Table 2. Average annual incidence rates of medically-attended influenza A and/or B (hospitalized and outpatient) per 1,000 persons or person-years in Kenya.

Author(s)	Syndrome type	Adjustment used	Study site	Age group	Incidence a Range b
Katz et al. (2012)[11]	In- and outpatient ALRI	Adjusted for those with ALRI who were not tested for influenza	Kibera and Lwak	< 1 yr	32.8–42.1
				<5 yrs	22.0–40.5
				≥5 yrs	12.0–15.8
				All ages	13.7–23.0
Feikin et al. (2013)[14]	In- and outpatient SARI	Adjusted for healthcare seeking by extrapolating from those with ARI ǂ at household visit who sought care at a clinic besides the study clinic and for the pathogen-attributable fraction (PAF ¥ )	Lwak, Western Kenya	<5 yrs	58.0
Breiman et al. (2015)[20]	Outpatient SARI	Adjusted for healthcare seeking for SARI at the study clinic and for the pathogen-attributable fraction (PAF ¥ ).	Kibera	<5 yrs	13.0
Feikin et al. (2012)[13]	In- and outpatient ARI	Adjusted for healthcare seeking by extrapolating from those with ARI ǂ at household visit who sought care at a clinic besides the study clinic and for the pathogen-attributable fraction (PAF ¥ )	Lwak, Western Kenya	≥5 yrs	26.0
Emukule et al. (2014)[18]	Outpatient ILI	Adjusted for those with ILI who were not tested for influenza	Ting'wang'i, Western Kenya	<6 mos	16.2
				<5 yrs	21.8
				≥5 yrs	4.3
				All ages	7.2
All studies	All syndromes	With any adjustment	All study sites	<6 mos	16.2
				< 1 yr	32.8–42.1
				<5 yrs	21.8–58.0
				≥5 yrs	4.3–26.0
				All ages	7.2–23.0

Abbreviations

SARI = Severe acute respiratory illness

ALRI = Acute lower respiratory illness

ILI = influenza-like illness

ARI = Acute respiratory illness

^aIncidence reported per 1,000 persons or person-years

^bRange is the minimum-maximum in cases where two or more studies were involved

^ǂARI in home was defined as cough, difficulty breathing or chest pain and reported fever

^¥Adjusted rates downward for asymptomatic detection of influenza in controls.