are single-stranded and enter the host cell first, then reproduce directly through RNA replication and transcription, or use the reverse transcriptase they carry to reverse transcribe into DNA and integrate with the host cell’s DNA, then use the host cell DNA replication and transcription process to synthesize the material needed for their own reproduction and reproduction. Virus, mumps virus, rubella virus, hepatitis C virus, hepatitis E virus, etc. are all RNA viruses. Human DNA or RNA viral infections are very common, and the common ways of virus transmission are respiratory transmission, gastrointestinal transmission, and body fluid transmission. Whether it is DNA virus infection or RNA virus infection, there is usually a lack of effective therapeutic drugs, mainly symptomatic supportive treatment, but can also be used under the guidance of doctors to use amantadine, acyclovir and other drugs for antiviral treatment. Most viral diseases can be cured with treatment, while a few severe infections can cause death.