The 2009 flu pandemic in the United States was a novel strain of the Influenza A/H1N1 virus, commonly referred to as "swine flu", that began in the spring of 2009. The virus had spread to the US from an outbreak in Mexico.[116]
As of mid-March 2010, the U.S. Centers for Disease Control and Prevention (CDC) estimated that about 59 million Americans contracted the H1N1 virus, 265,000 were hospitalized as a result, and 12,000 died.[117] [118]On April 22, the CDC first activated its Emergency Operations Center (EOC). On April 25, the World Health Organization (WHO) declared a public health emergency of international concern.
The disease then spread across the country's population and by the end of May had infected citizens in all 50 states. The pattern continued through June of the same year. The total number of confirmed cases varied from 27,717[121] (Centers for Disease Control and Prevention (CDC) confirmed and probable cases) and 25,453 (total of all state confirmed cases) as of June 26, 2009.
Towards the middle of June 2009, the number of US cases surpassed those of Mexico, which had been the previous leader in diagnosed cases of the disease. Toward the end of June 2009, the number of deaths related to the virus in the US surpassed those of all other countries as well.
On June 25, the CDC released information revealing that there were more than likely over one million (1,000,000) cases of the disease in the US, most of which had not been reported or diagnosed.[122][123]
Deaths relating to this new strain of influenza began appearing in the US in late April, and by early June 15, states had reported fatalities related to or directly occurring from the virus. These deaths totaled at 4,000 as of November 15, 2009. The CDC distributed a vaccine for the novel flu strain.[124] using mechanisms already in place for its Vaccines for Children (VFC) program.[125]
On April 26, 2009, the U.S. Department of Health and Human Services declared Swine Flu a public health emergency. [126] On October 24, 2009, President Barack Obama declared Swine Flu a national emergency in the United States.