Immediacy and Magnitude of Impact
Adopting different age specific VMMC scale up strategies result in varied impacts on population levels of HIV incidence over the short and long terms. Figure 1 depicts the relative reduction in HIV incidence achieved by circumcising specific age groups compared with incidence in a population with no VMMC from 2015 to 2051. In these hypothetical scenarios, only males of the indicated age group are circumcised. The model shows that, over five years (point “a,” “immediacy of impact”), circumcising males ages 20 to 24, and 25 to 29 have the greatest impact on HIV incidence levels, and over 15 years (point “b,” “magnitude of impact”), circumcising males in the 15 to 19 and 20 to 24-year age bands will have the greatest impact. The period of 15 years (2016–2031, inclusive) was selected by a range of experts as it was considered long enough to discern appreciable impact in HIV incidence and short enough to be relevant to policymakers .
Efficiency and Cost Effectiveness
Efficiency in this analysis is defined as the number of circumcisions that would need to be performed in order to avert one HIV infection. Figure 2 presents the efficiency measures for each 5-year age group over a 15-year period in Namibia. Hypothetical scenarios were generated in which circumcisions are only performed on males of each specific five-year age group, and not broader groups inclusive of more than one five-year age band, with the infections averted then projected across the entire population. The figure indicates that the fewest circumcisions per HIV infection averted (IA) for the period (i.e. the most efficient), relative to the other strategies presented, would occur by circumcising 15- to 19-year-olds (63 VMMC/IA), 25- to 29-year-olds (56 VMMC/IA), and 20- to 24-year-olds (52 VMMC/IA).
The research team next considered the cost effectiveness of the national VMMC program in Namibia by comparing several different age prioritization strategies that may be adopted over the period 2016–2031. In this analysis, cost effectiveness was defined as the relative discounted cost per HIV IA, measured over a period of fifteen years, and assessed the cost-effectiveness of circumcising age groups broader than five years. Figure 3 demonstrates that the most cost-effective strategy (i.e. the lowest cost per HIV infection averted), relative to the other strategies presented, would be one that circumcises the age group 15 to 29 years, which reflected Namibia’s VMMC strategy at the time, or 15 to 34 years, each cost $6200/HIA. The cost effectiveness of strategies aimed at circumcising age groupings that were slightly narrower (15- to 24-years-old) or broader (15- to 49-years-old) were only incrementally more expensive, at $6700 and $6800 per IA, respectively. According to the model, circumcising males before age 15 is less cost effective as the majority of this age group are not yet sexually active. Therefore, there is a delay for any benefits on expenditure for VMMC service provision for this age group.
Circumcising Infants and Young Boys
To further inform the Ministry of Health and Social Service’s VMMC programing, the authors analyzed the potential benefits of incorporating EIMC and circumcision of young boys ages 10 to 14 years into the existing VMMC strategy. With the limited performance of the VMMC program in the years leading up to this application of the DMPPT 2.1, the analysis focused primarily on what adopting a strategy that introduces EIMC might achieve in terms of expanded coverage across age groups. While this analysis is treated in more detail elsewhere , Fig. 4 presents the three scenarios modelled to depict the coverage of various strategies to introduce EIMC into Namibia’s national VMMC program. The graphs show the estimated number of circumcisions that would have to be performed in each age group for the different scale-up scenarios starting in 2016. As the research team was not provided any historical program data (prior to 2015) the graphs do not depict circumcisions performed during this period.
Graph A in the figure represents a national VMMC scale-up strategy increasing coverage to 80% for 10- to 34-year-olds over five years and then sustaining it into the future. In this scenario, to reach target coverage by 2021 would require significant increases in annual VMMC service delivery of around 4- to 5-fold compared with 2015 program accomplishments. After the target year is reached, VMMC coverage is maintained by continuing to circumcise approximately 18,000 10- to 14-year-olds every year. Graph B builds on the strategy presented in Graph A but introduces EIMC into the national VMMC program and scales-up coverage to 80%. This approach would require a four- to six-fold increase in the annual number of VMMCs performed, until 2021, to reach the coverage target, amounting to well over 300,000 circumcisions over the five-year period. Sustaining this strategy would necessitate the circumcision, on average, of 24,000 infants annually. Graph C in the figure presents a strategy where EIMC is scaled up to a coverage of 40%. As with the other strategies, the same initial push of increasing the annual number of VMMCs performed by 4- to 5-fold is required here as well, until the target date of 2021. The total number of circumcisions required to reach set coverage is just over 330,000. Into the future, these would be maintained by conducting around 20,000 circumcisions annually, with a mix of around 60% infants and 40% 10 to 14-year-olds.
PEPFAR Age Prioritization Strategy
In 2016, PEPFAR issued new technical considerations for VMMC  that outlined a new strategic vision aimed at achieving the most immediate population-level impact from national VMMC programs. Such an impact would require a move from providing VMMC services to men ages 15 to 49 years to a narrower focus on circumcising males ages 15 to 29 years and scaling up to 60% coverage or more. Of course, promotion of such an implementation strategy is not meant to preclude the provision of circumcision services to males of other age groups, including boys 10- to 14-years old. This new policy direction from PEPFAR indicated that once the goal of reaching 60% coverage in the 15- to 29-year age groups had been reached, service provision to 10- to 14-year-olds could increase. Table 3 presents three VMMC coverage scenarios for Namibia that examines the effect of this policy guidance.
Scenario 1 represents the coverage that would be attained by strictly following the PEPFAR age prioritization. In this scenario, provision of VMMC to 15- to 29-year-olds is “aggressively” scaled up 50% above historical accomplishments, while circumcisions among 10- to 14-year-olds remain at 2015 levels. Net gains in coverage of 15- to 29-year-olds amounts to 22% point increase over 5 years. In comparison, Scenario 2, which keeps annual VMMC service provision to 15- to 29-year-olds constant and does not provide VMMC services to 10- to 14-year-olds, there is only an increase in coverage of 16% points among 15- to 29-year-olds over five years. Scenario 3 represents a more aggressive scenario and demonstrates what can be achieved if 15- to 29-year-olds are very aggressively circumcised (i.e., achieving numbers of VMMCs that were double the historical accomplishments), and if 10- to 14-year-olds are also targeted aggressively (achieving annual numbers of circumcisions that were 50% above historical accomplishments). In such a scenario, the National VMMC program in Namibia would be able to increase coverage among 15- to 29-year-olds by 27% points in 5 years and to a coverage of 50% at the end of 2021.
Table 4 presents a comparison of two VMMC scale up scenarios from 2016 to 2050 to assess the impact of adding EIMC to the national VMMC program in Namibia. In both scenarios, the VMMC scale up strategy is assumed to target expanding coverage among 10- to 34-year-olds only, while the other adds the introduction of EIMC. Scale up for each scenario is to reach 80% coverage within five years starting in 2016 and then maintaining that through to 2050, so as to ensure the timeframe of the model is sufficiently long to capture the impact of infant circumcision.
According to the analysis, adding EIMC to the national program, and scaling up to 80% coverage, increases the overall number of circumcisions needing to be performed over the period by 300,000 or 33% from a scale up strategy targeting 10- to 34-year-olds only. The number of infections averted over the period increases by 2000 or 7.6%, translating to an increase of 2% in new HIV infections averted. The number of VMMCs needing to be performed to avert a single infection experiences a 25.6% increase from 39 to 49. This is largely accounted for by the increase in the overall number of circumcisions the program needs to perform in order to achieve the coverage target, and the delay in sexual debut among circumcised infants.
An analysis of the cost and cost-effectiveness of adding EIMC to the national VMMC program is presented in Table 5. The authors conducted a sensitivity analysis looking at the effect on overall cost and cost-effectiveness when the costs for EIMC were set at 100, 50, and 25% of the costs of provision of adolescent and adult VMMC services.
As the data suggest, when the cost of EIMC is 100% of the cost of adolescent and adult VMMC, there is an increase of 25% in the total cost and 23% in the cost per infection averted if a target of 80% EIMC coverage is added to the national program over the period 2016 to 2050. However, if the cost of EIMC compared to adolescent and adult VMMC begins to fall, the model predicts more beneficial outcomes. For example, when the cost of EIMC if estimated at 50% of VMMC services, the total cost of the program, despite the increase in numbers being circumcised, actually decreases by 14%. If the cost of EIMC is estimated even lower, at 25% the cost of VMMC services, the total cost of the national program decreases by 40% relative to the total number being circumcised. Cost of EIMC also has implications for the effectiveness of the national program. With the cost of EIMC at 50% of VMMC, there is a decrease in cost per infection averted from $5163 to $4606. A further reduction in the cost of EIMC makes the program more effective reducing the cost per infection averted to $3646.
VMMC Program Gains
After a year of VMMC program implementation in Namibia following our initial modelling analysis, the authors assessed any changes that occurred in the annual number of VMMC performed by age group. Figure 5 presents a comparison of VMMCs performed by age group and year for 2015–2017, with 2017 being the first year after the modeling exercise was conducted. The program data show a substantial increase in VMMCs performed across all age groups from 10 to 34 years. This increase is most dramatic in the age group 10 to 14, where there was more than a 20-fold increase in clients circumcised from 2016 to 2017. In the 15- to 19-year age group, productivity more than doubled over the same period. A doubling of circumcision volumes also occurred in the 20 to 24, 25 to 29, and 30 to 34-year age groups.