title: Heterosexual HIV transmission and STD prevalence: predictions of a theoretical model.
abstract: BACKGROUND
  Previous studies suggest that concurrent sexually transmitted infection may enhance HIV transmission. This paper explores some theoretical consequences of this using a mathematical model of transmission of HIV and other STD pathogens.
  
  
  OBJECTIVE
  To develop a deterministic mathematical model to describe the heterosexual transmission dynamics of both HIV and a bacterial STD.
  
  
  METHODS
  We used survey derived estimates of sexual behaviour in a young heterosexual London population in our deterministic mathematical model to estimate the effects on an HIV epidemic of different levels of STD prevalence in such a population.
  
  
  RESULTS
  We show that the predictions of the model are plausible and suggest that, even under conditions both of low STD prevalence and of low HIV transmission enhancement, a substantial proportion of HIV transmission events may be attributable to concurrent STD.
  
  
  CONCLUSIONS
  It is likely that epidemics of heterosexually transmitted HIV infection in industrialised countries have been limited in size by the relative success of efforts to control STD. None the less, a significant proportion of heterosexual transmission events which do occur may be attributable to concurrent STD. In developing countries, cheap and simple STD care is likely to be a highly cost effective strategy to prevent HIV transmission.
authors: Department of Social Science and Medicine, Imperial College School of Medicine, London.
authors: A M
authors: AM
authors: Renton
authors: L
authors: L
authors: Whitaker
authors: M
authors: M
authors: Riddlesdell
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004196:Disease Outbreaks; D005260:Female; D005544:Forecasting; D015658:HIV Infections / Q000453:epidemiology / Q000635:transmission; D020010:Heterosexuality; D006801:Humans; D008131:London / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D015995:Prevalence; D012749:Sexually Transmitted Diseases / Q000453:epidemiology / Q000635:transmission*