Table 1 Sources for variables used in mathematical modeling

Proportion of PWID HIV- (I)

77.46 %

Petrar et al. [58]); Tyndall et al. [69]

Rate of Needle sharing (b) or (λ)

30 %

Holtgrave et al. [20]; Kerr et al. [37, 39]

Number of needles in circulation (N)

2000000

McClean [50]; Buxton [8]

Percentage of needles not cleaned (d)

17.00 %

Hope et al. [21]; Kaplan and O’Keefe [34]; Jacobs et al. [24]

Probability of HIV infections from a single injection (t) or (α)

0.67 %

Allard [1]; Kaplan and O’Keefe [34]

Number of sharing partners (m)

1.38

Kozal et al. [41]; Jacobs et al. [24]

Proportion of PWID HIV+ (q)

22.54 %

Holtgrave et al. [20]; Kerr et al. [37, 39]

Proportion PWID HCV- (I)

12.00 %

Bayoumi & Zaric [5]

Proportion of PWID HCV+ (q)

88.00 %

Bayoumi & Zaric [5]

Probability of HCV infection from single injection(t)

3 %

Gore & Bird [15]

Proportion of HIV/HCV infected needles (β)

40.50 %

Hope et al. [21]; Kaplan and O’Keefe [34])

Probability of needles cleaned (θ)

83 %

Iguchi & Bux [23]; Anderson et al. [2]; Kaplan and O’Keefe [34]); Jacobs et al. [24]