Deaths from rabies: Lessons from Kenya

WHEN a person hears about rabies, it’s often not thought of as an immediate personal threat. But rabies kills about 60 000 people every year — the majority of deaths are in Africa and Asia. Rabies is a viral disease transmitted to humans through bites from rabid animals. The virus infects the central nervous system ending in the brain, at which point death is inevitable.

This year several major international organisations have, for the second year in a row, endorsed the global goal of elimination of human deaths from dog rabies by 2030. It also marks three years since Kenya launched a strategic plan that would progressively reduce human deaths due to dog rabies to make the country rabies free by 2030.

For Kenya, the focus on rabies was informed by results of an exercise that mapped diseases in the country. It placed rabies as one of top five animal diseases that affect people in the country. Rabies is estimated to kill 2 000 people every year in Kenya.

I was involved in drafting Kenya’s strategy for the elimination of dog-mediated human rabies. I have also been actively involved in its implementation in pilot areas. The strategy is quite straight forward: vaccinate 70 percent of dogs annually (the level needed to break the dogdog transmission cycle), provide prompt post-exposure vaccines to people bitten by suspected rabid dogs, and execute a public education and awareness campaign.

Vaccinating dogs

Effective vaccines against dog rabies are available in Kenya. But there are several challenges associated with vaccinating dogs.

The first important metric is determining the size of the dog population in the country. Data doesn’t exist. The country did a livestock census as part of a population census in 2009, dogs were left out. The country now has the opportunity to capture the data during the 2019 population census.

We use cross-sectional household surveys to determine the human: dog ratio which allows us in turn to estimate the dog population. On average, across most of Africa the human: dog ratio estimate is 8:1 in rural areas and higher in urban areas. Kenya, which has a population of 48 million people, is estimated to have a dog population of 6 million. To meet the 70 percent target, this means that 4,2 million dogs needed to be vaccinated consistently to achieve rabies elimination.

Our experience in the pilot areas shows that there are two critical elements to success: the first is that people need to buy into the effort, and secondly that local government needs to provide resources to vaccinate the dogs and provide post-exposure treatment.

Makueni County, where elimination activities started, has put in its own resources and organised vaccination campaigns that reaches 60 percent of its dog population.

What we have learnt is that dog owners will bring in their adult animals, but likely to leave puppies behind. We also learnt that successful campaigns require innovations such as mapping vaccination points as well as rapid analysis of data to avoid leaving geographical pockets of unvaccinated dogs because if they are large enough they allow the virus to continue circulating.

Recent reports suggesting that rabies vaccines remains viable after exposure to elevated temperature, presents opportunities to lower the cost of delivery and reach dogs in remote areas, where maintaining the cold chain is challenging.

Human vaccines

Bite from victims infectionfrom rabidif they dogs get are post-exposureprotected vaccines promptly. For a disease that poorly competes with other health priorities such as malaria, the availability of rabies vaccines as well as their high cost increases the risk of rabies deaths.

In Kenya, we find that in the absence of surveillance data that reports the number of people bitten, the number of rabies positive dogs, or confirmed human deaths due to rabies, the health care system will rarely prioritise provision of these life-saving vaccines. — Conversation Africa.