There is no highly effective treatment for<unk>  flu, but oseltamivir (commercially marketed by Roche as Tamiflu), can sometimes inhibit the<unk>  virus from spreading inside the user's body. This drug has become a focus for some governments and organizations trying to prepare for a possible<unk>  pandemic. On April 20, 2006, Roche AG announced that a stockpile of three million treatment courses of Tamiflu are waiting at the disposal of the World Health Organization to be used in case of a flu pandemic; separately Roche donated two million courses to the WHO for use in developing nations that may be affected by such a pandemic but lack the ability to purchase large quantities of the drug. However, WHO expert Hassan al-Bushra has said: :"Even now, we remain unsure about Tamiflu's real effectiveness. As for a vaccine, work cannot start on it until the emergence of a new virus, and we predict it would take six to nine months to develop it. For the moment, we cannot by any means count on a potential vaccine to prevent the spread of a contagious<unk>  virus, whose various precedents in the past 90 years have been highly pathogenic". Animal and lab studies suggest that Relenza (zanamivir), which is in the same class of drugs as Tamiflu, may also be effective against<unk> . In a study performed on mice in 2000, "zanamivir was shown to be efficacious in treating avian<unk>  viruses H9N2, H6N1, and<unk>  transmissible to mammals". In addition, mice studies suggest the combination of zanamivir, celecoxib and mesalazine looks promising producing a 50% survival rate compared to no survival in the placebo arm. While no one knows if zanamivir will be useful or not on a yet to exist pandemic strain of<unk> , it might be useful to stockpile zanamivir as well as oseltamivir in the event of an<unk> <unk>  pandemic. Neither oseltamivir nor zanamivir can be manufactured in quantities that would be meaningful once efficient human transmission starts. In September, 2006, a WHO scientist announced that studies had confirmed cases of<unk>  strains resistant to Tamiflu and Amantadine. Tamiflu-resistant strains have also appeared in the EU, which remain sensitive to Relenza.
Influenza A virus subtype H5N1
Influenza A virus subtype H6N1
Influenza A virus subtype H3N8
Influenza A virus subtype H5N6
Influenza A virus subtype H1N1
Influenza A virus subtype H10N3
SARS-CoV-2 Iota variant
SARS-CoV-2 Alpha variant