Tetanus in the equine species: a retrospective study of 31 cases.

BACKGROUND: Few studies exist about factors affecting the outcome of horses with tetanus. ANIMALS: 31 equids (30 horses and 1 donkey) with a clinical diagnosis of tetanus admitted to the Equine Clinic of the University of Liege between 1991 and 2006. The cases were divided into two groups according to the outcome (survivors and non-survivors). METHODS: The clinical data of survivors and non-survivors were compared using an ANOVA (continuous data) or a Fisher's test (discrete data). RESULTS: The survival rate was 32%. Most animals were 5 years or younger, and none had been appropriately vaccinated. The non-survivors were significantly younger than the survivors. The development of dyspnoea, recumbency, and the combination of dysphagia, dyspnoea, and recumbency was observed significantly more in the non-survivors than in the survivors. The timing of tetanus antitoxin administration (either immediately after the onset of suggestive signs or after a delay) was not different between the two groups. The time between the occurrence of a wound and the first signs ranged from 2 days to 2 months and was not significantly different between groups. All non-survivors died within 8 days of the first signs. CONCLUSIONS & CLINICAL IMPORTANCE: This study suggests that young animals are affected more often and more severely by tetanus than older animals. Dyspnoea, recumbency, and the combination of dysphagia, dyspnoea, and recumbency can be considered as indicators of a poor prognosis in equids suffering from tetanus.