Introduction

Viruses are intracellular obligate parasites that require a host cell in order to replicate. They are ubiquitous and have been observed in organisms from the unicellular (bacteria, protozoa) to the multi-cellular (plants, fungi, animals). Viruses are too small to be observed using conventional light microscopy (with a couple of notable exceptions) and as such were only positively identified during the 20th century. Despite their relatively recent discovery, compared to other pathogens studied at the Institute, the field of human virology has rapidly expanded with new viruses being identified every year. Many viruses, particularly those with an RNA genome have the ability to mutate quickly yet retain the ability to replicate. This can result in the development of resistance to both the host immune system and to antiviral drugs. A focus of this group is to identify crucial components of these pathogens which the virus cannot function without and target these for therapeutic interventions. A crucial development in the therapy of HIV was the combination of drugs which targeted different components of the HIV life cycle which severely limited the ability of the virus to adapt to therapy.