"Over the past 20 years, antiviral therapy has undergone a revolution and is now making a significant impact on the treatment of major virus diseases, for example HIV and viral hepatitis B and C. Targets include viral reverse transcriptases and proteases. The use of interferon to boost host immunity has also proved effective. Our understanding of chemotherapeutic strategies and drug resistance has become considerably more sophisticated since the widespread introduction of routine genome sequencing of virus isolates." . . .