Risk factors associated with the occurrence of undesired effects in sheep and goats after field vaccination with modified-live vaccine against bluetongue virus serotypes 2, 4 and 16

• Published in: Veterinary microbiology 2010-11, Vol.146 (1-2), p.44-50
• Main Authors: Savini, G., Cannas, A., Casaccia, C., Di Gialleonardo, L., Leone, A., Patta, C., Nicolussi, P.
• Format: Article
• Language: English
• Subjects: adverse effects; animal pathogens; Animals; Antibodies, Neutralizing - immunology; Antibodies, Viral - immunology; Applied microbiology; Biological and medical sciences; bluetongue; Bluetongue - immunology; Bluetongue - prevention & control; Bluetongue - virology; Bluetongue virus; Bluetongue virus - immunology; dairy animals; diseases and disorders (animals and humans); environmental factors; Fundamental and applied biological sciences. Psychology; Goats; Goats - immunology; Goats - virology; hematology; live vaccines; maedi-visna disease; Maedi-visna virus; Microbiology; milk yield; Miscellaneous; Modified-live vaccine; Reverse Transcriptase Polymerase Chain Reaction - veterinary; Risk Factors; serotypes; Sheep; Sheep - immunology; Sheep - virology; Side effects; signs and symptoms (animals and humans); vaccination; Vaccination - adverse effects; Vaccination - veterinary; Vaccines, antisera, therapeutical immunoglobulins and monoclonal antibodies (general aspects); Vaccines, Attenuated - adverse effects; Vaccines, Attenuated - immunology; Vaccines, Attenuated - pharmacology; Viral Vaccines - adverse effects; Viral Vaccines - immunology; Viral Vaccines - pharmacology; viremia; Virology; Visna maedi virus
• ISSN: 0378-1135; 1873-2542
• DOI: 10.1016/j.vetmic.2010.04.020

In the 2004, the Sardinian bluetongue (BT) vaccination campaign used the combination of monovalent BTV-2, BTV-4 and BTV-16 modified-live vaccines manufactured by the Onderstepoort Biological Products in South Africa. Following vaccination, some herds showed temperature, oedema, lameness, hyperaemia and decrease in milk production, and some others remained perfectly healthy. This study aimed to evaluate whether important factors present in the herd at the time of vaccination could be associated to the occurrence of undesired effects observed after immunisation with BTV modified-live vaccines. A sample of 17 sheep and 4 goat flocks, for a total of 670 animals, were included in the study and risk factors such as presence of most important parasitic, bacterial and viral diseases as well as anomalies of biochemical and haematological parameters were associated to the presence or absence of side effects. For each factor the relative risk and 95% confidence interval were calculated. Following vaccination, bluetongue-like symptoms were observed in 13 flocks. In these flocks, a higher (P