Rabies Epidemiology in Raccoon dogs and foxes A
Rabies Epidemiology in Raccoon dogs and foxes A Singer K Kauhala K Holmala GC Smith
Raccoon dogs • invasive • high population density Why successful ? • omnivorous • large litters • hibernate (Photo: K. Kauhala)
Risk of persistent rabies in Finland Epidemiology is influenced by: • Two vectors relative density inner- and inter-specific transmission • Behavioural differences reproduction hibernation
Two vectors rabies disease model Fox – Healthy Reproduction Mortality Infection Fox – Infected Reproduction Mortality Incubate Fox – Rabid Rac dog – Healthy Reproduction Mortality Hibernation Infection Rac dog – Infected Reproduction Mortality Hibernation Incubate Rac dog – Rabid
Joint threshold density for rabies risk Threshold density for 70% risk in foxes Threshold density raccoon dogs Rabies risk below 70 %
Joint threshold density for rabies risk Population densities (Southern Finland) Rabies risk below 70 %
Scenarios for Vaccination Strategies Assessment of threshold 90% eradication success after 5 years Intended vaccination campaign • 3 years • spring and autumn vaccination • 50% susceptibles are vaccinated Complications • only foxes vaccinated • spring vaccination too early for hibernating raccoon dogs • no raccoon dog hibernation in warmer climates
Effects of vaccination - hibernation
Effects of vaccination - hibernation
Effects of vaccination - hibernation
Effects of vaccination - hibernation
Effects of vaccination - hibernation
Effects of vaccination – active in winter
Effects of vaccination – active in winter
Conclusion • Both vector species are relevant • Vaccination of foxes only is insufficient • Late vaccination in spring • Hibernation reduces risk of an outbreak Thank you for your attention !
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