Paralysis Tick Ixodes holocyclus.
What are ticks?
Ticks are small arthropod parasites that suck blood from animals. While there are a number different ticks, the main tick that we as veterinarians, and you as pet owners need to worry about is the Paralysis ticks (Ixodes holocyclus) generally called the "dog tick" or "paralysis tick" in N.S.W. and the "scrub tick" in Queensland.
Paralysis ticks are among the most dangerous parasites to affect your pets. Thousands of dogs and cats are paralysed by ticks every year and many die from the toxic effects of tick venom. The paralysis tick is the main tick of concern for pet owners.
Where are paralysis ticks found?
Paralysis ticks occur naturally on the eastern seaboard of Australia from North Queensland to Northern Victoria and even parts of Northern Tasmania. In the northern parts of Australia paralysis ticks may be found all year round while in the southern areas, the season begins in spring and finishes in late autumn. Paralysis ticks are not indigenous to the Goulburn district however we see cases in Goulburn when pets go to the coast for a day trip or a holiday. While visiting a tick region, they pick up a tick, come back to Goulburn and start showing the signs of tick venom toxicity a few days after arriving back in town. On rare occasions during summer, ticks can inadvertently travel back in camping equipment (fomites) and can attach to pets that have never left town. Other fomites (materials that can transmit/carry ticks) out of a tick area and back to a pets home include plants, clothing, and any article to which a tick can cling.
Distribution of Paralysis Ticks in Australia.
The Goulburn region has its own tick which is found on wombats and some of the other local marsupials like possums. Our tick is not a paralysis tick; nevertheless it could have the potential to carry tick born diseases if they ever get into the region. The local tick goes by the name of Aponomma auruginans.
Tick Identification - be alert - know your ticks and know when they are most likely to be active!
What is the life cycle of the paralysis tick?
Ixodes holocyclus commonly uses native animals as hosts, with long-nosed bandicoots (Parameles nauta); the giant brindle bandicoot (Isoodon torosus), possums and echidnas being the most usual but wallabies, kangaroos and koalas are also carriers of paralysis ticks. As the most common host, bandicoots can carry very large numbers of engorging females without any apparent side effects or toxicities.
Paralysis ticks will attack man, domestic dogs and cats, fowls, sheep, calves, goats, foals, pigs, rats, mice, guinea pigs and ferrets. Dogs are the most commonly infected of all domestic pets.
The paralysis tick uses three hosts to complete its life cycle. As an egg it hatches on the ground to become a larva. It then climbs onto nearby vegetation and waits to attach to its first host.
After gorging on blood, it drops off to the ground, moults and becomes a nymph and attaches to its second host.
Again it engorges, drops to the ground, moults and attaches to its third and final host. Here it engorges once again and when replete drops off to lay as many as 3,000 eggs in two weeks - before it dies.
Ticks do not always attach themselves as soon as they reach a suitable host. They may meander about the skin for a day or so, males looking for an unfertilized female, and females for a place to attach and gorge themselves for as long as three weeks.
What are the signs of paralysis tick infestation and symptoms of tick paralysis?
An infested animal may scratch, lick or bite itself in an effort to remove ticks. If there are ticks on the ears an animal may shake its head repeatedly. As the ticks engorge and the host (your pet) takes on board more venom the symptoms of paralysis begin to occur.
The earliest signs of tick paralysis often suggest that your pet has something caught in its throat or the back legs are not working properly. Other symptoms include:
vomiting, retching and coughing
heavy, laboured, rapid breathing, often with a grunt
alteration of your pet's vocal sounds
loss of coordination in the hind legs
loss of appetite
progressive paralysis to include the forelegs
While signs vary from patient to patient and not all cases follow this simple progression of symptoms, the usual course is a progressive paralysis with subsequent loss of use of all four limbs starting with the back legs. Some animals, especially cats, may become distressed, anxious and confused. Eventually there is an inability to breathe in enough oxygen as the lungs develop congestion and the chest muscles become paralysed.
The time taken from the onset of symptoms to death from paralysis can be as little as 2-4 days after attachment. Not just the adults, but larvae and nymphs can produce toxic reactions in the host.
What to do if you find a tick on your pet.
If you notice a tick on a pet that is not displaying signs of tick paralysis, remove the tick straight away. To do this, grasp the tick firmly where it attaches to your pet’s skin and give a quick sideways pull. It is better not to try and kill the tick first as the dying tick may inject more of its potent toxin into your pet. Do not panic if you pull the tick out and leave the head still attacked to the skin - the head that is left behind at worst will cause a splinter or foreign body-like reaction but otherwise will do no harm. If you are not confident removing the tick please call us immediately to make an appointment to have it removed.
It's always a good idea to thoroughly examine your pet once a day when visiting tick country. Start at the head and gently but firmly palpate the entire body checking inside the ears, around the corners of the mouth, under the arms and in the groin and around the anus, vulva in females and prepuce in males. Check the webbing between toes. It doesn't take long to carry out a thorough inspection of your pet and this should be done even if you are using some sort of tick preventative. Remember - there will often be more than one tick attached to a pet so don't just stop searching once you've found and removed one.
If you visit the coast frequently it is always a good idea to keep a tick remover handy - there are many types available from pet shops and veterinary clinics. The one we favour is the Awnbeck Tick Remover which can be sterilized, is durable, and made of metal, quite strong and easy to use on all manner of animals
How does the tick cause paralysis?
The tick sucks blood from the host and secretes saliva that contains toxins which are absorbed and cause signs of paralysis and poisoning.
What to do if your pet shows signs of tick paralysis.
Keep your pet calm and in a cool, dark place until you can get your pet to our clinic.
Do not offer food or water as this may lead to pneumonia and breathing difficulties if your pet cannot swallow properly.
Seek veterinary attention as soon as possible.
What is the treatment for tick paralysis?
Tick paralysis is an emergency.
Treatment of tick paralysis includes searching for and removing all ticks. This may include clipping the animal completely and/or the use of medication to kill remaining ticks. Tick antiserum is administered to counteract the toxin and supportive care is provided during recovery. This can be costly in comparison to what it would cost to use tick prevention initially.
Other specialized procedures such as sedation and treatment for respiratory complications may be vital to your pet's recovery and some pets may require hospitalization for several days. Antibiotic cover is often indicated to prevent secondary infections, particularly of the lung.
Some animals will survive without treatment but the majority will either die or suffer terribly while they try to recover, or suffer on-going complications unless given the appropriate treatment. The chances of success with treatment decrease the longer treatment is delayed and the further the symptoms progress however there is no real way to tell which pets will survive so the only way to ensure the maximum chance of success is to get your pet to the clinic for treatment as soon as possible.
Prevention of tick paralysis.
There are some very good tick control products available, call the clinic for advice or ask at your next consultation which products will suit you and your pet's needs. We recommend that any tick prevention programme begins at least a week before going into tick country and continues for several weeks after returning home.
However, no tick prevention is 100% effective and should always be used in combination with daily searches of your pet. Searching your pet shouldn’t cease once you return from tick-affected regions but should continue for at least 7 days after returning home. Use your fingers to feel over the entire body, especially under the collar, on the face and around the front of your pet. Don’t forget to check carefully between the toes, under the lips and in the ears.
We are more than happy to show you how to do a thorough tick search, please call us to discuss.