The danger posed by tetanus infection in horses has been highlighted in a retrospective study in Europe, with researchers identifying factors that point to the likelihood of survival or death.
Thirteen researchers across Europe were involved in the study, in which the records of 155 tetanus cases in adult equids and 21 in foals from western, northern, and central Europe were evaluated.
All cases had occurred between 2000–2014 and were handled across 20 university teaching hospitals and private referral centers.
Gaby van Galen and her colleagues, writing in the Journal of Veterinary Emergency and Critical Care, reported that around two-thirds of the adults and foals did not survive.
Among adults, there were 49 survivors and 85 non-survivors, for a mortality rate of 68.4 percent. Among the foals, 7 survived and 10 died, for a mortality rate of 66.7 percent.
The study team compared variables from the history and clinical examinations in each case and related those back to whether the animals survived. Cases euthanized for financial reasons were not included.
Variables associated with survival in adults included standing, normal intestinal sounds and defecation, voluntarily drinking, eating soft or normal food, lower heart and respiratory rates, high base excess on admission, and mild disease severity.
Variables associated with death included a lack or loss of appetite, difficulty in swallowing, shortness of breath, low blood potassium concentration on admission, moderate to severe disease grading, recumbency and seizures during hospitalization, and treatment with glycerol guaiacolate, intravenous fluids, and intravenous glucose solutions.
Factors associated with survival in foals included standing on admission, voluntarily eating soft food and drinking, older age, and longer hospitalization delay.
The study team found that outcomes were not different between different tetanus antitoxin (TAT) dosages, although there was a trend of increasing survival rate with increasing dosages. Further evaluation was warranted, they said.
Cases were rare in animals whose tetanus vaccination was up to date. In the four cases that did occur, outcomes were better and the animals had shorter hospital stays.
“Prognosis for equine tetanus is poor with similar outcome and prognostic factors in foals and adults,” the researchers concluded. “Several prognostic indicators relate to the ability to eat or drink, and more severe clinical signs relate to poor outcome.”
van Galen, G., Rijckaert, J., Mair, T., Amory, H., Armengou, L., Bezdekova, B., Durie, I., Findshøj Delany, R., Fouché, N., Haley, L., Hewetson, M., van den Hoven, R., Kendall, A., Malalana, F., Muller Cavalleri, J., Picavet, T., Roscher, K., Verwilghen, D., Westermann, C. and Saegerman, C. (2017), Retrospective evaluation of 155 adult equids and 21 foals with tetanus from Western, Northern, and Central Europe (2000–2014). Part 2: Prognostic assessment. Journal of Veterinary Emergency and Critical Care. doi:10.1111/vec.12669
The abstract can be read here.