Eliminating rabies at its source in Asia and Africa
At the beginning of May, at the World Small Animal Congress in Birmingham (UK), Dr Tiziana Lembo of the University of Glasgow, and GARC, presented evidence to support the vaccination of domestic dogs as the best way to prevent rabies worldwide.
Most people affected by rabies live in Asia and Africa and are already contending with extreme poverty. Whilst tackling the disease through post-exposure prophylaxsis is the common approach, this is expensive, supply is often erratic, and the victim still has to contend with the emotional and physical scars of an attack by a rabid animal.
Examination of the transmission path shows that domestic dogs are overwhelmingly the source of rabies in people, and even in other species. Vaccination of a big enough proportion of domestic dogs breaks the chain of transmission, eventually enabling disease elimination. That ‘big enough’ proportion is 70%, a figure based on the number of subsequent transmissions each infected dog causes, and the size and turnover of domestic dog population.
The cost of vaccinating a dog is about $2 per animal. Prevention by vaccination of 70% of a domestic dog population requires high initial investment but in the long term is much more cost-effective than the current strategy.
Research from around the world shows that most dogs, even those which are free-roaming, have owners and that those owners (irrespective of socio-economic status) are willing to walk considerable distances to have their animals vaccinated. For very remote communities, home visits have proved effective.
Knowing how many dogs there are remains an operational constraint. Currently estimates are based on extrapolation of research but encouraging governments to include information about dogs on nationwide censuses of human populations would help.
Mobile phone technology is expanding in developing countries and making things easier. Improved communication helps with vaccine stock management, and reporting incidence of the disease and the impact of control measures.
Education and participation at the community level is crucial. The approaches used to engage local communities are well received and attendance at vaccination clinics is good. World Rabies Day (a GARC initiative), held annually since 2008, now has participation from 150 countries.
At the national level, some countries have encouraged engagement between veterinary and medical services. The administrative challenges of this can be difficult but efforts should focus on increasing capacity in these services for rabies surveillance and prevention, and integrating budgets across relevant ministries.
To date, global efforts to eliminate rabies have relied heavily on advocates like GARC and the Partners for Rabies Prevention. Their job has included assessing the global burden of rabies; raising awareness of the disease at all levels; identifying and addressing gaps in canine rabies prevention, control and elimination; helping endemic countries to design national programmes to tackle their own situation; and securing financial support.
Dr. Lembo concluded by saying that eliminating rabies at its source in Asia and Africa is an achievable goal and we should continue to work towards it. However, because rabies mostly affects poor, marginalised communities with little political voice, we still need to improve awareness and make sure that research findings are translated into policy.
A report of Dr Lembo's talk was published in the Veterinary Record in April 2012 (Vol 170, issue 16) and an extract can been read here.