The virus is composed of a nucleic acid molecule (DNA or RNA) with a protein consisting of non-cell morphology of the campal life of the living body. The general symptoms of viral infection are fever, headache, cough and other symptoms of systemic poisoning and viral host and invasion of tissues and organs leading to inflammatory symptoms caused by local symptoms (diarrhea, rash, liver function damage, etc.). Different symptoms of the different virus, some viruses can also damage the myocardium, causing viral myocarditis. There are two types of viral infections, mostly recessive infections (subclinical infections), and a few are dominant infections. Dominant infection can be divided into acute infection and persistent infection. There are many ways of antiviral infection, such as direct inhibition or killing of viruses, interference with virus adsorption, prevent viruses from penetrating cells, inhibit viral biosynthesis, inhibit viral release or enhance host antivirus capabilities. At present, there are several major types of antiviral drugs: anti-respiratory virus infection drugs, anti-immune virus drugs, anti-hepatitis virus drugs, anti-herpes virus drugs.