Table 1.
Summary of Key Model Parameters
| Parameter* | Value | Range |
|---|---|---|
| Demographic Parameters | ||
| Total MSM population age 13-64 | 6,435,210 | 5.5-7.5 million |
| HIV prevalence in MSM | 8.5% | 1-17% |
| Male mortality rate | 0.0043 | 0.003-0.005 |
| Male maturation rate | 0.0106 | 0.005-0.02 |
| Male entry rate | 0.022 | 0.01-0.04 |
| Disease Parameters | ||
| Average disease duration (years) | ||
| Acute HIV | 0.25 | 0.08-0.40 |
| Asymptomatic HIV | 7 | 6-10 |
| Symptomatic HIV | 3 | 1-4 |
| Symptomatic HIV – Treated with ART | 18 | 12-30 |
| AIDS | 2 | 1-3 |
| AIDS – Treated with ART | 5 | 2-15 |
| Sexual Behavior Parameters | ||
| Annual transmission probability per MSM partnership (MHIV+→MHIV−) |
||
| Acute HIV | 0.210 | 0.10-0.40 |
| Asymptomatic HIV | 0.039 | 0.02-0.08 |
| Symptomatic HIV | 0.039 | 0.02-0.08 |
| AIDS | 0.160 | 0.08-0.30 |
| Annual number of male partners | 3.0 | 2.0-5.0 |
| Condom usage with male partners | 40% | 30-60% |
| Treatment Parameters | ||
| Fraction of acutely infected starting ART after diagnosis | 50% | 0-100% |
| Fraction starting ART at CD4=350 cells/mm3 | 50% | 25-75% |
| Rate of initiating ART at CD4<350 cells/mm3 | 0.05 | 0-0.10 |
| Reduction in sexual infectivity due to ART | 90% | 50-99% |
| Screening Parameters | ||
| Fraction of population tested annually | 67% | 30-90% |
| Fraction of acutely infected who develop symptoms | 70% | 40-90% |
| Fraction of patients with influenza-like symptoms who seek medical attention |
35% | 10-100% |
| Identification duration if uninfected (years) | 1 | 0.5-3 |
| Reduction in sexual behavior due to testing and counseling | 20% | 0-50% |
| Cost Parameters (2009 US $) | ||
| Annual HIV-related healthcare costs | ||
| Acute HIV | 30 | 10-500 |
| Asymptomatic HIV – Untreated | 4,100 | 3,000-6,000 |
| Symptomatic HIV – Untreated | 6,883 | 5,000-9,000 |
| Symptomatic HIV – Treated with ART (excludes ART costs) | 6,136 | 5,000-7,000 |
| AIDS – Untreated | 21,700 | 15,000-25,000 |
| AIDS – Treated with ART (excludes ART costs) | 9,877 | 6,000-17,000 |
| Annual non-HIV-related healthcare costs | 4,028 | 3,000-6,000 |
| Annual cost of ART | 15,475 | 12,500-19,000 |
| Cost of HIV testing – VL test | ||
| Uninfected | 124 | 51-248 |
| HIV-Infected | 277 | 102-344 |
| Cost of HIV testing – antibody test | ||
| Uninfected | 13 | 5-25 |
| HIV-Infected | 67 | 50-100 |
| Cost of counseling | ||
| Pre-test counseling | 13 | 0-100 |
| Post-test counseling for HIV-negative persons | 7 | 0-50 |
| Post-test linkage/counseling for HIV-positive persons | 14 | 0-100 |
| Cost of HIV diagnosis | 500 | 125-1,200 |
| Discount Rate | 3% | 0-5% |
*
All rates are annual. See Appendix for sources. ART = antiretroviral treatment, MSM = men who have sex with men, VL = viral load