the epidemiology of animal rabies and public health implications

The Epidemiology of Animal Rabies and The Epidemiology of Animal Rabies and Public Health ImplicationsPublic Health Implications

Dr Paul Bartlett MPH., DVM., Ph. D.Dr Paul Bartlett MPH., DVM., Ph. D.VM 544 Veterinary Preventive VM 544 Veterinary Preventive

MedicineMedicine

Raccoon RabiesRaccoon Rabies

Raccoon rabies is moving our way!Raccoon rabies is moving our way! If it has been moving at 25 to 40 miles a year If it has been moving at 25 to 40 miles a year

despite our efforts to stop it.despite our efforts to stop it.– Initially slower movement to the west but not Initially slower movement to the west but not

anymore. anymore. – Movement can be aided by people:Movement can be aided by people:

» 350 mile jump to the Mid-Atlantic states.350 mile jump to the Mid-Atlantic states.» Jumped across Massachusetts in a garbage truck. Jumped across Massachusetts in a garbage truck.

Raccoon Rabies Raccoon Rabies Michigan and the Midwest in general has a very Michigan and the Midwest in general has a very

high raccoon population which could definitely high raccoon population which could definitely support a raccoon rabies epidemic.support a raccoon rabies epidemic.

Michigan’s options…Michigan’s options…– Hope?Hope?– River? (no)River? (no)– Control in Ohio?Control in Ohio?

» No, it broke through the immune barrier No, it broke through the immune barrier in 1999in 1999

– Control in Michigan?Control in Michigan?» DoughtfulDoughtful

Wildlife Rabies Vaccination BackgroundWildlife Rabies Vaccination Background In Ontario for foxes they used a trap, vaccinate and release In Ontario for foxes they used a trap, vaccinate and release

program. Other vaccines. Chicken heads!program. Other vaccines. Chicken heads! Now Canada and Europe have both used V-RG.Now Canada and Europe have both used V-RG. Vaccinia-rabies glycoprotien (V-RG)Vaccinia-rabies glycoprotien (V-RG)

– A product of molecular engineering.A product of molecular engineering.» Only one gene from the rabies virus spliced into the vaccina Only one gene from the rabies virus spliced into the vaccina

virus (small pox virus).virus (small pox virus).– Effective for fox, raccoons, dogs, and coyotes.Effective for fox, raccoons, dogs, and coyotes.– Several million tested in the USA and Europe.Several million tested in the USA and Europe.– No adverse effects on target or non-target animals.No adverse effects on target or non-target animals.– No public health problem if humans are exposed.No public health problem if humans are exposed.– Licensed for use by governments in the US.Licensed for use by governments in the US.

Wildlife Rabies Vaccination BackgroundWildlife Rabies Vaccination Background

Oral vaccination and related cost effectiveness:Oral vaccination and related cost effectiveness:– Swiss vaccinated their fox population - say “yes”.Swiss vaccinated their fox population - say “yes”.

» Due to the increased costs associated with a Due to the increased costs associated with a rabies epidemic in fox population.rabies epidemic in fox population.

» Increased costs associated with a rabies Increased costs associated with a rabies epidemic include animal diagnostic costs, epidemic include animal diagnostic costs, human treatments, health department human treatments, health department consultations, education, increased consultations, education, increased vaccinations for domestic pets, quarantine of vaccinations for domestic pets, quarantine of exposed animals, and the economic impact on exposed animals, and the economic impact on hunting and tourism. hunting and tourism.


The state of New Jersey - created an The state of New Jersey - created an immune barrier at Cape May in front of the immune barrier at Cape May in front of the advancing epidemic.advancing epidemic.– It worked for a while! Then budget cuts.It worked for a while! Then budget cuts.


The state of Massachusetts created an The state of Massachusetts created an immune barrier at Cape Cod. It distributed immune barrier at Cape Cod. It distributed baits in many ways at differing densities. baits in many ways at differing densities.


Ontario has a long history with V-RG and Ontario has a long history with V-RG and plans to continue to use it to keep raccoon plans to continue to use it to keep raccoon rabies at bay.rabies at bay.

Arguments for controlArguments for control Possible in theory.Possible in theory.

– Hawaii, and AustraliaHawaii, and Australia Threat to livestock, and Threat to livestock, and

public healthpublic health– No people have contracted No people have contracted

raccoon rabies strain.raccoon rabies strain. MI: Can protect 15sq. MI: Can protect 15sq.

mile in the barrier for mile in the barrier for every sq. mi. vaccinated.every sq. mi. vaccinated.

Environmentally friendly Environmentally friendly and humane.and humane.

Biologic threats:Biologic threats:– Movement by people and Movement by people and

animalsanimals Administrative threats:Administrative threats:

– Consistent effort needed Consistent effort needed every year, legislative every year, legislative support, tax on private land, support, tax on private land, interstate movement of interstate movement of raccoons, rehabilitors, law raccoons, rehabilitors, law enforcement priority, and enforcement priority, and prosecutor priority.prosecutor priority.

““Let nature alone”Let nature alone”

Arguments Against Control

•New DNR policy on raccoon relocation:•MVMA, Mich, Humane Soc., Rabies Working Group argued for no rehabilitation.

•DNR has decided upon only release in “country of origin.”

What about oral rabies vaccine in Michigan?

Immune barrier to protect 15 sq. mi. for every 1 in the barrier.

What if there is an outbreak behind the barrier?

Ring vaccination

Rabies in Domestic Anim als, 1955-2000

Rabies in Dom estic Anim als by M onth, 2000Cats Cattle Dogs

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the epidemiology of animal rabies and public health implications

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