Permanent Resident Virus in Human Beings Viral Microecology of Human Being| Biomed Grid

For analysis of the origin of life, viruses are compatible with cells. The formation, survival, and development of virus depend absolutely on cells. The existence of viruses must have their longterm host for survival, spreading and extending. Like other species in nature, human beings also coexist with a group of human-hosted viruses, which are called permanent resident viruses in human beings. The immune system of species has the anti-microbial invasion function. The virus has a special coexistence mechanism with its long-term host, who has a perfect immune system. Since the immune system has no capacity for entering into cells to recognize and remove viral nucleic acids, the invading viruses can reside in cells for a long time as a recessive existence under the dynamic balance between residual viral replication and immune clearance pressure. In this normal state, the virus and its long-term host are “stakeholders” living harmoniously. Consequently, the normal state of all natural viruses after the occurrence of the immune system of the species, constitutes the viral microecology of the host (excluded viruses parasitic air cavities in microorganisms). Normal state viruses can undergo antigenic mutation to break through immune pressure and become abnormal, then viruses can proliferate again and spread to cause infection in host population. The abnormal state would return into normal state after a new group immune protection to be established again. The primary infection of the normal state virus and the re-infection of the abnormal state virus can cause disease due to the immune toxicity caused by the immune response. The identification of permanent resident viruses in human beings has important significance for studying the epidemiology, pathogenesis, clinical manifestations and outcomes of human viral diseases and epidemics, as well as disease prevention and treatment. Vaccine can successfully prevent the diseases caused by initial infection of normal state viruses. However, for the re-infection of abnormal state viruses, it is difficult to evaluate the preventive effect of vaccines because of the matching problem between previous vaccines and new antigens of virus in abnormal state. The Origin and Evolution of Perma