rabies variant

Rabies is caused by a single virus, but that virus does not circulate as one undifferentiated pool. It exists as a set of genetically distinct lineages, usually called variants, and each one is kept going by a particular group of animals. The World Organisation for Animal Health, the intergovernmental body that sets animal health standards, describes rabies virus variants circulating in carnivores, most commonly domestic dogs and cats, and, depending on the continent, in other carnivores such as foxes and jackals or in bats.

That structure is why elimination targets are worded the way they are. Dogs are the main reservoir worldwide, the animal population that keeps the virus going, and most human deaths begin with a dog bite, so the global effort concentrates on the dog-maintained variant: vaccinate enough dogs, for long enough, and that lineage stops being passed on. Clearing it does not clear the others. A country can end human rabies from dogs and still have the virus circulating in its wildlife, which is why a validated elimination is always stated as elimination of dog-transmitted rabies rather than of rabies itself, and why surveillance in animals carries on afterwards.