Table A-3.
Summary of key model parameters.
| Parameter | Value | Range | Source |
|---|---|---|---|
| Demographics | |||
| Total population (15 to 64 years) | |||
| Male IDU | 1,000,000 | 0.5-1.5 million | Calculated [19-23] |
| Male MSM | 4,057,194 | 3-6 million | Calculated [19-21, 24] |
| Male IDU/MSM | 300,000 | 200,000-500,000 | Calculated [17, 19-25] |
| Male Other | 96,022,652 | 95-100 million | Calculated [19-21] |
| Female IDU | 450,000 | 300,00-600,000 | Calculated [19-23] |
| Female Other | 101,632,781 | 100-105 million | Calculated [19-21] |
| HIV prevalence | |||
| Male IDU | 12.9% | 10-20% | Calculated [19-23] |
| Male MSM | 12.6% | 5-20% | Calculated [19-21, 24] |
| Male IDU/MSM | 18.8% | 15-30% | Calculated [19-25] |
| Male Other | 0.10% | 0.05-0.25% | Calculated [19-21] |
| Female IDU | 17.3% | 15-30% | Calculated [19-23] |
| Female Other | 0.22% | 0.10-0.40% | Calculated [19-21] |
| Annual mortality rate | |||
| Male | 0.0041 | 0.002-0.005 | [26] |
| Female | 0.0024 | 0.002-0.005 | [26] |
| IDU (excess) | 0.025 | 0-0.05 | [27] |
| Annual maturation rate | |||
| Male | 0.0111 | 0.01-0.02 | [21] |
| Female | 0.0122 | 0.01-0.02 | [21] |
| Annual entry rate | |||
| Male | 0.0227 | 0.01-0.05 | [21] |
| Female | 0.0213 | 0.01-0.05 | [21] |
| Sexual Transmission | |||
| Transmission probability per partnership | |||
| Heterosexual (FHIV+→MHIV−) | |||
| Asymptomatic HIV | 0.02 | 0.01-0.04 | [28-36] |
| Symptomatic HIV | 0.03 | 0.01-0.04 | [28-36] |
| AIDS | 0.05 | 0.03-0.06 | [28-36] |
| Heterosexual (MHIV+→FHIV−) | |||
| Asymptomatic HIV | 0.03 | 0.02-0.05 | [28-36] |
| Symptomatic HIV | 0.04 | 0.02-0.05 | [28-36] |
| AIDS | 0.08 | 0.05-0.10 | [28-36] |
| Homosexual (MHIV+→MHIV−) | |||
| Asymptomatic HIV | 0.04 | 0.03-0.06 | [32, 37-39] |
| Symptomatic HIV | 0.05 | 0.03-0.06 | [32, 37-39] |
| AIDS | 0.10 | 0.08-0.15 | [32, 37-39] |
| Annual number of same-sex partners | |||
| Male MSM | 3.0 | 2.0-5.0 | [40-43] |
| Male IDU/MSM | 3.0 | 2.0-5.0 | [40, 41, 43] |
| Condom usage with same-sex partners | |||
| Male MSM | 40% | 30-60% | [25, 40-43] |
| Male IDU/MSM | 40% | 30-50% | [43] |
| Annual number of opposite-sex partners | |||
| Male IDU | 3.0 | 2.0-5.0 | [44] |
| Male MSM | 0.1 | 0-1.0 | [42] |
| Male IDU/MSM | 0.1 | 0-1.0 | [45] |
| Male Other | 1.1 | 0.5-2.0 | [42, 46-49] |
| Female IDU | 3.5 | 2.0-5.0 | [50] |
| Female Other | 1.1 | 0.5-2.0 | [46, 47, 49, 51] |
| Condom usage with opposite-sex partners | |||
| Male IDU | 25% | 15-35% | [25, 45] |
| Male MSM | 30% | 20-50% | [25, 43] |
| Male IDU/MSM | 30% | 30-50% | [43, 45] |
| Male Other | 20% | 10-40% | [46] |
| Female IDU | 25% | 20-50% | [44, 50] |
| Female Other | 20% | 10-40% | [46] |
| Reduction in heterosexual HIV transmission due to male circumcision |
50% | 48-60% | [52-54] |
| Injection Drug Use Transmission | |||
| Transmission probability per shared injection | |||
| Asymptomatic HIV | 0.002 | 0.001-0.005 | [27, 55, 56] |
| Symptomatic HIV | 0.003 | 0.001-0.005 | [27, 55, 56] |
| AIDS | 0.003 | 0.001-0.005 | [27, 55, 56] |
| Average injections per year | 200 | 100-500 | [27, 57] |
| Fraction of injections that are shared | 20% | 10-40% | [27, 43, 44, 58] |
| HIV Screening | |||
| Fraction of population tested in past 12 months | |||
| High-risk individuals | 23% | 10-30% | [20] |
| Low-risk individuals | 10% | 5-20% | [20] |
| Annual probability of symptom-based case finding | |||
| HIV | 10% | 0-30% | [16] |
| AIDS | 20% | 10-60% | [16] |
| Reduction in sexual behavior among HIV+ identified individuals due to screening |
20% | 0-50% | [59-62] |
| Antiretroviral Therapy (ART) | |||
| Fraction starting ART at CD4=350 cells/mm3 | 50% | 25-75% | Assumed [63, 64] |
| Annual ART entry rate if CD4<350 cells/mm3 | 0.05 | 0-0.10 | Assumed [64] |
| Reduction in injection infectivity due to ART | 50% | 25-75% | [16, 65] |
| Reduction in sexual infectivity due to ART | 90% | 50-99% | [35, 66-71] |
| Circumcision | |||
| Fraction of males circumcised | 70% | 50-80% | [72] |
| Reduction in HIV transmission due to circumcision |
50% | 48-60% | [53, 54] |
| Quality-of-life Multipliers | |||
| Uninfected | 1.0 | --- | [73] |
| Asymptomatic HIV – Unaware | 0.91 | 0.85-0.95 | [74-77] |
| Asymptomatic HIV – Aware (Year 1) | 0.84 | 0.85-0.95 | [16, 74-77] |
| Asymptomatic HIV – Aware (Years 2+) | 0.89 | 0.85-0.95 | [16, 74-77] |
| Symptomatic HIV – Unaware | 0.79 | 0.70-0.80 | [74-77] |
| Symptomatic HIV – Aware | 0.72 | 0.70-0.80 | [74-77] |
| Symptomatic HIV – Treated with ART | 0.83 | 0.82-0.87 | [74-77] |
| AIDS – Unaware | 0.72 | 0.60-0.75 | [74-77] |
| AIDS – Aware | 0.72 | 0.60-0.75 | [74-77] |
| AIDS – Treated with ART | 0.82 | 0.82-0.87 | [74-77] |
| IDU (multiplier)* | 0.90 | 0.80-1.0 | [27, 65] |
| Costs (2009 USD) | |||
| Annual HIV-related healthcare costs | |||
| Asymptomatic HIV – Untreated | $4,125 | $3,000-$6,000 | [78, 79] |
| Symptomatic HIV – Untreated | $6,925 | $5,000-$9,000 | [78, 79] |
| Symptomatic HIV – Treated with ART | $6,174 | $5,000-$7,000 | [78, 79] |
| AIDS – Untreated | $21,838 | $15,000-$25,000 | [78-80] |
| AIDS – Treated with ART | $9,938 | $6,000-$17,000 | [16, 79] |
| Annual non-HIV-related healthcare costs | $7,576 | $5,000-$8,000 | [81] |
| Annual cost of ART | $15,571 | $12,000-$18,000 | [16, 79, 80, 82] |
| Cost of HIV ELISA antibody test | $12 | $10-20 | [83] |
| Cost of confirmatory Western Blot test | $19 | $10-50 | [83] |
| Cost of behavior counseling | $60 | $50-$100 | [16, 82, 84] |
| Annual cost of ancillary IDU services | $2,500 | $1,000-$4,000 | [27] |
| Annual discount rate | 3% | 0-5% | [13] |
*
Quality of life for all injection drug users is multiplied by this quantity.
ART = antiretroviral therapy; ELISA = enzyme-linked immunosorbent assay;
MSM = men who have sex with men; IDU = injection drug user;
FHIV+→MHIV− = HIV transmission between HIV+ female partner and HIV− male partner;
MHIV+→FHIV− = HIV transmission between HIV+ male partner and HIV− female partner;
MHIV+→MHIV− = HIV transmission between HIV+ male partner and HIV− male partner;
USD = United States dollars.