Tick bite paralysis is an uncommon illness in dogs. The condition occurs after a tick bites and attaches to a dog, begins to engorge with blood and finally secretes a toxin. This toxin, which is not fully understood, blocks the nerve function to the muscles resulting in profound weakness. The illness is caused by a neurotoxin produced in the tick's salivary gland which prohibits blood clotting. So far, the toxin has been associated with female ticks in the eastern wood tick family, western mountain tick family and Australian tick family.
Symptoms usually begin to appear around 6-9 days after a tick has attached to the skin of the dog. This disease is somewhat seasonal and more prevalent in the summer time in areas where the seasonal temperatures are more consistently warm.
Symptoms of tick paralysis are gradual in nature, including:
High blood pressure
Fast heart rate and rhythm (tachyarrhythmias)
Weakness, especially in the hind limbs
Partial loss of muscle movements (paresis)
Complete loss of muscle movement (paralysis), commonly seen in advanced disease state
Poor reflexes to complete loss of reflex
Low muscle tone (hypotonia)
Difficulty in eating
Disorder of voice (dysphonia)
Asphyxia due to respiratory muscle paralysis in severely affected animals
Excessive drooling (sialosis)
Megaesophagus (enlarged esophagus)
Excessive dilatation of pupil in the eye (mydriasis)