DISTRIBUTION
OF THE RABIES VIRUS IN WESTERN CANADA
Although, much
emphasis is put
on the
carnivore population, the virus is also present in other reservoir
species. These wild animals carry the virus among their
population, allowing it to persist and spread in the environment.
It has been found in the arctic fox, the red fox, the striped
skunk and
many bat
species across North-America. It's also
found in the pet population and this is the reason for routine rabies
vaccination and it may even spill over into livestock
and
sometimes in humans.
In British
Columbia,
insect eating bats are the only rabies carriers, (7)
although
there have been sporadic cases occurring in other species. Since 1960,
all
positive cases of rabies were found in bats and occasionally in a small
number
of terrestrial mammals. Remarkably, there have been no cases reported
in
domestic dogs or wild carnivores or any species. (6)
In Alberta for example the rabies virus is found in two main
reservoirs: the
striped skunk and in various species of bats, though little brown bats (Myotis lucifugus) are the most common
bat species in Alberta. Cases in skunks tend to be along the Saskatchewan
border and the Montana border. Cases of rabies in bats, although they are found
throughout
the province are concentrated near human populations. The Albertan
government
has taken steps to prevent the spread of the virus among the skunk
population
and thus limiting the risk of spread to other species.
Any skunk found dead or to be acting in a
bizarre manner is submitted for testing at the laboratory in Lethbridge. If
the skunk is found to be rabid, other
skunks 8 kilometres round where the original skunk was found are
collected and
brought in for testing. The few skunks
testing positive are thought to be from enzootic areas. (8)
In Saskatchewan, the rabies virus is found
predominantly in the skunk
population
and also in bats. There also have been cases of rabies seen in other
wild
animals and in livestock and pets. The occurrence of rabies in the
skunk
population fluctuates - when it is high there is
also an
increased occurrence of rabies in wild and domestic animals, increasing
the risk
to humans. (10)
In Manitoba, skunks,
foxes and bats
are the main carriers of rabies. Due to favourable conditions, the
virus has
increased significantly among the skunk population.
