Table 4.

Summary of influenza disease burden estimation studies conducted in the WHO Eastern Mediterranean Region.

Country	Study title	Indicator	Study method	Study population	Study period	Findings	Seasonality	Status
Egypt (8)	Incidence of influenza virus-associated severe acute respiratory infection in Damanhour district, Egypt, 2013	IR	Healthcare use survey to identify the catchment population	685,641 (Damanhur district)	January-December 2013	•Overall IR: 44/100,000 person-years • Age group (years): - 0 to <2: 72/100,000 person year - 2 to 4: 166/100,000 person year - 5 to <15: 26/100,000 person year - 15 to <50: 30/100,000 person year - 50 to <65: 89/100,000 person year - ≥65: 46/100,000 person year •Pregnant women: 17.3/100,000 person year	•Most SARI cases were in autumn and early winter when the influenza virus positivity rate in SARI patients ranged from 20 to 38%. •Transmission of influenza viruses was seen throughout the year	Published
Iran (9)	Estimation of influenza and SARI incidence (burden) in three provinces of the Iran, 2012 and 2013	IR	Population census	3,279,823 (Western Azerbaijan, Alborz and Hamedan)	2012 to 2013	• The mean annual incidence for all age groups for influenza-associated illness : - Alborz province: 15.0 and 147.8/100,000 population respectively - Hamedan province: 9.3 and 62.7/100,000 population respectively - West Azerbaijan: 36.7 and 299.8/100,000 population respectively.	•The seasonal peaks for SARI cases occurred in May-June.	Published
Jordan (6)	Descriptive epidemiology of SARI cases and estimation the proportion of SARI cases attributable to influenza	Proportion of positive influenza cases	Total number of SARI cases admitted	2891 (admitted patients in the four sentinel sites)	January 2008 to February 2014	•Proportion SARI cases positive for influenza (9%) •Proportion influenza positive cases amongst SARI in under 5 years (57%)	•The influenza-positive cases peaked during November-January (14-42%)	Published
Lebanon (7)	Seasonal influenza-associated SARI in a southern governmental sentinel site in Lebanon	Proportion of SARI/influenza cases	Total number of all-cause admissions	468,464 (patients admitted in two sentinel sites)	1 September 2015 to 31 August 2016	• Overall proportion SARI to all hospital admissions: - Southern sentinel sites: 0.9% - Beirut suburb: 0.2%	•The highest wave of SARI reports for both sentinel sites was between weeks 1 and 10 of 2016	Published
Morocco	Estimating influenza disease burden in a sentinel site in Morocco	IR	Health admission survey	15,985 (Meknes-Tafilalet)	September 2008-August 2012	•Incidence of influenza-associated SARI was 72.1 and 30.1/100,000 during seasons 2009-2010 and 2011- 2012 respectively •In-hospital case fatality ratio was 6.6% for the age group 2-5 years and 12.5% for the age group 15-50 years •Proportional contribution of influenza to annual outpatient ILI was 20% in December 2009 and 12% in January 2010	The cyclic influenza epidemic generally begins in November and starts to go down in March	In process
Oman (4)	Estimating the burden of influenza-associated hospitalization and deaths in Oman (2012-2015)	Proportion of influenza-associated hospitalizations and in-hospital deaths	Discharge records based on ICD-10 codes (J 09- 18)	4,588,683 (total Oman population)	2012-2015	•Incidence of influenza-associated hospitalization in the study period was 20.6 (95% CI: 19.9-21.3) per 100,000 population •People aged ≥65 years had the highest annual incidence of influenza-associated in-hospital death in all the study years, ranging between 11.3 in 2015 and 39.5 per 100,000 population in 2014.	•Influenza peaks differed from season to season. In 2013-14 and 2014-15 seasons the peak was in spring (March-April) and in 2012-13 and 2015-16 seasons it was in December	Published
Tunisia (10)	Estimating the seasonal influenza burden in Tunisia [8]	IR	Population census	11,151,874 (population covered by ILI sites)	3 seasons (2012-2013, 2013-2014, 2014-2015)	•IR of influenza-associated ILI/100,000 were 18,735 in 2012/13 season, 5536 in 2013/14 and 12,602 in 2014/15. •Estimated proportion of influenza-associated ILI of the total outpatient visits were 3.16%, 0.86% and 1.98% in the 3 seasons respectively.	•Influenza season starts late December and peaks in March	Published
Saudi Arabia (11)	Influenza is more common than Middle East Respiratory Syndrome Coronavirus (MERS-CoV) among hospitalized adult Saudi patients	Proportion of influenza positive cases amongst community acquired pneumonia cases	Analysis of surveillance data on community acquired pneumonia in a general hospital over a four-year period	2657 patients records	2012-2016	•A total of 1644 patients were tested for both MERS-CoV and influenza. None of the patients tested positive for MERS-CoV and 271 (16.4%) were positive for influenza. The detected influenza viruses were Influenza A (107, 6.5%), pandemic 2009 H1N1 (n = 120, 7.3%), and Influenza B (n = 44, 2.7%).	•Influenza cases peaked from October to December •Influenza A other than A(H1N1)pdm09 peaked in August and between October to December.	Published

IR: incidence rate, SARI: severe acute respiratory illness, ILI: influenza-like illness, CI: confidence interval.