Elimination of Dog-Mediated Human Rabies Deaths by 2030: Needs Assessment and Alternatives for Progress Based on Dog Vaccination

Abstract

Background: Rabies imposes a substantial burden to about half of the world population. The World Health Organization (WHO), World Organization for Animal Health, and the Food and Agriculture Organization have set the goal of eliminating dog-mediated human rabies deaths by 2030. This could be achieved largely by massive administration of post-exposure prophylaxis-in perpetuity-, through elimination of dog rabies, or combining both. Here, we focused on the resources needed for the elimination of dog rabies virus by 2030.

Materials and methods: Drawing from multiple datasets, including national dog vaccination campaigns, rabies literature, and expert opinion, we developed a model considering country-specific current dog vaccination capacity to estimate the years and resources required to achieve dog rabies elimination by 2030. Resources were determined based on four factors: (a) country development status, (b) dog vaccination costs, (c) dog rabies vaccine availability, and (d) existing animal health workers. Our calculations were based on the WHO's estimate that vaccinating 70% of the dog population for seven consecutive years would eliminate rabies.

Findings: If dog rabies vaccine production remains at 2015 levels, we estimate that there will be a cumulative shortage of about 7.5 billion doses to meet expected demand to achieve dog rabies elimination. We estimated a present cost of $6,300 million to eliminate dog rabies in all endemic countries, equivalent to a $3,900 million gap compared to current spending. To eliminate dog rabies, the vaccination workforce may suffice if all public health veterinarians in endemic countries were to dedicate 3 months each year to dog rabies vaccination. We discuss implications of potential technology improvements, including population management, vaccine price reduction, and increases in dog-vaccinating capacities.

Conclusion: Our results highlight the resources needed to achieve elimination of dog-mediated human rabies deaths by 2030. As exemplified by multiple successful disease elimination efforts, one size does not fit all. We suggest pragmatic and feasible options toward global dog rabies elimination by 2030, while identifying several benefits and drawbacks of specific approaches. We hope that these results help stimulate and inform a necessary discussion on global and regional strategic planning, resource mobilization, and continuous execution of rabies virus elimination.

Keywords: dog vaccination; global health; infectious disease; one health; population management; rabies control and prevention; rabies elimination; zoonotic diseases.

Figure 1

Global Dog Rabies Elimination Pathway (GDREP): phases for a dog rabies elimination program based on 70% dog population vaccination coverage. Notes: there is variation between and within countries for the implementation and scaling-up of national dog vaccination campaigns. Based on expert opinion from dog vaccine implementation strategies in Haiti, Ethiopia, United States, Vietnam, and Latin America, we assumed that the current dog rabies vaccination coverage was directly correlated to the number of years it will take to achieve elimination, as illustrated by the three distinct phases shown in the figure. For countries in Phase II, we estimated dog vaccination as the median value in the corresponding year range (e.g., we used 26% vaccination coverage in the rage 18–35%), or the current country vaccination rate for those countries that were already vaccinating dogs at a rate equivalent to Phase II. *Infrastructural improvement costs were estimated to be equivalent to the cost of vaccination for 10% of the country’s unvaccinated dog population.

Figure 2

Annual dog vaccinations required to achieve rabies elimination goal by 2030. Notes: the estimates show aggregate values of canine vaccination requirements for countries, assuming that all countries begin working toward rabies elimination in the first year. The estimates are based on current human and dog population and vaccine availability.

Figure 3

Global annual costs of dog rabies vaccine administration to achieve dog rabies elimination in endemic countries, and number of countries with endemic rabies. Notes: costs are in 2015 US dollars; we used a 3% discount rate (45).

Figure 4

Variability of the aggregate costs of GDREP based on the costs of administering rabies vaccines to 70% of the dog population, in rabies endemic countries, for a range of unit costs per dog vaccinated. Notes: costs are in 2015 US dollars; we used a 3% discount rate (45). Unit costs per dog vaccinated were informed by previous economic studies of dog vaccination (, –44, 49). GDREP denotes Global Dog Rabies Elimination Pathway.

Figure 5

Annual surplus or deficit of global dog vaccination capacity (total dogs potentially vaccinated by existing workforce) to achieve rabies elimination in dog rabies endemic countries based on (A) public health veterinary workforce and (B) public health para-veterinary workforce. Notes: workforce data were obtained from the World Organization for Animal Health (40); the vaccination capacity was estimated for each country with dog endemic rabies and then aggregated at the global level. The estimates are based on a dog vaccination capacity of 100 dogs per worker per day (39).

Figure 6

Annual costs of dog rabies control under four hypothetical scenarios: decrease in the price of dog rabies vaccine, (including syringe and needle) increases in daily vaccination capacity of health workers, and effective dog population management and control. Notes: the four hypothetical scenarios assuming that a new technology impacted the feasibility of dog vaccination, reasonably improving current practices. The estimates are based on current human and dog population and vaccine availability. The distribution of aggregate costs components was estimated based on previous literature (41, 42, 44).

Figure 7

Aggregate costs of dog rabies control (2017–2030) under four hypothetical scenarios: decrease in the price of dog rabies vaccine (including syringes and needles), increases in daily vaccination capacity of health workers, and effective dog population management and control. Notes: the four hypothetical scenarios assuming that a new technology impacted the feasibility of dog vaccination, reasonably improving current practices. The distribution of aggregate costs components was estimated based on previous literature (41, 42, 44).

Figure 8

Rabies elimination rank scores by rabies clusters. Notes: elimination rank scores were estimated for each rabies cluster (4) based on six criteria: proportion of the cluster considered rabies free, funding gap for elimination, dog vaccination coverage for 2015 estimates, gap in vaccination workforce, average years to achieve elimination, and average human development index. Rank scores ranged from 16 to 84. A low rank score represents a theoretically quicker pathway toward elimination.