Oral vaccination with microencapsuled strain 19 vaccine confers enhanced protection against Brucella abortus strain 2308 challenge in red deer (Cervus elaphus elaphus).
Bison (Bison bison) and elk (Cervus elaphus nelsoni) in the Greater Yellowstone Area (GYA), USA, are infected with Brucella abortus, the causative agent of bovine brucellosis, and they serve as a wildlife reservoir for the disease. Bovine brucellosis recently has been transmitted from infected elk to cattle in Montana, Wyoming, and Idaho and has resulted in their loss of brucellosis-free status. An efficacious Brucella vaccine with a delivery system suitable for wildlife would be a valuable tool in a disease prevention and control program. We evaluated Strain 19 (S19) in a sustained release vehicle consisting of alginate microspheres containing live vaccine. In a challenge study using red deer (Cervus elaphus elaphus) as a model for elk, alginate, a naturally occurring polymer combined with a protein of Fasciola hepatica vitelline protein B was used to microencapsulate S19. Red deer were orally or subcutaneously immunized with 1.5 x 10(10) colony-forming units (CFUs) using microencapsulated S19. Humoral and cellular profiles were analyzed bimonthly throughout the study. The vaccinated red deer and nonvaccinated controls were challenged 1 yr postimmunization conjunctivally with 1 x 10(9) CFUs of B. abortus strain 2308. Red deer vaccinated with oral microencapsulated S19 had a statistically significant lower bacterial tissue load compared with controls. These data indicate for the first time that protection against Brucella-challenge can be achieved by combining a commonly used vaccine with a novel oral delivery system such as alginate-vitelline protein B microencapsulation. This system is a potential improvement for efficacious Brucella-vaccine delivery to wildlife in the GYA.
Arenas-Gamboa
Angela M
AM
Department of Veterinary Pathobiology, Texas A&M University and Texas Agricultural Experiment Station, College Station, Texas 77845-1114, USA. aarenas@cvm.tamu.edu
Ficht
Thomas A
TA
Davis
Donald S
DS
Elzer
Philip H
PH
Kahl-McDonagh
Melissa
M
Wong-Gonzalez
Alfredo
A
Rice-Ficht
Allison C
AC
D000284:Administration, Oral; D000818:Animals; D000829:Animals, Domestic; D000835:Animals, Wild; D001428:Bacterial Vaccines / Q000008:administration & dosage*; D002003:Brucella abortus / Q000276:immunology*; D002006:Brucellosis / Q000517:prevention & control / Q000635:transmission / Q000662:veterinary*; D015169:Colony Count, Microbial; D003670:Deer; D004197:Disease Reservoirs / Q000382:microbiology / Q000662:veterinary; D004339:Drug Compounding / Q000662:veterinary; D005260:Female; D011897:Random Allocation; D013045:Species Specificity
D001428:Bacterial Vaccines