What is tick paralysis?
Tick paralysis is a life-threatening disease involving the progressive paralysis of muscles in the body. In Australia, it is caused by the adult female paralysis tick, Ixodes holocyclus. Over 95% of all tick bites in Eastern Australia are caused by this species of tick. What most people refer to as bush, grass, or seed ticks are in fact the younger life forms (nymph or larva) of the paralysis tick.
When a paralysis tick attaches to an animal and begins to feed a neurotoxin is injected from the tick’s salivary glands into the animal. The toxin causes clinical signs of paralysis within 48 hours and can rapidly lead to respiratory failure and death. Dogs and cats can be very sensitive to the tick toxin, with only one paralysis tick required to cause potentially fatal paralysis. Other animals, such as birds, rabbits, and native species, are more resistant and require larger numbers of ticks before they are affected. Individual animals can sometimes also develop a degree of natural resistance to tick paralysis.
What are the signs of tick paralysis?
Tick paralysis signs can depend slightly on the location of the tick, but generally start as weakness or wobbliness in the back legs. Other early signs include a change in the sound of the bark or meow, grunting, wheezy or laboured breathing, vomiting, and lethargy, as some animals hide the weakness in their back legs by sitting down and resting. If the paralysis tick is located near the eyes the eyelids can become paralysed, leading to an inability to blink. As paralysis progresses your pet will also lose the ability to swallow effectively and the ability to urinate. The paralysis of the airways and breathing muscles are what makes tick paralysis so rapidly fatal.
What should I do if I suspect my pet has tick paralysis?
If you find a paralysis tick attached to your pet, you should remove it immediately, keep the tick for reference, and call us for further advice. The easiest way to remove a tick is to use a tick twister device or your fingernails to grip the tick close to the head where it attaches to the skin, twist the tick, and pull it out. Do not worry if the tick head remains, as it will fall out itself after the tick dies. If you are unsure how best to remove the tick, please keep your pet calm and bring them straight to us and we will remove the tick for you.
If your pet is not showing any signs of tick paralysis treatment is not required, though you should keep your pet as calm and stress-free as possible for 48 hours following tick removal. However, as soon as signs begin to develop it is important to seek veterinary treatment immediately as your pet’s condition may rapidly deteriorate, even after the tick has been removed.
Please note that removing ticks from animals is different from removing ticks from humans. Creams and sprays used to remove ticks from humans should not be used in animals. For information on how to remove paralysis ticks in humans, contact your health care professional.
How can tick paralysis be prevented?
We recommend year-round tick preventatives be used in all dogs and cats, as paralysis ticks are so common in our area. There are many good products available now, including oral chews for dogs such as Bravecto and Simparica, top-spots for dogs such as Bravecto (though we recommend this be applied every 3-4 months rather than every 6 months), top-spots such as Bravecto and Revolution Plus in cats, and tick collars for both species, such as Seresto. No preventative is 100% effective though so we recommend daily tick checks of your pet, best conducted by ‘walking’ your fingers through their coat in a systematic manner, concentrating on the chest and head, as this is where most ticks are found. Clipping your pet’s fur short during the warmer months also greatly assists in finding paralysis ticks.
Dr Caroline Wood