The 2009 Influenza A(H1N1) 'Swine Flu' Outbreak: An Overview

On April 29, 2009, in response to the global spread of a new strain of influenza, the World Health Organization WHO raised its influenza flu pandemic alert level to Phase 5, one level below declaring that a global influenza pandemic was underway. Officials now believe the outbreak began in Mexico in March 2009, or earlier. The novel flu virus was first identified in California in late April 2009. Health officials quickly linked the new flu strain to many of the illnesses in Mexico. Since then, growing numbers of cases have been reported around the world. As of May 20, 2009, more than 10,000 cases had been reported in 41 countries in North and South America, Europe, Asia, and Oceania. Most of the reported cases are in Mexico, the United States, and Canada. Health officials note that reported cases likely represent only a fraction of actual infections. Federal agencies have adopted a pandemic response posture under the overall coordination of the Secretary of Homeland Security. Among other things, officials have released antiviral drugs from the national stockpile, and efforts to develop a vaccine are underway. The Obama Administration has requested 1.5 billion in emergency supplemental appropriations to address the threat, and additional amounts for FY2010. This report first provides a synopsis of key events, actions taken, and authorities invoked by WHO, the U.S. federal government, and state and local governments. It then discusses the WHO process to determine the phase of a threatened or emerging flu pandemic, and selected actions taken by the Departments of Homeland Security and Health and Human Services, and by state and local authorities. Next, it lists congressional hearings held to date and provides information about appropriations and funding for pandemic flu activities. Finally, it summarizes U.S. government pandemic flu planning documents and lists sources for additional information. This report will be continually updated.