Paralysis ticks strike fear into the hearts of any pet owner. We discuss what to do to reduce the risks of tick paralysis and what signs to look for in your pet.
Unfortunately avoidance of paralysis ticks is not always possible. No tick preventative is 100% effective and it only takes one tiny tick to cause a big problem. The paralysis tick of Australia, Ixodes holocyclus tends to occur in a 20km wide band along the east coast of Australian in Spring to Autumn particularly when rain follows a period of warm weather. Ticks are heading further south due to warmer weather conditions and are now found as far south as Lakes Entrance in Victoria.
Why should I worry about ticks?
Not all ticks cause a problem, there are 75 different species of ticks in Australia, but only this one species Ixodes holocyclus causes paralysis (other ticks can spread disease and cause anaemia). Dogs are particularly sensitive to the toxins the female paralysis tick excretes while feeding on blood.
Just one tick can kill a dog within a week, even a large, robust dog. The toxins the tick excretes bind to the neuromuscular junction, causing paralysis, usually of the back legs first, but progressing to all the muscles in the body and most critically, those that help your pet breathe and swallow.
The lifecycle of a tick
Female ticks can lay up to 3000 ticks after a blood meal. Only a small fraction of the eggs survive (ideally they love moist leaf litter) and once they hatch the larval tick must get a blood meal to survive. It does this by climbing up grasses and vegetation and waving its arms around in search of a passing host.
Usually this would be some form of native wildlife like kangaroos and bandicoots, but can include pets and humans. These nymphs then moult to form the adult tick. Only the adult female tick causes tick paralysis and it will need to be attached for 2-7 days before the toxin from the salivary glands starts to affect your your pet. This is where daily tick searching can help detect ticks before they start causing a problem.
Is it just dogs that get tick paralysis?
Dogs are particularly susceptible to tick paralysis, but ticks can also effect human children, horses and cats. Wildlife usually are immune to the effects of the tick toxin and in particular bandicoots will carry large numbers of ticks. Cats are usually fairly good at grooming out their ticks, but should be tick searched around the face and neck where it is harder for them to reach attached ticks.
What happens when the tick attaches?
The toxin from the tick saliva is absorbed as the female tick feeds. Ticks start out only a couple of millimeters in diameter, but slowly get bigger and bigger as they feed. A female tick will stay attached for up to 10 days and just before the tick has finished feeding there is a rapid phase of engorgement when a large amount of toxin is injected.
This stage at around the 5-7 day mark is when the signs of tick paralysis often get particularly severe. A tiny tick that has only just recently attached may cause mild paralysis, while one that is 0.5-1cm in diameter and has been attached for a while is more likely to be fatal.
What does the paralysis tick look like?
It is not always easy to identify a tick. The body colour can vary depending on the age of the tick and the ‘bad’ ticks look very similar to the ‘good’ ones (the other 74 species of ticks that occur in Australia). The only conclusive way to identify a paralysis tick is by the colour of the legs. Mature Ixodes holocyclus has 8 legs, on each side there is one brown leg at the front and back, but the middle two legs are white.
Paralysis ticks start around 1mm in size (the nymphs are also very small), but can reach 1cm in size when fully engorged. The body colour of a tick will vary depending on the age of the tick and is not a reliable way to identify it.
How to remove a tick
Ticks are designed to stay in the skin, with backward-facing barbs on the feeding parts that hold them in place while your pet is moving around. Try to remove a tick by grabbing just where the tick’s feeding parts enter the skin, rather than squeezing the body of the tick. You can get specific tick pullers to do the job or just use tweezers.
Ideally you want to twist to loosen up those barbs, rather than just pull. Avoid using metho, a lighter or any other dangerous tactic to remove a tick. It is not necessary to kill the tick first (though in people, the advice is somewhat different).
The most important thing is to get the tick off as quickly as possible. As soon as the tick is decapitated, it can’t inject any more toxin, which is the aim of speedy tick removal. Any tick left under the skin will be treated like a splinter and will work itself out.
If your pet is not allowing you to remove the tick (perhaps it might be on the face of an aggressive dog, put some Frontline or pyrethrim on a cotton tip and dab it on the tick).
Once removed, keep the tick (dead or alive) to show your vet, at least then you will know whether to be concerned. Your vet will identify the tick and based on the size and signs your dog is showing
Even when using proper preventatives ticks 1 in 10 ticks can still attach to your pet, so it is still necessary to tick search daily. It is estimated that 80% of ticks are attached on the head and neck, as they will move towards the carbon dioxide being breathed out by your pet. Be systematic and search all over, but pay particular attention to the head and neck and make sure you check inside the mouth and ears. If you live in a tick area and you have a very hairy dog, consider shaving your pet during tick season to make searching easier.
Tick poisoning is not immediate. Signs can take up to 28 days to appear, or may occur within a few days. Activity and high temperatures can hasten and worsen signs so it is important to keep your pet cool (but not cold) and quiet until you get them to the vet. Also avoid giving food and water, as aspiration pneumonia can develop due to swallowing difficulties.
The poisoning causes:
- A change in bark or voice
- Loss of appetite
- Coughing, particularly a soft moist cough
- Vomiting or retching
- Weakness in the back legs
- Partial facial paralysis (particularly if the tick is attached to the head)
- Excessive salivation or difficulty swallowing
- Panting, noisy breathing or difficulty breathing
As tick paralysis progresses, your dog may be unable to stand, will have breathing difficulties and can develop respiratory arrest.
If you notice a tick, take your dog to the vet to get the tick identified and to gain advice on treatment, particularly if the tick is large or has been attached for more than 24 hours. If your dog is showing clinical signs, they can actually worsen even after administration of the anti-toxin.
The anti-toxin takes 6-8 hours to start working and it will take up to 48 hours for the toxin to be removed. Unfortunately the anti-toxin does not remove the toxin that has already bound to your pet’s neuro-receptors, so worsening of signs will occur for around 24 hours before your pet gets better.
This is why the key strategy when treating ticks is early intervention. The ‘wait and see’ approach will often result in your pet ending up needing intensive care and a ventilator to breathe.
- Do not offer food or water-swallowing as ability can be impaired.
- Keep your pet quiet and calm.
- Avoid exercise and heat.
- Get your pet to the vet if you find an engorged tick, or your pet is showing any of the above signs (there may be a tick you can’t find). Early intervention is important!
- If you have the tick, take it with you.
Immunity to ticks
Even though some wildlife can develop tick immunity, dogs rarely do. Immunity would require frequent low level exposure and it would be difficult to do this safely, year-round. Dogs are particularly susceptible to tick paralysis and if they do develop immunity it rarely lasts more than 12 months, so each tick season they need to build up immunity again.
Some dogs never develop any level of immunity and older pets and certain breeds are more prone to the effects of the tick toxin. In general, using a tick preventative and tick searching is the most effective and safe way to protect your pet.
Tick prevention strategies
- Use a fortnightly tick preventative (Frontline or Advantix ) or tick collar (Kiltix).
- Tick search daily.
- Avoid tick shampoos, rinses or powders –they last at best 24 hours.
- Keep lawns short and avoid walking your pet in long grasses.
- Fence off any scrubby or bushy areas in your yard (particularly if you have bandicoots nearby).
- Keep your pet’s coat short to make tick searching easier.
- Walk your dog on a leash so you can keep him on clear grassy areas during tick season.
Common tick myths
Dogs develop immunity to paralysis ticks – unfortunately this is not usually the case. Tick season is not year-round in most areas of Australia. If your dog did manage to develop some level of immunity, this does not appear to carry through to the next year. Relying on natural immunity is a sure way to get your dog killed by one of those puny ticks. Research has shown if natural immunity develops it barely lasts 12 months.
Leaving the head in when removing a tick is bad – not really the case in pets, more the case with humans. If the tick is dead, no more toxin is going into your pet, so it is best to remove the tick rather than worry about killing it first and therefore delaying treatment. You do however want to avoid squeezing the body of the tick while removing it, just use a tick puller or tweezers (or long fingernails) to get in under the body where the mouthparts meet the skin.
Homeopathy works for tick paralysis – one common homeopathic treatment is Ledum every 2 hours for 8 hours. There is no research to show this works and it simply delays treatment, meaning that your pet is more likely to be in end-stage tick paralysis needing intensive treatment by the time you finally get to the vet.
Also avoid using tick shampoos, rinses and ‘natural’ tick remedies. None have been shown to protect your pet. The most natural way to protect your pet is to do a thorough tick search daily during tick season.