Incidence of HIV-1 infection and changes in prevalence of reproductive tract infections and sexual risk behaviours: a population-based longitudinal study in rural Tanzania

  • Elia J Mmbaga Department of General Practice and Community Medicine, Faculty of Medicine, University of Oslo, PO Box 1046, Blindern 0318, Oslo, Norway; Departments of Epidemiology and Biostatistics, Muhimbili University College of Health Sciences, PO Box 65015, Dar es
  • Akhtar Hussain Department of General Practice and Community Medicine, Faculty of Medicine, University of Oslo, PO Box 1046, Blindern 0318, Oslo, Norway
  • Germana H Leyna Departments of Epidemiology and Biostatistics, Muhimbili University College of Health Sciences, PO Box 65015, Dar es Salaam, Tanzania; Department of Nutrition, Faculty of Medicine, University of Oslo, PO Box 1046, Blindern 0318, Oslo, Norway
  • Elise Klouman Norwegian Institute of Public Health, Division of Infectious Disease Control, PO Box 4404, Nydalen 04030, Oslo, Norway
  • Elisante Masenga Kilimanjaro Christian Medical Centre, PO Box 3010, Moshi, Tanzania
  • Noel Sam Kilimanjaro Christian Medical Centre, PO Box 3010, Moshi, Tanzania
  • Kagoma S Mnyika Departments of Epidemiology and Biostatistics, Muhimbili University College of Health Sciences, PO Box 65015, Dar es Salaam, Tanzania
  • Knut-Inge Klepp Department of Nutrition, Faculty of Medicine, University of Oslo, PO Box 1046, Blindern 0318, Oslo, Norway
Keywords: Africa, bacterial vaginosis, candidiasis, chlamydia, epidemiological synergy, gonorrhoea, incidence, sequelae

Abstract

This study aimed at describing the prevalence and incidence of HIV-1 and change in the prevalence of reproductive tract infections (RTIs) and sexual risk behaviours in the rural Kilimanjaro region of Tanzania. Two cross-sectional surveys among the total village population of Oria were conducted in 1991 and 1993. All individuals with a permanent address in the village were registered and invited to participate. After informed consent, participants gave blood for HIV-1 testing. Participants aged 15–44 years were interviewed regarding their socio-demographic characteristics and sexual risk behaviours and underwent genital examination and testing for RTIs. In 1991 and 1993, respectively, 3 239 (83.6%) and 2 191 (76.9%) individuals in the village participated. Prevalence of HIV-1 increased from 1.3% to 1.8%, but the difference was not significant (p = 0.17). HIV-1 incidence was 13.0/1000 person-years-at-risk (PYAR) for women and 4.3/1000 PYAR for men (relative risk was 3.0; 95% CI: 1.12–8.16). There was a significant increase in the prevalence of gonorrhoea, bacterial vaginosis and vaginal candidiasis (p < 0.001). The percentage of individuals who reported having multiple sexual partners during the 12 months preceding the survey increased from 12.9% to 24.1% (p < 0.001). The results suggest that RTIs and HIV-1 infections increased in this population in the early 1990s. Women were at higher risk of HIV-1 infection as compared to men. Sexual risk behaviours and RTIs may have contributed to HIV-1 transmission in this community. The data collected may help to inform the future design and evaluation of various intervention measures.

Keywords: Africa, bacterial vaginosis, candidiasis, chlamydia, epidemiological synergy, gonorrhoea, incidence, sequelae

African Journal of AIDS Research 2006, 5(3): 281–288
Published
2008-02-11
Section
Articles

eISSN: 1608-5906