Daboia (Vipera) palaestinae envenomation in horses: Clinical and hematological signs, risk factors for mortality and construction of a novel severity scoring system.

The paper explores the effects of Daboia palaestinae snake venom on horses in Israel and introduces a new system to predict the severity of the snakebite’s impact. The research identifies common symptoms in affected horses and significant risk factors that lead to increased mortality.

Study Overview and Findings

• The research involves a comprehensive survey which recorded the symptoms and blood sample results of 123 horses over a four-year period that have been bitten by the Daboia palaestinae snake.
• The most common symptoms include local swelling, elevated heart rate, increased respiratory, visible bite marks and decreased appetite.
• Abnormalities in the blood include increased white blood cells count, higher neutrophils level, increased creatine phosphokinase, decreased total protein level, decrease in total carbon dioxide, and hyperphosphatemia.

Mortality Rate and Risk Factors

• The research calculated a 20.3% fatality rate out of the 123 horses studied.
• Certain risk factors appeared to increase the likelihood of death. These include horses weighing under 200kg, horses bitten in the hind limb, severe local swelling, altered mental status, increased respiratory efforts, bleeding disorders, dehydration, basophilia, monocytosis, elevated bilirubin levels, decreased calcium levels, and hyperphosphatemia.

Snakebite Severity Scale (SSS)

• The data gathered from these risk factors was used to create a Snakebite Severity Scale (SSS) designed for horse bites in the field which includes seven dichotomous parameters.
• This tool demonstrated an ability to predict mortality with a sensitivity of 95% and a specificity of 68% with a cut-off value of 1.5 set as the cut-off for detecting potential fatalities.
• This prognostic tool can provide invaluable assistance to veterinarians when treating snakebite cases. It also aids in effective communication with the owners about the possible outcomes and severity of their horse’s condition.

Significance of the Study

• This is an important study as it fills gaps in the understanding around D. palaestinae envenomation in horses, a topic with scant documentation despite the snake’s prevalence in Israel and the fact that horses are used to produce antivenom.
• It also provides a practical tool (SSS) that can be used directly in the field, increasing the potential for timely and effective interventions in snakebite cases and thus potentially reducing the fatality rate.