Hundreds of residents line up for H1N1 vaccinations during the launch of the first Public Health H1N1 vaccine clinics in Los Angeles County on October 23, 2009 in the Los Angeles area community of Encino, California.

Published on October 26, 2009

A patient is immunized with the H1N1 Vaccine by a nurse during the launch of the National pandemic (swine flu) influenza vaccination campaign September 30, 2009 in Perth, Australia.

Published on October 1, 2009

A medical technician assistant analyzes a human saliva sample during the analysis for swine flu virus at the Bavarian federal state for health institute on May 4, 2009 in Oberschleissheim, Germany. The World Health Organization WHO has reported on Monday 985 confirmed cases of the virus, known to scientists H1N1 virus, in a total of 20 countries.

Published on June 11, 2009

Karya Lustig sprays a chemical mist into a hood as she fits and trains doctors and nurses how to use the N95 respiratory mask at the La Clinica San Antonio Neighborhood Health Center April 28, 2009 in Oakland, California.

Published on August 18, 2009

Pedestrians wear surgical masks along Constitution Avenue April 25, 2009 in Tijuana, Mexico. Sandy Huffaker/Getty Images.

Published on April 27, 2009

Tourists are a rare sight on the beaches of Cancun, Mexico, since the swine flu outbreak. Hotels, restaurants, bars and other attractions in Cancun are empty as nervous tourists cancelled travel plans. Officials say recovery could be months away for the tourism industry, a vital part of the national economy.

Published on May 14, 2009

A scientist cuts the end of a human saliva sample in a small-diameter glass tube during the analysis for a A(H1N1) virus, the influenza A(H1N1), commonly being referred to as 'swine flu', on August 14, 2009.

Published on August 20, 2009

Commerce Secretary Gary Locke (L), HHS Secretary Kathleen Sebelius (C) and Homeland Security Secretary Janet Napolitano (R) participate in a news conference on the H1N1 influenza, at the department of Commerce August 19, 2009 in Washington, DC.

Published on August 25, 2009

Nurse Melody McKever (L) administers a nasal spray dose of the H1N1/swine flu vaccine to Pediatrics Chairman Dr. Philip Ozuah at Montefiore Medical Center October 6, 2009 in the Bronx borough of New York City.

Published on October 14, 2009

Isiah Harris receives an H1N1 influenza vaccine at Rush University Medical Center October 6, 2009 in Chicago, Illinois.

Published on October 15, 2009

Pedestrians stand in line at the United States-Mexico border while wearing a surgical masks at the Port of Entry on April 27, 2009 in Tijuana, Mexico.

Published on May 7, 2009

Nurse Melody McKever (L) administers a nasal spray dose of the H1N1/swine flu vaccine to Pediatrics Chairman Dr. Philip Ozuah at Montefiore Medical Center October 6, 2009 in the Bronx borough of New York City.

Published on October 14, 2009

Marisa Grunder, 27 of Wilton, Iowa, is given a shot during trials of an H1N1 vaccine at the University of Iowa Health Center on August 11, 2009 in Iowa City, Iowa.

Published on August 18, 2009