The epidemiological transmission model for HIV and HCV was applied to IDUs and NSPs specifically in Western Australia. The model was used to evaluate current NSPs versus no program and to project likely epidemiological impacts of potential changes to the program. The model estimated the expected number of HIV and HCV cases in Western Australia with and without NSP distribution of sterile injecting equipment (Figure 60). The estimated number of infections averted is presented in Figure 61. An estimated 895 (564-1522, IQR) HIV infections and 12,625 (12,255-12,929, IQR) HCV infections were averted due to NSPs in Western Australia.

Figure 60: Estimated HIV and HCV incidence in Western Australia with and without NSPs

Text equivalent below for Figure 60: Estimated HIV incidence in Western Australia with NSPsText equivalent below for Figure 60: Estimated HCV incidence in Western Australia without NSPsText equivalent below for Figure 60: Estimated HCV incidence in Western Australia with NSPsText equivalent below for Figure 60: Estimated HCV incidence in Western Australia  without NSPs

Text version of Figure 60

Top of pageFigures in this description are approximate as they have been read from the graph.

Figure 60 consists of four graphs:
  • Estimated HIV incidence in Western Australia with NSPs

    • The 100 model simulations decrease gradually from a range of 2.4-4.6 in 1999 to 0.8-1.8 in 2009.

    • The median of the model simulations decreases gradually from 3.4 in 1999 to 1 in 2009.

    • The lower quartile of the model simulations decreases gradually from 2.9 in 1999 to 0.9 in 2009.

    • The upper quartile of the model simulations decreases gradually from 3.8 in 1999 to 1.1 in 2009.

    • The notification data for annual incidence of HIV in Western Australia is:
      • 1999 - 1
      • 2000 - 1
      • 2001 - 1
      • 2002 - 2
      • 2003 - 2
      • 2004 - 2
      • 2005 - 1
      • 2006 - 4
      • 2007 - 0

  • Estimated HIV incidence in Western Australia without NSPs

    • The 100 model simulations rise dramatically from a range of 0-30 in 1999 to 20-255 in 2003. By 2009, simulations range from 30 to above 300.

    • The median of the model simulations rises dramatically from 5 in 1999 to 170 in 2009.

    • The lower quartile of the model simulations rises dramatically from 3 in 1999 to 95 in 2009.

    • The upper quartile of the model simulations rises dramatically from 10 in 1999 to 270 in 2009. Top of page

    • The notification data for annual incidence of HIV in Western Australia is consistently below 5 for all years between 1999 and 2007.

  • Estimated HCV incidence in Western Australia with NSPs

    • The 100 model simulations decrease gradually from a range of 1,200-1,300 in 1999 to 550-650 in 2009.

    • The median of the model simulations decreases gradually from 1,250 in 1999 to 600 in 2009.

    • The lower quartile of the model simulations decreases gradually from 1,225 in 1999 to 625 in 2009.

    • The upper quartile of the model simulations decreases gradually from 1,275 in1999 to 575 in 2009.

    • The notification data for annual incidence of HCV in Western Australia is:
      • 1999 - 1,200
      • 2000 - 1,250
      • 2001 - 1,000
      • 2002 - 850
      • 2003 - 850
      • 2004 - 800
      • 2005 - 800

  • Estimated HCV incidence in Western Australia without NSPs

    • The 100 model simulations increase sharply from a range of 1,200-2,300 in 1998 to 4,200-5,900 in 1999, decrease sharply to 1,800-2,500 in 2002 and decrease gradually to 1,000-1,800 in 2008. The model simulations then increase slightly to 1,100-1,900 by 2009.

    • The median of the model simulations increases sharply from 1,800 in 1998 to 5,400 in 1999, decreases sharply to 2,200 in 2002. The median then decreases gradually to 1,400 in 2007 before increasing gradually to 1,650 in 2009.

    • The lower quartile of the model simulations increases sharply from 1,700 in 1998 to 5,200 in 1999, decreases sharply to 2,000 in 2002 and decreases gradually to 1,200 in 2007 before increasing gradually to 1,600 in 2009.

    • The upper quartile of the model simulations increases sharply from 2,100 in 1998 to 5,600 in 1999, decreases sharply to 2,200 in 2002 and decreases gradually to 1,500 in 2008 before increasing gradually to 1,700 in 2009.

    • The notification data for annual incidence of HCV in Western Australia is:
      • 1999 - 1,200
      • 2000 - 1,250
      • 2001 - 1,000
      • 2002 - 850
      • 2003 - 850
      • 2004 - 800
      • 2005 - 800Top of page

Figure 61: Estimated cumulative number of HIV and HCV cases averted in Western Australia due to NSPs

Text equivalent below for Figure 61: Estimated cumulative number of HIV cases averted in Western Australia due to NSPsText equivalent below for Figure 61: Estimated cumulative number of HCV cases averted in Western Australia due to NSPs

Text version of Figure 61

Figures in this description are approximate as they have been read from the graph.

Figure 61 consists of two graphs:
  • Expected cumulative number of HIV cases averted in Western Australia due to NSPs

    • With NSPs (current coverage) the cumulative number of HIV cases in Western Australia increases slightly from about 0 in 1999 to 20 in 2009.

    • Without NSPs the cumulative number of HIV cases in Western Australia increases exponentially from below 10 in 1999 to 950 in 2009.

  • Expected cumulative number of HCV cases averted in Western Australia due to NSPsTop of page

    • With NSPs (current coverage) the cumulative number of HCV cases in Western Australia increases gradually from 3,000 in 1999 to 13,000 in 2009.

    • Without NSPs the cumulative number of HCV cases in Western Australia increases sharply from 5,000 in 1999 to 26,000 in 2009.