By Hiral Anil Shah & Syed Shahid Abbas
The Global Alliance for Rabies Control (GARC) has set a target for worldwide rabies elimination by 2030. To achieve this there is a need for policy-makers to commit to cost-effective canine rabies control programmes at the population level.
Rabies is an infectious disease, largely transmitted to humans by bit
es from infected dogs, and can prove fatal without prompt treatment. Mass canine vaccination campaigns are the currently recommended rabies control strategy and have been successful inmany contexts. However, in many low- and middle-income countries, where there is an abundance of stray dogs, mass canine vaccination campaigns are often viewed as too costly or insufficiently effective. Combining canine vaccination with animal birth control (ABC) programmes is an alternative strategy which supports a socially stable but declining dog population. However, there is currently no evidence to show that combined programmes are a cost-effective intervention for rabies control.
Approximately 35% of all human rabies deaths occur in India. In Tamil Nadu state around 4.7 million cases of dog bite injuries and 350 suspected human rabies cases have been reported in the past five years. In order to address the problem of rabies and dog bites, the government currently provides free post-exposure prophylactic vaccination following a dog bite. Additionally, the government and NGOs have conducted localised, city-based, pilot canine vaccination and ABC programmes to reduce canine rabies transmission. However, these efforts are yet to be scaled-up to the district or state level due to policy concerns surrounding feasibility and financial sustainability.
Supported by a Grand Challenge award for developing One Health metrics, we used the programme and epidemiologic data from Tamil Nadu to populate an integrated dynamic transition and economic model. This model was used to assess and compare the costs and human health outcomes, such as death and dog bite burden, of several canine-based interventions including canine vaccination; canine vaccination with sterilisation in all dogs (the currently preferred procedure); and canine vaccination in all dogs with sterilisation in female dogs only. TheAnimal Welfare Board of India recommends a female-orientated ABC programme, as sterilizing predominantly female dogs should be sufficient to control the population.
We found that a relatively moderate strategy that combined mass canine vaccination with female sterilisation could cost-effectively reduce the incidence of human rabies. Sterilising 10% of female dogs, alongside the recommended mass canine vaccination programme, could reduce rabies deaths and dog bite morbidity by over 90% within five years. Likewise, combining canine vaccination with the sterilisation of around a quarter of female dogs annually could prevent 4,000 dog bites per year.
Our results suggest that combining mass vaccination with female dog sterilization has the potential to cost-effectively and dramatically reduce human rabies mortality. However, coordination between different sectors of state government will be fundamental to the intervention’s success.
Hiral Anil Shah is a Health Economics Consultant to the Public Health Foundation of India.
Syed Abbas is a public health researcher affiliated with Health & Nutrition cluster at the Institute of Development Studies, UK and the Public Health Foundation of India.
Our study was funded by a grant from the Bill & Melinda Gates Foundation through the Grand Challenges Exploration Initiative. It was conducted in collaboration with researchers from Center for Infectious Disease Modeling and Analysis at Yale and the London School of Hygiene & Tropical Medicine.