title: Risk factors associated with typhoid fever in children aged 2-16 years in Karachi, Pakistan.
abstract: We analysed the data from the control group in a typhoid vaccine trial in Karachi to assess the differences in individual-, household- and cluster-level characteristics for developing typhoid fever. The annual incidence of typhoid in children aged 2-16 years in the control arm of the vaccine trial was 151/100 000 population. After adjustment, the risk of typhoid was lower with increasing age [risk ratio (RR) 0·89, 95% confidence interval (CI) 0·83-0·95], was higher with an increase in population density (RR 1·13, 95% CI 1·05-1·21) and was lower in the households using a safe drinking-water source (RR 0·63, 95% CI 0·41-0·99). Typhoid fever affects younger children living in areas of high population density and lack of access to safe water in Pakistan. A combination of environmental and biological interventions is required to prevent the continued epidemiological and economic impact of typhoid fever in high-risk areas of Pakistan.
authors.affiliation: International Vaccine Institute, Seoul, South Korea.
authors.forename: M I
authors.initials: MI
authors.lastname: Khan
authors.forename: R L
authors.initials: RL
authors.lastname: Ochiai
authors.forename: S B
authors.initials: SB
authors.lastname: Soofi
authors.forename: L
authors.initials: L
authors.lastname: Von-Seidlein
authors.forename: M J
authors.initials: MJ
authors.lastname: Khan
authors.forename: S M
authors.initials: SM
authors.lastname: Sahito
authors.forename: M A
authors.initials: MA
authors.lastname: Habib
authors.forename: M K
authors.initials: MK
authors.lastname: Puri
authors.forename: J K
authors.initials: JK
authors.lastname: Park
authors.forename: Y A
authors.initials: YA
authors.lastname: You
authors.forename: M
authors.initials: M
authors.lastname: Ali
authors.forename: S Q
authors.initials: SQ
authors.lastname: Nizami
authors.forename: C J
authors.initials: CJ
authors.lastname: Acosta
authors.forename: R
authors.initials: R
authors.lastname: Bradley-Sack
authors.forename: J D
authors.initials: JD
authors.lastname: Clemens
authors.forename: Z A
authors.initials: ZA
authors.lastname: Bhutta
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D060766:Drinking Water / Q000821:virology; D005191:Family Characteristics; D005260:Female; D006801:Humans; D008297:Male; D010154:Pakistan / Q000453:epidemiology; D011156:Population Density; D012307:Risk Factors; D012485:Salmonella typhi; D012959:Socioeconomic Factors; D014435:Typhoid Fever / Q000453:epidemiology / Q000209:etiology*; D014436:Typhoid-Paratyphoid Vaccines / Q000627:therapeutic use
chemical_list: D060766:Drinking Water; D014436:Typhoid-Paratyphoid Vaccines