1. FACTORS INFLUENCING THE ANTIBODY RESPONSE TO RABIES VACCINATION
V.Jakel1
K.Cussler2, M.König1, H.-J.Thiel1
1Institute of Virology, Justus-Liebig-Universität Giessen, Germany
2Paul-Ehrlich-Institut, Langen, Germany
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2. Introduction
Dogs and cats vaccinated against rabies according to recommendations of manufacturer may fail to reach the titre of 0,5 IU/ml required for travel purposes
Cliquet, 2003: 7,4% dogs 1,9% cats
Mansfield, 2004: 5,2% dogs 2,7% cats (lab 1)
4,1% dogs 2,9% cats (lab 2)
Survey Paul-Ehrlich-Institut, 2004:
10-18% dogs 0-5% cats (lab 1 – 3)
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3. Material and Methods Sera tested by FAVN assay
Questionnaire sent to veterinarians of dogs and cats tested for travel purposes
Separate data query for animals with test result < 0,5 IU/ml („test failed“) and ≥ 0,5 IU/ml („test passed“)
< 0,5 IU/ml
≥ 0,5 IU/ml ∑
Dogs
1375
489
1864
Cats 19 74 93
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4. Influences on test result I: previous vaccinations
Primovaccinated dogs have a 6-fold higher risk for test failure than multivaccinated dogs.
dogs
cats
OR 6.52, p<0.0001, 95%-CI: 4.9 – 8.7
OR 8.49, p=0.0019, 95%-CI: 2.2 – 32.8
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5. Influences on test result II (dogs): time vaccination - blood sampling
Primovaccinated dogs tested more than 120 days after vaccination have a 3,27 fold higher risk for test failure than dogs tested during the first four months after vaccination
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6. Travel destinations (all animals)
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7. Influences on test result III (dogs): Vaccine
4 different rabies virus strains for inactivated vaccines in use in Germany
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8. Influences on test result III (dogs): Vaccine
Dogs vaccinated with vaccine strains 2 or 3 have a lower risk for test failure than dogs vaccinated with vaccine strain 1 or 4
Vaccine strain OR
95%-CI
P*-value 1 2
3.923
2.519
6.110
<0.0001 3
3.311
2.042
5.369 4
2.230
1.750
2.841
1.882
1.380
2.565
1.761
1.125
2.755
0.0134
1.185
0.875
1.604
0.2725
*αi Bonferroni-Holm adjusted for multiple tests
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9. Influences on test result IV (dogs): Vaccine
Dogs vaccinated with monovalent vaccines have a lower risk for test failure (OR 0.662, 95%-CI: , p=0.0007)
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10. Summary Significant influence on test outcome:
Number of rabies vaccinations animal has received in lifetime
Time between vaccination and blood sampling
Strain of rabies vaccine
Vaccine formulation
No significant influence on test outcome:
Sex
Medical treatment in parallel to rabies vaccination
Travel regulations frequently not complied
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11. Overall compliance of regulations
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12. Conclusions
Booster vaccination necessary in dogs and young cats to enhance probability of test result of ≥ 0,5 IU/ml
Significant differences between vaccines to induce rabies virus neutralizing antibodies
Harmonization of regulations for better compliance compulsory
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13. Outlook
Additional statistical analysis of data on influence of vaccination history and vaccines
Influence of test virus strain (CVS) and vaccine strains on FAVN results
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14. Acknowledgements C. Förster M. Lenhard S. Deike B. Bank-Wolf
Institute of Virology
Justus-Liebig-University
Giessen
C. Förster
M. Lenhard
S. Deike
B. Bank-Wolf
Dr. D. Chauvet
PD Dr. A. Hoffmann
Dr. A. Mergel
Federal agency for sera and vaccines
The study was financially supported by the Federal Ministry of Food, Agriculture and Consumer Protection (BMVEL), Germany
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