Efficacy of oral vaccination in the final stage of fox rabies elimination in Switzerland.
Subsequent to rabies vaccination campaigns, two well-established methods for the determination of the proportion of vaccinated foxes--the detection of tetracycline (TC) in bones and the detection of virus neutralizing antibodies (VNA) in thoracic fluids--were used and compared. Special emphasis was given to the effect of a new method of bait distribution at the den, which is primarily targeted at young foxes. The overall proportion of vaccinated animals estimated by TC was 60% as compared to 50% by VNA. In young foxes overall, significantly lower proportions of vaccinated animals (58% by TC and 40% by VNA) than in adult foxes (75 and 59%) were estimated with both methods. Low proportions of vaccinated young animals were found after spring (39 and 18%), but also after autumn vaccination (56 and 35%). In contrast, after den vaccination the level of vaccination of young foxes reached that of adult foxes. The theoretical implication of the successful elimination of fox rabies in Switzerland in spite of a relatively low overall proportion of VNA-positive animals is discussed.
Bugnon
P
P
Institute of Cell Biology, Swiss Federal Institute of Technology, Zürich, Switzerland.
Breitenmoser
U
U
Peterhans
E
E
Zanoni
R
R
D000284:Administration, Oral; D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis; D004196:Disease Outbreaks / Q000517:prevention & control / Q000662:veterinary; D005589:Foxes; D011818:Rabies / Q000453:epidemiology* / Q000517:prevention & control*; D011819:Rabies Vaccines / Q000008:administration & dosage*; D011820:Rabies virus / Q000276:immunology*; D013557:Switzerland / Q000453:epidemiology; D014611:Vaccination / Q000662:veterinary*
D000914:Antibodies, Viral; D011819:Rabies Vaccines