Tick Paralysis in Dogs: Symptoms, Emergency Steps and Prevention

What is tick paralysis?

The Australian paralysis tick attaches to an animal and feeds on its blood. While feeding, the female produces a toxin that interferes with the signals travelling between nerves and muscles. As more toxin is injected, the affected animal becomes progressively weaker, usually starting at the back end and moving forward. Left untreated, it eventually affects the muscles involved in swallowing and breathing, which is what makes the condition dangerous rather than merely unpleasant.

Australian native animals such as possums and bandicoots carry these ticks with little effect and act as hosts, which is how ticks arrive in suburban backyards backing onto bush. Dogs and cats have no such tolerance.

Where and when do paralysis ticks occur in Australia?

Ixodes holocyclus is found along the eastern seaboard, broadly from north Queensland through New South Wales to northern Victoria, concentrated in a relatively narrow humid coastal band of wet forest, bushland and the suburbs that adjoin them.

Adult ticks are most common from spring through to mid summer, which is why October matters. In the northern part of the range ticks are found all year round, and any life stage can turn up in any month anywhere in the range, so the risk rises and falls rather than switching on and off. Activity increases with humidity and after rain, so a warm wet week is exactly when to be most vigilant.

Two things catch people out. The first is travel: a dog that lives well outside the tick zone can pick one up on a weekend away on the coast, and the owner is not looking for ticks because they do not live with them. The second is that you do not need to go bushwalking. A backyard that possums visit is enough.

What does a paralysis tick look like?

Before feeding, a paralysis tick is small, flat and easy to mistake for a scab, a skin tag or a grass seed. As it feeds it becomes engorged and swells, changing from a pale greyish colour to a fuller bluish grey, and at that point it is easier to see but the toxin has usually already been injected.

A tick has legs clustered towards the head end, which distinguishes it from a skin tag if you look closely. Where a tick has recently been attached and has dropped off, you may find what is often called a crater: a raised, reddened, sometimes scabby circular patch of skin. A crater matters, because it tells you a tick has been feeding even though there is nothing left to find.

There are other tick species in Australia, including brown dog ticks and bush ticks, which do not cause paralysis. Telling them apart is not something to attempt while a dog is unwell. If you find a tick and your dog has any signs at all, treat it as a paralysis tick until a vet says otherwise. If you can safely keep the removed tick in a sealed container, take it with you.

How long does it take for a tick to make a dog sick?

This is the most useful fact in the whole article, because it is what makes searching worthwhile.

The adult female does not usually inject detectable amounts of toxin until around the third day of attachment. The largest amounts go in around days five and six. That delay means a tick found and removed in the first day or two may never cause a problem at all, and it gives an owner who searches daily two or three separate chances to find a tick before it does damage.

It also explains something that confuses owners: signs can appear days after the outing where the tick was picked up. If your dog becomes wobbly on a Wednesday, the relevant walk may well have been the Saturday before.

Symptoms of tick paralysis in dogs, in the order they usually appear

Progression varies between dogs and can be faster in small dogs, but the sequence is fairly consistent.

Early signs

•    A change in the bark. It may sound softer, hoarse, or different in pitch. Owners often describe it as the dog sounding odd rather than sounding unwell.

•    Weakness or wobbliness in the back legs, a swaying gait, or reluctance to jump up.

•    Vomiting, retching, or repeated swallowing attempts.

•    Loss of appetite, or dropping food.

Progressing

•    Difficulty standing, or standing and then sinking back down.

•    Weakness moving forward into the front legs.

•    Excessive drooling or coughing, often related to difficulty swallowing.

•    Wide, staring pupils, or a change in how the dog blinks.

Advanced and immediately life threatening

•    Inability to stand or lift the head.

•    Laboured, noisy, grunting or unusually fast breathing.

•    Blue or grey gums.

•    Collapse.

The gap between the first sign and a dog in serious trouble can be a matter of hours. Waiting until the picture is unmistakable is the single most common reason outcomes are worse than they needed to be.

Cats get tick paralysis too

This article is about dogs because that is where most cases are seen, but cats are affected and can become critically ill, including indoor cats that get out occasionally. The early signs in a cat are similar: a change in the meow, wobbliness in the hind legs, vomiting or retching, and changed breathing.

There is one additional danger specific to cats. Some tick products registered for dogs contain permethrin, which is toxic to cats. Australian approved labels for permethrin containing dog spot-ons are required to warn owners to keep cats separated from recently treated dogs, because cats have been poisoned after grooming or contacting a dog treated 48 hours earlier. Never apply a dog product to a cat, and speak to your veterinarian about what is appropriate for a cat living in a paralysis tick area.

What to do if you find a tick on your dog

1.   Ring your vet or an emergency animal hospital first if your dog has any signs at all. Do not spend time on anything else. If your dog seems completely well, ring anyway for advice, because a clinic can tell you what to do next and whether to come in.

2.   Remove the tick as soon as you can, if you are able to do so safely. Use a tick removal tool or fine tipped tweezers, grip the tick right against the skin at the head end, and lift it away without squeezing the body. If you are unsure, your clinic can talk you through it on the phone. Do not apply methylated spirits, petrol, oils or a lit match, and do not try to make the tick release on its own.

3.   Keep searching. Where there is one tick there are often more, and finding one is not the end of the job. Search the whole dog carefully, particularly forward of the front legs.

4.   Keep the tick if you can, sealed in a container, so it can be identified if your dog becomes unwell.

5.   Keep your dog quiet and cool. Excitement, exercise and heat all make tick paralysis worse. Carry a small dog rather than letting it walk to the car.

6.   Do not offer food or water if your dog is showing any signs. A dog with a weakened swallow can inhale food or water, which causes a serious secondary problem on top of the original one.

7.   Go to the vet even if your dog seems fine. Signs can appear after removal, and a clinic will tell you what to watch for and over what period.

What happens at the vet?

Your veterinarian will assess how advanced the paralysis is and discuss treatment on that basis. Treatment commonly involves a tick antiserum that acts against the toxin, along with supportive nursing care while the dog recovers. Dogs are usually hospitalised, because the critical period continues for some time after treatment begins and recovery is not immediate.

Your vet will also search the dog thoroughly and may clip the coat, sometimes quite short, to be certain no tick has been missed. It is worth being prepared for that. A clipped coat grows back, and a missed tick can undo everything else.

Severity varies enormously, and so does what is required. Your veterinarian will explain what your individual dog needs, what the likely course looks like, and what it involves. Some dogs recover uneventfully; others need intensive support. It is a serious condition and honest conversations about it are better than reassuring ones.

Does removing the tick end the risk?

No, and this is the misunderstanding that causes the most harm. Toxin already injected continues to act after the tick has been removed or has dropped off on its own. Signs can appear for the first time, or get worse, in the period after removal.

Treat tick removal as the start of a watching period rather than the end of the incident. Ask your vet how long to watch and what specifically to watch for, and act on the first sign rather than the third.

How to prevent tick paralysis

Prevention has three parts, and the first is the one people skip.

1. Search your dog every day

During tick season, run your fingertips slowly through the coat, applying enough pressure to feel small lumps at skin level. Start at the nose and work backwards. Most ticks are found forward of the front legs, so give the face, lips, ears, under the chin, the neck and the shoulders the most time, then check the armpits, between the toes, the groin, under the tail and the tail itself.

Long coated dogs take longer and need more care. Many owners in high risk areas keep the coat clipped short through the season simply to make searching reliable.

2. Use a tick prevention product

Prevention products reduce risk substantially, and most veterinarians in tick areas regard tick paralysis as largely preventable in dogs when prevention is used properly and consistently. What matters is using the right thing correctly:

•    Check the product is registered for dogs, and for a dog of your dog’s weight and age.

•    Check the approved label for what it claims against paralysis ticks specifically. Not every flea product covers paralysis ticks, and coverage periods differ between products.

•    Follow the label for how often it is applied or given, and diarise the next dose. A lapsed preventative is the most common failure point, not a failure of the product.

•    Consider your dog’s lifestyle when discussing options with your vet. Swimming and frequent bathing matter for some product types.

•    Never use a dog product on a cat.

No product replaces the daily search. Use both.

3. Make the yard less attractive

•    Keep grass mown and shrubs trimmed back, particularly along fence lines and around the areas your dog rests.

•    Clear leaf litter, compost piles and rubbish that hold humidity.

•    Cut back overhanging branches that let possums cross into the yard.

•    Keep dogs on lead and out of dense vegetation on walks during the season.

Four things people get wrong about paralysis ticks

•    "My dog is only in the backyard." Possums and bandicoots bring ticks into suburban yards. Yard only dogs get tick paralysis.

•    "I found the tick, so we are fine." Signs can appear after removal, and there is frequently more than one tick.

•    "It happened before and my dog recovered, so there is some immunity." Recovering from tick paralysis does not protect a dog from getting it again.

•    "It is winter, so there are no ticks." Risk falls in winter but does not disappear, and in the northern part of the range ticks are present year round.

Frequently asked questions

What are the first signs of tick paralysis in a dog?

Usually a change in the bark and weakness or wobbliness in the back legs, often with vomiting or retching. These progress to difficulty standing and then to laboured breathing. Any of them warrants an immediate call to a vet.

How long does it take for a paralysis tick to affect a dog?

The adult female does not usually inject detectable amounts of toxin until around the third day of attachment, with the largest amounts around days five and six. This is why daily searching works, and why signs can appear days after the walk that caused it.

Can a dog still get sick after the tick is removed?

Yes. Toxin already injected continues to act, so signs can appear or worsen after removal. Removal starts a watching period rather than ending the incident.

Do cats get tick paralysis?

Yes, and they can become critically ill. Cats are also at risk from permethrin containing dog tick products, which must never be used on them.

Can tick paralysis be prevented?

Risk can be reduced substantially by combining a suitable prevention product used according to its approved label with a thorough daily search during the season, plus sensible yard management. No single measure is sufficient on its own.

Before tick season builds

Spring and early summer are the busiest period for paralysis ticks along the east coast. The dogs that come through the season without an incident are usually the ones whose owners searched daily and kept prevention current, not the ones who were lucky.

Scriptly stocks APVMA approved flea and tick prevention for dogs, delivered to your door. Check what your current product covers and when the next dose is due, and speak to your vet if you are unsure whether it is right for a paralysis tick area.

This article is general information for Australian pet owners. It is not veterinary advice and it does not replace an examination. If you suspect tick paralysis, contact a veterinarian immediately. Always follow the approved label directions for any product you use.

Sources

Australian Museum, Australian Paralysis Tick (Ixodes holocyclus) species profile. Australian Centre for Disease Control, Paralysis from tick bites factsheet. Australian Pesticides and Veterinary Medicines Authority, Veterinary Labelling Code, specific labelling requirements for ectoparasiticides for dogs and cats.