title: Serological evidence of the three chlamydial species in an aboriginal community in the Northern Territory.
abstract: OBJECTIVE
  To determine the pattern of seropositivity to the three species of Chlamydia in women and children from a single community.
  
  
  METHODS
  Testing of blood samples obtained during a prospective study of mothers and infants. For each individual, the sample giving the highest titre of antichlamydial antibody was included in the analysis.
  
  
  METHODS
  The only health centre for a small rural community in the Top End of the Northern Territory. This served all 1200 or so residents, almost 95% of whom were Aboriginal.
  
  
  METHODS
  Sixty-one pregnant Aboriginal women at routine antenatal clinic visits, and 114 of their children aged between one and six years at the time of sampling.
  
  
  METHODS
  Specific IgG or IgM antibody to any of the three species of Chlamydia at titres > or = 32, as determined by micro-immunofluorescence.
  
  
  RESULTS
  IgG antibody to one or more chlamydial species was found in 83.6% of mothers and 42.1% of their children. IgM antibody was found in five mothers and four children, in each case against only one chlamydial species. IgG antibody to C. trachomatis was found in 55.7% of mothers and 28.9% of children, to C. pneumoniae in 59.0% of mothers and 19.3% of children, and to C. psittaci in 29.5% of mothers and 17.5% of children. Log linear modelling gave positive correlations between seropositivity for C. trachomatis and C. pneumoniae (chi 2 = 9, P < 0.01), and for C. trachomatis and C. psittaci (chi 2 = 15, P < 0.001). Cross-reactivity was more evident in children than in mothers.
  
  
  CONCLUSIONS
  This is the first Australian report providing serological evidence of exposure to the three chlamydial species in one community. The seropositivity patterns suggest complex interactions when all species are present.
authors: Menzies School of Health Research, Casuarina, NT.
authors: L V
authors: LV
authors: Asche
authors: S I
authors: SI
authors: Hutton
authors: F P
authors: FP
authors: Douglas
mesh_terms: D000907:Antibodies, Bacterial / Q000032:analysis; D002648:Child; D002675:Child, Preschool; D002689:Chlamydia / Q000276:immunology / Q000302:isolation & purification*; D002690:Chlamydia Infections / Q000453:epidemiology; D002692:Chlamydia trachomatis / Q000302:isolation & purification; D016993:Chlamydophila pneumoniae / Q000302:isolation & purification; D002691:Chlamydophila psittaci / Q000302:isolation & purification; D003429:Cross Reactions; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007223:Infant; D007231:Infant, Newborn; D015876:Northern Territory / Q000453:epidemiology; D011247:Pregnancy; D011446:Prospective Studies; D016036:Seroepidemiologic Studies; D000095283:Australian Aboriginal and Torres Strait Islander Peoples
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G