title: Effects of age, breast feeding, and household structure on Haemophilus influenzae type b disease risk and antibody acquisition in Alaskan Eskimos.
abstract: Invasive Haemophilus influenzae type b (Hib) disease occurs with unusually high incidence in Alaskan Eskimos. In 1983, the authors evaluated the unique susceptibility of the Yupik-speaking Eskimo population in southwest Alaska. A matched case-control design was used to assess the influence of age, breast feeding, and household composition on disease risk, with a historical cohort design to evaluate their effects on acquisition of Hib anticapsular antibody. The authors studied 103 cases with known invasive Hib disease that occurred at a mean age of 8.7 +/- 8.6 months; healthy controls were matched for age and village of residence. Living in extended families at the time of disease onset was significantly associated with Hib disease (p less than 0.04; odds ratio = 1.8; 95% confidence interval 0.87-3.25). The authors found that breast feeding was significantly less common among cases than controls (p less than 0.03; odds ratio = 0.53; 95% confidence interval 0.27-0.98). Although there was a positive correlation between age and acquired level of total anticapsular antibody (r = 0.59; p less than 0.0001), previous exposure to invasive Hib disease did not influence these levels. Household crowding and breast feeding also did not appear to affect Hib antibody acquisition.
authors.affiliation: Department of Epidemiology, Johns Hopkins University School of Hygiene and Public Health, Baltimore, MD.
authors.forename: G M
authors.initials: GM
authors.lastname: Petersen
authors.forename: D R
authors.initials: DR
authors.lastname: Silimperi
authors.forename: C Y
authors.initials: CY
authors.lastname: Chiu
authors.forename: J I
authors.initials: JI
authors.lastname: Ward
mesh_terms: D000367:Age Factors; D000413:Alaska / Q000453:epidemiology; D000907:Antibodies, Bacterial / Q000032:analysis*; D001942:Breast Feeding; D016022:Case-Control Studies; D015331:Cohort Studies; D005191:Family Characteristics; D005260:Female; D006192:Haemophilus Infections / Q000097:blood / Q000453:epidemiology*; D006193:Haemophilus influenzae; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D004930:Inuit; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D000907:Antibodies, Bacterial