Table 2.
Percentage of cumulative infections prevented over 20 years with population vaccination coverage levels maintained over time in Soweto: Sensitivity analysis on population coverage levels achieved and post-vaccination changes in condom use behaviorsa
| Risk behavior change and time period for measurement of program outcomes b | Population coverage maintained over time c |
||
|---|---|---|---|
| 30% | 60% | 90% | |
| No change in condom use behavior | |||
| 5 years | 21% | 33% | 41% |
| 10 years | 27% | 41% | 50% |
| 15 years | 31% | 46% | 55% |
| 20 years | 34% | 50% | 59% |
| Condom use behavior increases by 50% post-vaccination | |||
| 5 years | 24% | 37% | 46% |
| 10 years | 31% | 47% | 55% |
| 15 years | 36% | 52% | 61% |
| 20 years | 39% | 56% | 65% |
| Condom use behavior decreases by 50% post-vaccination | |||
| 5 years | 17% | 29% | 36% |
| 10 years | 23% | 35% | 44% |
| 15 years | 26% | 40% | 49% |
| 20 years | 29% | 44% | 53% |
Percentages reflect the proportion of cumulative expected adult infections prevented by each program scenario compared with a no vaccine baseline. All simulations assume vaccine efficacy and average duration of protection calculated from RV144 trial data.
Simulations assume initial vaccination of population at time zero and outcomes calculated at 5, 10, 15 and 20 year intervals. Post-vaccination changes in condom use (increase or decrease by 50%) assume change in male-negotiated condom use in vaccinated individuals.
Population coverage refers to the proportion of the adult population which is effectively vaccinated. Individuals are vaccinated or revaccinated over time to maintain the specified overall population coverage level.