Despite major differences in structure to the host, viruses utilize their host cells' enzymes and ribosomes to metabolize and replicate. Therefore, drugs that are effective against viral replication are likely to be toxic to the host as well. Hence, the strategy is to look for process that is unique that happens in virus infected cells but not in uninfected cells. Additionally, finding an enzyme that viruses decoded and that catalyze the process and find ideas for inhibiting replication of the virus.
