title: HIV prevalence by race co-varies closely with concurrency and number of sex partners in South Africa.
abstract: BACKGROUND
  HIV prevalence differs by more than an order of magnitude between South Africa's racial groups. Comparing the sexual behaviors and other risk factors for HIV transmission between the different races may shed light on the determinants of South Africa's generalized HIV epidemic.
  
  
  METHODS
  Five nationally representative and one city-representative population-based surveys of sexual behavior were used to assess the extent to which various risk factors co-varied with HIV prevalence by race in South Africa.
  
  
  RESULTS
  In 2004, the prevalence of HIV was 0.5%, 1%, 3.2% and 19.9% in 15-49 year old whites, Indians, coloureds and blacks respectively. The risk factors which co-varied with HIV prevalence by race in the six surveys were age of sexual debut (in five out of five surveys for men and three out of six surveys for women), age gap (zero surveys in men and three in women), mean number of sex partners in the previous year (five surveys in men and three in women) and concurrent partnerships (five surveys in men and one in women). Condom usage and circumcision were both more prevalent in the high HIV prevalence groups. The reported prevalence of concurrency was 6 to 17 times higher in the black as opposed to the white men in the five surveys.
  
  
  CONCLUSIONS
  The differences in sexual behavior in general, and the prevalence of concurrency and the number of sexual partners in particular, offer a plausible and parsimonious cause to explain a part of the differing prevalences of HIV between South Africa's racial groups.
authors.affiliation: HIV/STD Unit, Institute of Tropical Medicine, Antwerp, Belgium. chriskenyon0@gmail.com
authors.forename: Chris
authors.initials: C
authors.lastname: Kenyon
authors.forename: Jozefien
authors.initials: J
authors.lastname: Buyze
authors.forename: Robert
authors.initials: R
authors.lastname: Colebunders
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002944:Circumcision, Male / Q000706:statistics & numerical data; D017280:Condoms / Q000706:statistics & numerical data; D003710:Demography; D005260:Female; D015658:HIV Infections / Q000453:epidemiology*; D006306:Health Surveys / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D044469:Racial Groups / Q000706:statistics & numerical data*; D012725:Sexual Behavior / Q000706:statistics & numerical data; D012747:Sexual Partners; D013019:South Africa / Q000453:epidemiology; D055815:Young Adult