Infection

Virus infection of higher organisms is the cumulative result of all the processes of replication and gene expression described in the previous chapters. Together, these determine the overall course of each infection. Infections range in complexity and duration from a very brief, superficial interaction between the virus and its host to infections that may span the entire life of the host organism, from before birth to its eventual death. A common misconception is that virus infection inevitably results in disease. In reality, the reverse is true—only a small minority of virus infections gives rise to any disease symptoms. This chapter provides an overview of the numerous patterns of virus infection and forms an introduction to the discussion of virus pathogenesis in Chapter 7. Unlike previous and subsequent chapters, this chapter deals primarily with the interaction of viruses with intact organisms rather than with the molecular biologist’s usual concern about the interaction between a virus and the cell.