for the use of nonpharmaceutical interventions to reduce 2009-H1N1 influenza A transmission; and the global public health responses to the pandemic as it continues to unfold.

This workshop summary was prepared by the rapporteurs for the Forum’s members and includes a collection of individually authored papers and commentary. Sections of the workshop summary not specifically attributed to an individual reflect the views of the rapporteurs and not those of the Forum on Microbial Threats, its sponsors, or the IOM. The contents of the unattributed sections are based on the presentations and discussions at the workshop.

The workshop summary is organized into sections as a topic-by-topic description of the presentations and discussions that took place at the workshop. Its purpose is to present lessons from relevant experience, to delineate a range of pivotal issues and their respective problems, and to offer potential responses as discussed and described by the workshop participants. Manuscripts and reprinted articles, submitted by some but not all of the workshop’s participants, may be found in Appendixes A1 through A14.

Although this workshop summary provides an account of the individual presentations, it also reflects an important aspect of the Forum’s philosophy. The workshop functions as a dialogue among representatives from different sectors of the infectious disease communities and allows them to present their beliefs about which areas may merit further attention. These proceedings summarize only the statements of participants in the workshop and are not intended to be an exhaustive exploration of the subject matter or represent the findings, conclusions, or recommendations of a consensus committee process.

This workshop took place amid broad-based, global efforts to characterize the 2009-H1N1 influenza A virus, determine its evolutionary origins, and evaluate its potential public health and socioeconomic consequences, while monitoring and mitigating the impact of a fast-moving pandemic. The presentations summarized in this report, and the original contributions by the speakers collected in Appendix A, offer a snapshot of these activities taken in the late summer of 2009, as the Northern Hemisphere’s flu season approached and as the United States prepared to undertake a campaign of mass immunization against 2009-H1N1 influenza A.

The influenza viruses are members of the family Orthomyxoviridae and include influenza virus types A, B, and C (see Box WO-1). Influenza is typically