Two classes of antiviral medication are available for the treatment of seasonal human infl uenza: neuraminidase inhibitors (oseltamivir and zanamivir) and adamantanes (rimantadine and amantadine). During the 2008-2009 infl uenza season, almost all circulating human infl uenza A (H1N1) viruses in the United States were resistant to oseltamivir [14] . However, genetic and phenotypic analyses indicate that novel H1N1 2009 is susceptible to oseltamivir and zanamivir but resistant to the adamantanes [15] . The Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA has recommended that given the severity of illness observed among some patients with novel H1N1 2009 infection, therapy with neuraminidase inhibitors should be prioritized for hospitalized patients with suspected or confi rmed novel H1N1 2009 infection and for patients who are at high risk for complications from seasonal infl uenza.