Anti Virals interferon, which stimulate cellular defenses against viruses, reducing cell dna synthesis and making cells more resistant to viral genes, enhancing cellular immune responses or suppressing their replication

Anti Virals drugs are useful to reduce morbidity and mortality
during a pandemic. Since effective vaccines are unlikely to be available in the early phase of a pandemic, antiviral drug will be the only virus-specific
intervention available. There are two classes of antiviral drugs specific for
influenza, namely M2 blockers (amantadine and rimantadine) and
neuraminidase inhibitors (oseltamivir and zanamivir).

Studies have demonstrated that some, but not all, strains of H5N1
are resistant to M2 blockers. The susceptibility of pandemic strains should be taken into consideration when choosing antiviral agents. Both oseltamivir and zanamivir are active for the treatment of influenza. Though the latter is not yet approved for influenza prophylaxis in some countries, both oseltamivir and zanamivir are licensed in Hong Kong for treatment and prophylaxis against influenza.