Key Points, Part I:
• The 2009 influenza pandemic spread throughout the world at an unprecedented rate. However, global preparedness was also unprecedented in scale compared to previous pandemics.
• Systematic surveillance capacity remains disparate among countries. More than 100 countries have very limited or no influenza surveillance capacity. The heterogeneity of established systems and the lack of standardized indicators made global monitoring difficult.
• Current assessment methodologies have shown to be inadequate for describing the severity of the 2009 pandemic. The Centers for Disease Control and Prevention (CDC) is in the process of developing a new framework that will allow assessment of the pandemic impact based on categories of transmission and clinical severity, instead of case fatality alone. It will also include a “translation-to-action” step, whereby scientific findings can be translated into context-appropriate recommendations.
• Given the role of pigs and domestic and wild birds in the genesis of novel influenza A strains, influenza surveillance in these key animal populations should be enhanced.
• Non-pharmaceutical interventions are an integral part of the public health mitigation strategy to control the spread of influenza during an outbreak. However, the effectiveness of an individual intervention on its own is difficult to assess.
• Although border screening may not be effective in containing pH1N1, implementation of this mitigation measure in some countries might have delayed local pH1N1 transmission by an additional seven to 12 days compared to countries that did not implement border screening.
• Because school closures can have substantial economic and social costs, whether to close schools or not is a highly contextualized decision.
• Hand hygiene and the use of face masks are the chief protective measures at the individual level. However, evidence supporting the use of such measures in the community setting is, by and large, conflicting or lacking.