Decline in HIV prevalence among young women in Zambia: national-level estimates of trends mask geographical and socio-demographic differences

PLoS One. 2012;7(4):e33652. doi: 10.1371/journal.pone.0033652. Epub 2012 Apr 4.

Abstract

Background: A decline in HIV incidence has been reported in Zambia and a number of other sub-Saharan countries. The trend of HIV prevalence among young people is a good marker of HIV incidence. In this study, different data sources are used to examine geographical and sub-population group differentials in HIV prevalence trends among men and women aged 15-24 years in Zambia.

Design and methods: We analysed ANC data for women aged 15-24 years from 22 sentinel sites consistently covered in the period 1994-2008, and HIV data for young men and women aged 15-24 years from the ZDHS 2001/2 and 2007. In addition, we systematically reviewed peer-reviewed articles that have reported findings on HIV prevalence and incidence among young people.

Findings: Overall trends of the ANC surveillance data indicated a substantial HIV prevalence decline among young women in both urban and rural areas. However, provincial declines differed substantially, i.e. between 10% and 68% among urban women, and from stability to 86% among rural women. Prevalence declines were steeper among those with the highest educational attainments than among the least educated. The ZDHS data indicated a significant reduction in prevalence between the two survey rounds among young women only. Provincial-level ZDHS changes were difficult to assess because the sample sizes were small. ANC-based trend patterns were consistent with those observed in PMTCT-based data (2002-2006), whereas population-based surveys in a selected urban community (1995-2003) suggested that the ANC-based data underestimated the prevalence declines in the general populations of both young both men and women.

Conclusion: The overall HIV prevalence declined substantially among young women in Zambia and this is interpreted as indicating a decline in HIV incidence. It is noteworthy that overall national trends masked substantial differences by place and by educational attainment, demonstrating critical limitations in the current focus on overall country-level trends in epidemiological reports.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Demography
  • Educational Status
  • Female
  • HIV
  • HIV Infections / epidemiology*
  • HIV Seropositivity / epidemiology*
  • Humans
  • Pregnancy
  • Pregnancy Complications, Infectious / epidemiology*
  • Prevalence
  • Rural Population
  • Sentinel Surveillance
  • Socioeconomic Factors
  • Young Adult
  • Zambia / epidemiology