title: Seroepidemiology of Chlamydia pneumoniae TWAR infection in Seattle families, 1966-1979.
abstract: Incidence rates of Chlamydia pneumoniae infection and information on reinfection and transmission within families were obtained by serologic study of serum samples from prospective family studies conducted 1966-1979. Specimens (n = 3671) from 343 subjects in 68 families were tested for TWAR antibody using the microimmunofluorescence assay. Acute infection was defined as a fourfold rise in antibody titer between consecutive specimens. Sixty-four episodes of infection were identified in 58 persons; 4 had 2 infections and 1 had 3. From late 1975 until early 1979, when 3 serum specimens were collected yearly, rates of infection by age groups 0-4, 5-9, 10-14, 15-19, and greater than or equal to 20 years were 0, 9.2, 6.2, 2.2, and 1.5/100 person-years, respectively. Reinfections, defined as infections in persons with previous antibody, constituted most acute infections among adults. Acute infections more often affected a single family member than multiple members, but 2 or 3 family members were infected during the same period 12 times.
authors.affiliation: Department of Epidemiology, University of Washington, Seattle 98195.
authors.forename: M B
authors.initials: MB
authors.lastname: Aldous
authors.forename: J T
authors.initials: JT
authors.lastname: Grayston
authors.forename: S P
authors.initials: SP
authors.lastname: Wang
authors.forename: H M
authors.initials: HM
authors.lastname: Foy
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood; D002648:Child; D002675:Child, Preschool; D002690:Chlamydia Infections / Q000097:blood / Q000453:epidemiology* / Q000635:transmission; D016993:Chlamydophila pneumoniae; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016036:Seroepidemiologic Studies; D014861:Washington / Q000453:epidemiology
chemical_list: D000907:Antibodies, Bacterial