Submitted to: American Journal of Veterinary Research
Publication Type: Other
Publication Acceptance Date: May 18, 2012
Publication Date: July 1, 2012
Citation: Alt, D.P., Olsen, S.C., Bolin, C. 2012. Letters to the Editor. American Journal of Veterinary Research. 73(7):928-929. Technical Abstract: We would like to express several concerns regarding the article “Efficacy of vaccination of cattle with the Leptospira interrogans serovar Hardjo type hardjoprajitno component of a pentavalent Leptospira bacterin against experimental challenge with Leptospira borgpetersenii serovar Hardjo type hardjo-bovis” by Rinehart et al. In this study, the authors evaluated the efficacy of the Leptospira interrogans serovar Hardjo type hardjoprajitno component of a commercial pentavalent-adjuvanted combination vaccine against challenge with Leptospira borgpetersenii serovar Hardjo type hardjobovis. Efficacy was determined on the basis of reduction of renal infection and urinary shedding of the challenge strain. While the results of the study are interesting, and the author’s mention potential reasons for differences in their results compared to prior studies involving multivalent bacterins containing L. interrogans serovar Hardjo type hardjoprajitno, we believe conclusions derived from the results may leave readers at risk of misinterpretation. Although the presented data is of interest to veterinarians and scientists working in leptospirosis, we are concerned that procedures used in this study may not have been sufficiently rigorous to evaluate vaccine efficacy. In particular, data from other studies would suggest that strictly relying on culture of leptospira organisms from blood or urine for assessment of vaccine efficacy is not optimal.