Background
Methods
Baseline prevalence levels of HIV/AIDS in Peru
Population | Population size (15 years +) | Details of estimation |
---|---|---|
MSM | 620,978* | Based on 2005 estimate [23] |
FSW | 25,500† | 2002 figure (average) based national aids programme report to UNAIDS[49] |
Pregnant women | 587,000‡ | 2005 Figures based on births per year[50] |
Remaining population | 26,040,522 | 2005 Figures from UN Population data base and calculated by subtracting populations from [50] |
The GOALS model
Input | Min | Max | Best fit | Source |
Percent of men 15-49 that are sexually active | 88.0 | 95.3 | 94.0 | |
Percent of women 15-49 that are sexually active | 74.8 | 95.5 | 91.0 | |
Sexually active 15-19 as % of 15-49 | 54.2 | 76.8 | 67.0 | [51] |
MSM | ||||
Input | Min | Max | Best fit | Source |
Percent of men in risk group | 0.0 | 15.0 | 3.2 | |
coital frequency (acts per year) | 30 | 70 | 35.7 | [13] |
number of partners per year | 1 | 6 | 1.2 | [39] |
Condom usage (percentage of acts) | 24.3 | 55.6 | 53.6 | [46] |
High risk men | ||||
Input | Min | Max | Best fit | Source |
Percent of men in risk group | 4.0 | 36.0 | 4.4 | |
coital frequency (acts per year) | 2 | 70 | 10.0 | |
number of partners per year | 2 | 89 | 2.5 | [13] |
Condom usage (percentage of acts) | 59.6 | 95.8 | 93.9 | [7] |
Medium risk men | ||||
Input | Min | Max | Best fit | Source |
Percent of men in risk group category | 5.0 | 16.0 | 12.4 | |
coital frequency (acts per year) | 30 | 70 | 31.0 | [13] |
number of partners per year | 2 | 5 | 2.2 | † |
Condom usage (percentage of acts) | 7.5 | 36.6 | 19.2 | [51] |
Low risk men | ||||
Input | Min | Max | Best fit | Source |
Percent of men in risk group category | * | * | * | * |
coital frequency (acts per year) | 30 | 70 | 38.9 | [13] |
number of partners per year | 1 | 2 | 1.1 | † |
Condom usage (percentage of acts) | 0.0 | 28.9 | 23.8 | [51] |
Partners per year Women (percentage of total female population aged 15-49 in risk group) | ||||
Input | Min | Max | Best fit | Source |
High risk (< 0.0%) | 500 | 1200 | 559.5 | |
Medium Risk (18.5%) | 1 | 3 | 1.5 | † |
Low risk (81.5%) | 1 | 2 | 1.0 | † |
MSM | ||||
Input | Min | Max | Best fit | Source |
HIV prevalence | 0.0 | 21.97 | 7.5 | |
Prevalence of ulcerative STIs* | 0.0 | 72.3 | 23.7 | [23] |
Prevalence of non-ulcerative STIs† | 0.0 | 6.3 | 5.2 | [53] |
Percent of STI cases treated | 84.1 | 87.1 | 85.3 | [51] |
High risk men | ||||
Input | Min | Max | Best fit | Source |
HIV prevalence | 0.7 | 13.8 | 7.3 | [54] |
Prevalence of ulcerative STIs* | 0.02 | 29.9 | 10.4 | |
Prevalence of non-ulcerative STIs† | 0.7 | 6.2 | 5.8 | [23] |
Percent of STI cases treated | 84.1 | 87.1 | 85.8 | [51] |
Medium risk men | ||||
Input | Min | Max | Best fit | Source |
HIV prevalence | 0.1 | 0.7 | 0.6 | [54] |
Prevalence of ulcerative STIs* | 1.0 | 15.2 | 6.8 | [54] |
Prevalence of non-ulcerative STIs† | 0.0 | 3.0 | 2.6 | Assumption |
Percent of STI cases treated | 84.1 | 87.1 | 84.3 | [51] |
Condom usage | ||||
Low risk men | ||||
Input | Min | Max | Best fit | Source |
HIV prevalence | 0.1 | 0.6 | 0.6 | |
Prevalence of ulcerative STIs* | 0.8 | 7 | 3.3 | [53] |
Prevalence of non-ulcerative STIs† | 0.0 | 4.7 | 2.8 | |
Percent of STI cases treated | 84.1 | 87.1 | 86.0 | [51] |
Women | ||||
Input | Min | Max | Best fit | Source |
HIV prevalence - FSW | 0.6 | 1.9 | 1.8 | [12] |
HIV prevalence - Medium | 0.1 | 1.9 | 0.5 | Assumption |
HIV prevalence - Low | 0.1 | 1.1 | 0.1 | [12] |
Calculating the costs of interventions
Modelling HIV Interventions effects in Peru
-
Mass media - media campaigns targeted at the general population. Costing is based on an average campaign price with four promotions per year - newspaper inserts delivered to 7% of the population, 52 TV emissions and 180 radio transmissions - reaching half of the adult population.
-
Voluntary counselling and testing - the number of tests required is equal to twice the number of people infected with HIV. It was assumed that people will request a new test every five years.
-
Peer counselling and treatment of sexually transmitted infections for female sex workers- the need is assumed to include all sex workers. Peer educators are trained by health professionals and provide condoms during counselling sessions.
-
Peer counselling and treatment of sexually transmitted infections for MSM - outreach programmes similar to peer counselling for sex workers - condoms are provided during counselling sessions.
-
Youth - includes children in the formal education system aged between 10 and 18. Sessions occur during normal school activities and are run by teachers who have undergone specific training.
-
Condoms - public sector condom distribution, male type only. Demand is calculated by sexually active population, proportion of sexually active population in high and medium risk groups, number of partners, and number of contacts per partner in each risk group. Condoms are included as part of other interventions including all peer education interventions and STI treatment.
-
STI treatment - Available to anyone requesting this activity. Prevalence rates are specified for each risk group in Table 3. Activity includes costs of treatment, counselling and condom provision. Drugs costs based on an average for treatment of urethral and vaginal discharge, genital ulcers and pelvic inflammatory disease.
-
Prevention of mother to child transmission - includes counselling pre and post test, and nevirapine for mother and child if accepted.
-
Highly active antiretroviral therapy - based on the three alternative treatment regimes proposed in a report addressing the implementation of an antiretroviral programme for Peru [1]. The basic programme includes: ARVS, Monitoring (CD4 + Viral Load). Intermediate programme is comprised of: Basic programme activities and imaging tests, additional lab monitoring, administrative costs. The comprehensive programme consists of: Intermediate programme activities and treatment of opportunistic infections.
Uncertainty Analysis
Ethics
Results
Estimated prevalence levels of HIV in Peru - baseline projection data
Costs per person reached for prevention and treatment of HIV/AIDs
STI treatment | $US |
Cost per STI case treated | 3.7 |
Youth
|
$US
|
Cost per youth reached by peer educator | 8.0 |
Cost per teacher trained | 62.0 |
Commercial sex worker
|
$US
|
Cost per sex worker reached | 124.0 |
Mass media
|
$US
|
Cost per person reached with mass media | 0.4 |
MSM
|
$US
|
Cost per person reached | 103.0 |
Voluntary counselling and testing
|
$US
|
Total costs per client | 40.0 |
Prevention of mother to child transmission
|
$US
|
Cost per mother and child treated | 23.2 |
Antiretroviral programmes*
|
$US
|
Basic† | 3379 |
Intermediate‡ | 3788 |
Comprehensive§ | 3792 |
Projections of the effects of interventions
Intervention | Coverage level (%) | Total costs ($ Millions) 2008-2013 | Yearly costs ($ Millions) | Total infections averted (2008-2013) | Yearly infections averted | Yearly DALYS averted | Average cost effectiveness - $/DALY averted (range*) |
---|---|---|---|---|---|---|---|
FSW | 50 | 0.6 | 0.1 | 1,970 | 394 | 10,118 | 55 (2 - 124) |
FSW | 95 | 1.0 | 0.2 | 3,730 | 746 | 19,157 | 55 (1 - 105) |
FSW | 80 | 0.9 | 0.1 | 3,130 | 626 | 16,076 | 55 (2 - 116) |
Blood safety | 50 | 5.3 | 0.9 | 13,050 | 2,610 | 67,025 | 79 (41 - 79) |
Blood safety | 80 | 8.5 | 1.4 | 20,570 | 4,114 | 105,648 | 80 (43 - 80) |
Blood safety | 95 | 10.1 | 1.7 | 24,260 | 4,852 | 124,599 | 81 (43 - 91) |
VCT | 95 | 8.2 | 1.4 | 13,870 | 2,774 | 71,236 | 116 (18 - 116) |
VCT | 50 | 4.4 | 0.7 | 7,300 | 1,460 | 37,493 | 118 (18 - 118) |
VCT | 80 | 7.1 | 1.2 | 11,670 | 2,334 | 59,937 | 118 (18 - 118) |
Youth: in-school | 50 | 13.7 | 2.3 | 21,760 | 4,352 | 131,126 | 104 (12 - 177) |
Youth: in-school | 80 | 22.0 | 3.7 | 22,760 | 4,552 | 137,152 | 161 (19 - 270) |
Youth: in-school | 95 | 26.2 | 4.4 | 23,020 | 4,604 | 138,719 | 189 (12 - 630) |
mass media | 50 | 11.3 | 1.9 | 8,930 | 1,786 | 45,864 | 246 (89 - 253) |
Condoms | 95 | 61.0 | 10.2 | 23,740 | 4,748 | 121,929 | 500 (64 - 500) |
Condoms | 80 | 51.3 | 8.6 | 19,890 | 3,978 | 102,155 | 503 (62 - 503) |
Condoms | 50 | 32.1 | 5.3 | 12,430 | 2,486 | 63,840 | 503 (58 - 503) |
STI treatment | 50 | 25.1 | 4.2 | 6,600 | 1,320 | 33,898 | 739 (200 - 1021) |
STI treatment | 80 | 40.1 | 6.7 | 10,290 | 2,058 | 52,849 | 759 (199 - 1045) |
STI treatment | 95 | 47.6 | 7.9 | 12,080 | 2,416 | 62,043 | 767 (200 - 1055) |
MSM | 50 | 75.0 | 12.5 | 11,090 | 2,218 | 56,958 | 1,317 (354 - 1317) |
MSM | 80 | 120.0 | 20.0 | 17,570 | 3,514 | 90,240 | 1,330 (351 - 1330) |
MSM | 95 | 142.5 | 23.8 | 20,770 | 4,154 | 106,675 | 1,336 (350 - 1336) |
HAART | |||||||
Comprehensive | 95 | 37.7 | 6.3 | - | - | 18917 | 1995 |
Intermediate | 95 | 37.7 | 6.3 | - | - | 16412 | 2297 |
Basic | 95 | 33.6 | 5.6 | - | - | 13999 | 2403 |
PMTCT | 80 | 246.4 | 41.1 | 10,460 | 2092 | 41,557 | 5,928 (2313 - 5.928) |