The 2009 flu pandemic was a global outbreak of a new strain of influenza A virus subtype H1N1, first identified in April 2009, termed Pandemic H1N1/09 virus by the World Health Organization (WHO)[4] and colloquially called swine flu.

[6][7] The overwhelming majority of patients experience mild symptoms",[6] but some persons are in higher risk groups, such as those with asthma, diabetes,[8][9] obesity, heart disease, or who are pregnant or have a weakened immune system.

[10] In the rare severe cases, around 3–5 days after symptoms manifest, the person's condition declines quickly, often to the point respiratory failure.

A U.S. citizen, flying from the United States via Amsterdam was found to have the swine flu after arriving at Istanbul's Atatürk International Airport.

[14] After a slow start, the virus spread rapidly in Turkey and the number of cases reached 12,316.