The mathematical epidemiological transmission model for HIV and HCV was applied to IDUs and NSPs specifically in the New South Wales. 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 the New South Wales with and without NSP distribution of sterile injecting equipment (Figure 30). The estimated number of infections averted is presented in Figure 31. An estimated 23,324 (15,392-30,819, IQR) HIV infections and 31,953 (31,096-33,657, IQR) HCV infections were averted due to NSPs in New South Wales.

Figure 30: Estimated HIV and HCV incidence in New South Wales with and without NSPs

Text equivalent below for Figure 30: Estimated HIV incidence in New South Wales with NSPsText equivalent below for Figure 30: Estimated HIV incidence in New South Wales without NSPsText equivalent below for Figure 30: Estimated HCV incidence in New South Wales with NSPsText equivalent below for Figure 30: Estimated HCV incidence in New South Wales without NSPs

Text version of Figure 30

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

Figure 30 consists of four graphs:
  • Estimated HIV incidence in New South Wales with NSPs

    • The 100 model simulations decrease gradually from a range of 12-28 in 1999 to 3-10 in 2009

    • The median of the model simulations decreases gradually from 29 in 1999 to 6 in 2009

    • The lower quartile of the model simulations decreases gradually from 15 in 1999 to 5 in 2009

    • The upper quartile of the model simulations decreases gradually from 22 in 1999 to 8 in 2009

    • The notification data for annual incidence of HIV in New South Wales is:

      • 1999 - 12
      • 2000 - 15
      • 2001 - 21
      • 2002 - 10
      • 2003 - 12
      • 2004 - 16
      • 2005 - 11
      • 2006 - 6
      • 2007 - 12

  • Estimated HIV incidence in New South Wales without NSPs

    • The 100 model simulations rise dramatically from almost 0 in 1999 to a range of 200-3,800 in 2003. By 2009, simulations range from 1,500 to above 5,000.

    • The median of the model simulations rises dramatically from almost 0 in 1999 to 4,600 in 2009.

    • The lower quartile of the model simulations rises dramatically from almost 0 in 1999 to 3,700 in 2009.

    • The upper quartile of the model simulations rises dramatically from almost 0 in 1999 passing 5,000 in 2007.

    • The notification data for annual incidence of HIV in New South Wales is consistently below 100 for all years between 1999 and 2007.

  • Estimated HCV incidence in New South Wales with NSPs

    • The 100 model simulations remain constant from 1998 to 2000 with a range of 4,000-5,800 before decreasing gradually to 3,000-4,000 in 2003. The range widens to 2,800-4,500 by 2009.

    • The median of the model simulations remains constant at 4,800 from 1998 to 2000, decreases gradually to 3,400 in 2003 and increases slightly to 3,600 in 2009.

    • The lower quartile of the model simulations remains constant at 4,700 from 1998 to 2000, decreases gradually to 3,200 in 2003 and increases slightly to 3,400 in 2009.

    • The upper quartile of the model simulations remains constant at 5,100 from 1998 to 2000, decreases gradually to 3,600 in 2003 and increases slightly to 3,800 in 2009.

    • The notification data for annual incidence of HCV in New South Wales is: Top of page
      • 1999 - 4,900
      • 2000 - 4,900
      • 2001 - 4,000
      • 2002 - 3,500
      • 2003 - 3,400
      • 2004 - 3,200
      • 2005 - 3,200

  • Estimated HCV incidence in New South Wales without NSPs

    • The 100 model simulations increase sharply from a range of 4,000-6,500 in 1998 to 12,000-16,000 in 1999, decrease slightly to 11,500-14,000 in 2000 and decrease sharply to 4,000-5,500 in 2002. The model simulations decrease further to 3,800-5,000 in 2003 before increasing gradually to 4,800-7,800 by 2009.

    • The median of the model simulations increases sharply from 4,800 in 1998 to 14,000 in 1999, decreases slightly to 12,300 in 2000 and decreases sharply to 4,500 in 2001. The median decreases further to 4,000 in 2003 before increasing gradually to 6,000 by 2009.

    • The lower quartile of the model simulations increases sharply from 4,800 in 1998 to 13,500 in 1999, decreases slightly to 12,000 in 2000 and decreases sharply to 4,100 in 2001. The lower quartile decreases further to 3,900 in 2003 before increasing gradually to 5,800 by 2009.

    • The upper quartile of the model simulations increases sharply from 4,800 in 1998 to 14,200 in 1999, decreases slightly to 12,800 in 2000 and decreases sharply to 4,800 in 2001. The upper quartile decreases further to 4,200 in 2003 before increasing gradually to 6,100 by 2009.

    • The notification data for annual incidence of HCV in New South Wales is:
      • 1999 - 4,900
      • 2000 - 4,900
      • 2001 - 4,000
      • 2002 - 3,500
      • 2003 - 3,400
      • 2004 - 3,200
      • 2005 - 3,200

Figure 31: Estimated cumulative number of HIV and HCV cases averted in New South Wales due to NSPs

Text equivalent below for Figure 31: Estimated cumulative number of HIV cases averted in New South Wales due to NSPsText equivalent below for Figure 31: Estimated cumulative number of HCV cases averted in New South Wales due to NSPs

Text version of Figure 31

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

Figure 31 consists of two graphs:
  • Expected cumulative number of HIV cases averted in New South Wales due to NSPs

    • With NSPs the cumulative number of HIV cases in New South Wales remains consistently below 100 for all years between 1999 and 2009.

    • Without NSPs the cumulative number of HIV cases in New South Wales increases exponentially from below 100 in 1999 to 7,000 in 2005 and rises above 10,000 by 2006.

  • Expected cumulative number of HCV cases averted in New South Wales due to NSPs

    • With NSPs the cumulative number of HCV cases in New South Wales increases gradually from below 5,000 in 1999 to 42,000 in 2009.

    • Without NSPs the cumulative number of HCV cases in New South Wales increases sharply from 14,000 in 1999 to 74,000 in 2009.