title: The Unrecognized Burden of Influenza in Young Kenyan Children, 2008-2012.
abstract: Influenza-associated disease burden among children in tropical sub-Saharan Africa is not well established, particularly outside of the 2009 pandemic period. We estimated the burden of influenza in children aged 0-4 years through population-based surveillance for influenza-like illness (ILI) and acute lower respiratory tract illness (ALRI). Household members meeting ILI or ALRI case definitions were referred to health facilities for evaluation and collection of nasopharyngeal and oropharyngeal swabs for influenza testing by real-time reverse transcription polymerase chain reaction. Estimates were adjusted for health-seeking behavior and those with ILI and ALRI who were not tested. During 2008-2012, there were 9,652 person-years of surveillance among children aged 0-4 years. The average adjusted rate of influenza-associated hospitalization was 4.3 (95% CI 3.0-6.0) per 1,000 person-years in children aged 0-4 years. Hospitalization rates were highest in the 0-5 month and 6-23 month age groups, at 7.6 (95% CI 3.2-18.2) and 8.4 (95% CI 5.4-13.0) per 1,000 person-years, respectively. The average adjusted rate of influenza-associated medically attended (inpatient or outpatient) ALRI in children aged 0-4 years was 17.4 (95% CI 14.2-19.7) per 1,000 person-years. Few children who had severe laboratory-confirmed influenza were clinically diagnosed with influenza by the treating clinician in the inpatient (0/33, 0%) or outpatient (1/109, 0.9%) settings. Influenza-associated hospitalization rates from 2008-2012 were 5-10 times higher than contemporaneous U.S. estimates. Many children with danger signs were not hospitalized; thus, influenza-associated severe disease rates in Kenyan children are likely higher than hospital-based estimates suggest.
authors.affiliation: Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, United States of America; United States Public Health Service, Rockville, Maryland, United States of America.
authors.forename: Meredith L
authors.initials: ML
authors.lastname: McMorrow
authors.affiliation: Centers for Disease Control and Prevention-Kenya Country Office, Nairobi, Kenya.
authors.forename: Gideon O
authors.initials: GO
authors.lastname: Emukule
authors.affiliation: Centers for Disease Control and Prevention-Kenya Country Office, Nairobi, Kenya.
authors.forename: Henry N
authors.initials: HN
authors.lastname: Njuguna
authors.affiliation: Kenya Medical Research Institute (KEMRI), Nairobi and Kisumu, Kenya.
authors.forename: Godfrey
authors.initials: G
authors.lastname: Bigogo
authors.affiliation: United States Public Health Service, Rockville, Maryland, United States of America; Centers for Disease Control and Prevention-Kenya Country Office, Nairobi, Kenya; Division of Global Health Protection, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Joel M
authors.initials: JM
authors.lastname: Montgomery
authors.affiliation: Kenya Medical Research Institute (KEMRI), Nairobi and Kisumu, Kenya.
authors.forename: Bryan
authors.initials: B
authors.lastname: Nyawanda
authors.affiliation: Kenya Medical Research Institute (KEMRI), Nairobi and Kisumu, Kenya.
authors.forename: Allan
authors.initials: A
authors.lastname: Audi
authors.affiliation: Centers for Disease Control and Prevention-Kenya Country Office, Nairobi, Kenya; Emory Global Health Institute, Emory University, Atlanta, Georgia, United States of America.
authors.forename: Robert F
authors.initials: RF
authors.lastname: Breiman
authors.affiliation: Centers for Disease Control and Prevention-Kenya Country Office, Nairobi, Kenya.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Katz
authors.affiliation: Centers for Disease Control and Prevention-Kenya Country Office, Nairobi, Kenya.
authors.forename: Leonard
authors.initials: L
authors.lastname: Cosmas
authors.affiliation: Centers for Disease Control and Prevention-Kenya Country Office, Nairobi, Kenya.
authors.forename: Lilian W
authors.initials: LW
authors.lastname: Waiboci
authors.affiliation: Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, United States of America; Battelle, Atlanta, Georgia, United States of America.
authors.forename: Jazmin
authors.initials: J
authors.lastname: Duque
authors.affiliation: Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, United States of America.
authors.forename: Marc-Alain
authors.initials: MA
authors.lastname: Widdowson
authors.affiliation: Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, United States of America; United States Public Health Service, Rockville, Maryland, United States of America; Centers for Disease Control and Prevention-Kenya Country Office, Nairobi, Kenya.
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Mott
mesh_terms: D002675:Child, Preschool; D005260:Female; D006760:Hospitalization; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007251:Influenza, Human / Q000453:epidemiology*; D007297:Inpatients; D007630:Kenya / Q000453:epidemiology; D008297:Male; D010045:Outpatients; D058873:Pandemics; D011159:Population Surveillance