Results of vaccination of Asian elephants (Elephas maximus) with monovalent inactivated rabies vaccine.
OBJECTIVE
To evaluate the humoral immune response of Asian elephants to a primary IM vaccination with either 1 or 2 doses of a commercially available inactivated rabies virus vaccine and evaluate the anamnestic response to a 1-dose booster vaccination.


METHODS
16 captive Asian elephants.


METHODS
Elephants with no known prior rabies vaccinations were assigned into 2 treatment groups of 8 elephants; 1 group received 1 dose of vaccine, and the other group received 2 doses of vaccine 9 days apart. All elephants received one or two 4-mL IM injections of a monovalent inactivated rabies virus vaccine. Blood was collected prior to vaccination (day 0) and on days 9, 35, 112, and 344. All elephants received 1 booster dose of vaccine on day 344, and a final blood sample was taken 40 days later (day 384). Serum was tested for rabies virus-neutralizing antibodies by use of the rapid fluorescent focus inhibition test.


RESULTS
All elephants were seronegative prior to vaccination. There were significant differences in the rabies geometric mean titers between the 2 elephant groups at days 35, 112, and 202. Both groups had a strong anamnestic response 40 days after the booster given at day 344.


CONCLUSIONS
Results confirmed the ability of Asian elephants to develop a humoral immune response after vaccination with a commercially available monovalent inactivated rabies virus vaccine and the feasibility of instituting a rabies virus vaccination program for elephants that are in frequent contact with humans. A 2-dose series of rabies virus vaccine should provide an adequate antibody response in elephants, and annual boosters should maintain the antibody response in this species.
Isaza
Ramiro
R
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610.
Davis
Rolan D
RD
Moore
Susan M
SM
Briggs
Deborah J
DJ
D000704:Analysis of Variance; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D000917:Antibody Formation / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004606:Elephants / Q000276:immunology*; D005260:Female; D008297:Male; D011818:Rabies / Q000517:prevention & control / Q000662:veterinary*; D011819:Rabies Vaccines / Q000494:pharmacology*; D014611:Vaccination / Q000662:veterinary*; D015164:Vaccines, Inactivated / Q000494:pharmacology
D000914:Antibodies, Viral; D011819:Rabies Vaccines; D015164:Vaccines, Inactivated