The emergence of pandemic influenza A(H1N1) a few months before the 2009 Hajj season was the most recent of these pandemics.9 The lack of an available, effective, and publicly acceptable vaccine in time was just one of

the challenges.10 Restricting age groups at higher risk of complications from attending Hajj activities, as happened for the 2009 Hajj because of the H1N1 influenza threat,10 or even applying PI3K inhibitor a ban on individuals from certain countries during the maximum incubation period as happened with severe acute respiratory syndrome (SARS),11 was considered at length, though not fully implemented, and may be imperative for a future Hajj or other mass gathering events to combat future epidemics. This study was conducted to better document whether the several recommendations that were put into practice before the launch of 2009 Hajj season10 were effective in reducing the spread of pandemic influenza A(H1N1) and other viruses among pilgrims. The study’s primary objective

was to determine whether pilgrim attendance at Hajj venues increased risk of acquiring influenza (or other respiratory viruses). An additional GW-572016 order objective was to assess compliance with influenza immunization and other recommended preventive measures. Our study uses data collected from pilgrims participating in the 2009 (1430H) Hajj. The main religious activities of the 2009 Hajj season started on November 25, 2009 and continued for 5–6 days, according to each pilgrim’s plan. The 2009 Hajj, similar to the Hajj in other years, included Muslims from all over the world, was one of the world’s largest yearly mass gatherings, and was culturally very diverse, including males and females of different ages, races, educational levels, and socioeconomic levels. Two cross-sectional surveys were conducted at the King Abdulaziz International Airport in Jeddah. It is the main airport used by pilgrims and the Hajj terminal is only used by pilgrims. The first survey was conducted during the week before Hajj activities began on November 25, 2009. As the survey was conducted during a declared influenza A(H1N1) pandemic, all pilgrims arriving at the King Khalid international

Hajj terminal were screened by thermal cameras Hydroxychloroquine order and questioned about flu symptoms. This was documented in the incoming survey, and results were included in the final analysis; however, departing pilgrims were not questioned about flu symptoms. The primary sampling units were incoming flights. It proved impractical to select flights by probability sampling; instead, survey teams, after finishing one flight, generally selected the next arriving flight. After deplaning, pilgrims waited in an arrival room (a separate one for each flight) before immigration formalities began, grouped around rows of seats. Interviewers randomly selected a row, a person around the row, and a clockwise or counterclockwise direction, and then interviewed pilgrims successively until the room cleared.