title: Clustering of seropositivities for sexually transmitted infections.
abstract: BACKGROUND
  Serology for different sexually transmitted infections (STIs) is useful for epidemiologic studies on the spread of STIs in different populations. Studying whether seropositivities for different STIs cluster could be useful, both for development of improved serologic markers of sexual behavior in populations and for understanding how STIs may differ in terms of the dynamics of their spread.
  
  
  OBJECTIVE
  To evaluate the degree of clustering of different STIs in relation to sexual history.
  
  
  METHODS
  An age- and sexual history-stratified subsample of 275 women from a survey of healthy Swedish women seeking contraceptive advice was tested for human papillomavirus (HPV) types 6, 11, 16, 18, and 33; Chlamydia trachomatis; herpes simplex virus 2 (HSV-2); and human herpesvirus 8.
  
  
  RESULTS
  Significant clustering was observed only for HPV types 6 and 11; for HPV types 16, 18, and 33; and for C trachomatis and HSV-2. The serologic marker that correlated best with lifetime number of sex partners was HPV type 16 (odds ratio [OR], 10.2; 95% CI, 3.8-27.6). The combined serologic marker that correlated most highly with sexual history was joint positivity for HPV types 16 and 33 (OR, 25.5; 95% CI, 5.4-120.4).
  
  
  CONCLUSIONS
  The degree of clustering between different STIs varies from nonexistent to strong, implying that different STIs commonly have very different transmission dynamics. Certain combinations of STI serologic tests may be useful in epidemiologic studies for predicting sexual behavior in groups.
authors.affiliation: Microbiology and Tumor Biology Center, Karolinska Institute, Stockholm, Sweden.
authors.forename: Ilvars
authors.initials: I
authors.lastname: Silins
authors.forename: Rosa Maria
authors.initials: RM
authors.lastname: Tedeschi
authors.forename: Ingegerd
authors.initials: I
authors.lastname: Kallings
authors.forename: Joakim
authors.initials: J
authors.lastname: Dillner
mesh_terms: D000328:Adult; D000554:Ambulatory Care Facilities; D000907:Antibodies, Bacterial / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D002690:Chlamydia Infections / Q000453:epidemiology / Q000635:transmission; D002692:Chlamydia trachomatis / Q000302:isolation & purification; D018562:Disease Transmission, Infectious / Q000706:statistics & numerical data*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006558:Herpes Genitalis / Q000453:epidemiology / Q000635:transmission; D018258:Herpesvirus 2, Human / Q000302:isolation & purification; D019288:Herpesvirus 8, Human / Q000302:isolation & purification; D006801:Humans; D016017:Odds Ratio; D027383:Papillomaviridae / Q000145:classification / Q000302:isolation & purification; D030361:Papillomavirus Infections / Q000453:epidemiology / Q000635:transmission; D016036:Seroepidemiologic Studies; D012725:Sexual Behavior; D012747:Sexual Partners; D012749:Sexually Transmitted Diseases / Q000453:epidemiology* / Q000635:transmission*; D011795:Surveys and Questionnaires; D013548:Sweden / Q000453:epidemiology; D014412:Tumor Virus Infections / Q000453:epidemiology / Q000635:transmission
chemical_list: D000907:Antibodies, Bacterial; D000914:Antibodies, Viral