Table 6. Ten-year cumulative health outcomes, program costs and cost-effectiveness for alternative dog rabies vaccination programs in East Africa, by risk of rabies transmission.a.
| Item | No vaccination | 10 year impact of vaccination programs: Per million population a, b | |
|---|---|---|---|
| Option 1: 50% dog population, annual | Option 2: 20% dog population, biannual | ||
| Rabies dog-dog rabies transmission risk c | |||
| Low-high | Low-high | Low-high | |
| A. Effectiveness of the intervention (undiscounted) | |||
| Number of rabid dogs | 43,868–64,533 | 1,307–16,771 | 2,669–14,192 |
| Number of rabid dogs averted | NA | 42,562–47,762 | 41,200–50,341 |
| Percentage reduction in rabid dogs | NA | 97%-74% | 94%-78% |
| Human rabies deaths | 2,132–2,904 | 63–1,263 | 126–964 |
| Human rabies deaths averted | NA | 2,069–1,641 | 2,006–1,940 |
| Percentage reduction in human deaths | 97%-57% | 94%-67% | |
| Years of life gained (YLG) | NA | 118,269–97,364 | 112,382–110,150 |
| B. Cost of the intervention (undiscounted, US$) | |||
| Dog vaccine administration (include biologics) | 0–0 | 1,128,954–960,160 | 897,406–767,903 |
| Spade and Neuter costs | 0–0 | 120,453–102,444 | 119,685–102,414 |
| Post-exposure prophylaxis (PEP) | 410,751–563,894 | 112,107–157,562 | 216,759–300,418 |
| Investigation suspected rabid dog costsd | 25,207–34,605 | 6,880–9,669 | 13,302–18,436 |
| Total costs | 435,958–598,499 | 1,368,394–1,229,835 | 1,247,152–1,189,171 |
| C. Average cost-effectiveness compared to no mass vaccination | |||
| Undiscounted | |||
| Cost per human death averted (US$/death) | NA | 451–385 | 404–305 |
| Cost per year of life gained (US$/YLG) | NA | 8–6 | 7–5 |
| Discounted at 3%e | |||
| Cost per human death averted (US$/death) | NA | 460–368 | 415–299 |
| Cost per year of life gained (US$/YLG) | NA | 17–13 | 16–11 |
| Discounted at 16%e | |||
| Cost per human death averted (US$/death) | NA | 509–327 | 468–290 |
| Cost per year of life gained (US$/YLG) | NA | 103–64 | 98–60 |
a. Results for two scenarios for dog rabies vaccination programs in an East African population of 1 million persons (approximately 2/3 urban, 1.3 rural), with approximately 82,000 dogs (Table 1).
b. Vaccination programs: Option 1, annual mass dog vaccination, resulting in 50% of the dog population vaccinated, and Option 2, biannual (twice per year) mass dog vaccination, resulting in 20% of the dog population vaccinated each time a vaccination program is run.
c. Rabies transmission risk is defined by number of bites per rabid dog to another dog (see Table 2).
d. Suspect rabies exposure costs are those costs associated with investigating a dog suspected of having rabies and investigating any bites on humans associated with that animal. Further details, see Tables 3 and 4 and main text.
e. 3% and 16% discount rate applied to both health outcomes and costs. US$ denotes 2015 US dollars. The 16% discount rate was derived from the weighted average yield to maturity for 10 year Bank of Tanzania Treasury bonds in October 2017. (https://www.bot.go.tz/financialmarkets/aspSmartUpload/TBondsResults.asp: accessed May 10, 2018)