Viral Infection and Disease Classification of Viruses Antiviral Drugs

Viruses are obligate intracellular parasites that use many of the host cell’s biochemical mechanisms and products to sustain their viability. A mature virus (virion) can exist outside a host cell and still retain its infective properties. However, to reproduce, the virus must enter the host cell, take over the host cell’s mechanisms for nucleic acid and protein synthesis, and direct the host cell to make new viral particles.