There are many types of ticks. Not all cause paralysis. The brown dog tick ( Rhipicephalus) is not the same as the paralysis tick ( Ixodes holocylus). Don’t get caught out by supermarket products that say they protect against the brown dog tick – this is not something you want and will not protect against the paralysis tick. Brown dog tick and bush ticks are not life threatening to dogs and cats but are irritating and can cause anaemia.
The paralysis tick is light grey in colour. The 8 legs all come from the front part of the body near the head. On the underside there is often a dent or line. The tick may be any size from a pinhead to a thumbnail ( when fully engorged with blood). When the paralysis tick attaches to your pet it produces a toxin which it injects into your pet while it feeds (sucks blood)
There is no relation between the size of the tick and the severity of clinical signs. It depends on the tick’s DNA, how toxic it is. Ticks do get larger as they feed and do inject more neurotoxin the longer they are on your pet. Ticks may kill very quickly, within 12 hours (although this is rare). In some areas the ticks only cause weakness of muscles and have no effect on heart and breathing – so dogs can survive well.
In most paralysis ticks the DNA produces a neurotoxin that causes problems in neuromuscular junctions causing :
- Laryngeal dysfunction ( swallowing difficulties and changes in voice)
- Megaoesophagus (swallowing difficulties)
- Cardiac dysfunction ( heart problems)
- Pulmonary oedema ( lung congestion)
- Muscle weakness progressing to paralysis
- Inability to regulate body temperature
Sometimes ticks will cause only a local reaction. Often a tick on the face or around the ear will cause facial paralysis (drooping) on that side, the third eyelid may come across, eyelid opening narrow and change in pupil size (may look like squinting)
Any paralysis tick can kill. Never underestimate a tick. Remove all ticks as soon as possible.
Prevention of Tick Paralysis caused by the Paralysis Tick (Ixodes holocyclus)
- Recognise the signs of tick paralysis and seek early treatment. Treatment is much less expensive and more successful if given early. Often the first sign is a change in the voice and a glazed look in the eyes.
There are three main signs to look for:
- Weakness of legs – a slowness in walking, a wobbly gait, or a tendency to lose balance or fall over.
- Vomiting or dry retching. Sometimes drooling (salivation)
- Difficulty in breathing, or a change in the breathing pattern. Sometimes gagging or coughing.
(Important – sometimes only ONE of the three signs is present, sometimes two, sometimes all three.)
If you see one or more of these signs, SEARCH your animal’s body for a tick. Search the whole body, but especially the head and neck areas, including around the ears. If you find a tick then your pet almost certainly has tick paralysis. You may find a little hole in the skin, like a crater or a small scab. This could be the place where a tick has been, in which case the problem is still likely to be tick paralysis. Or you may not find anything. However, if it is the right time of year for ticks, and you are in a tick area, then it still could quite easily be tick paralysis. Ticks can be very difficult to find on an animal. If in doubt contact your veterinarian.
- 2. Keep your dog’s coat short if possible.
(Not all breeds are suitable for clipping. If in doubt ask for advice.) Long-haired dogs (eg Maltese, Silky terriers) are very susceptible to tick paralysis as it is hard to find a tick on them, especially if the coat is knotty and matted. Unless the dog is indoors at all times, try to keep the coat clipped to about 2-3 cm long – or brush daily and cut out any knots or matts.
- 3. Avoid high risk areas.
If you allow your dog or cat to wander or run through the scrub or bush during the tick season he is more likely to pick up a tick. Keep grass in yard short.
- SEARCH DAILY for ticks
or at least every second day. Go over or through the coat carefully, especially the head and neck areas. Remove any ticks you find. If you find a Paralysis Tick observe the pet carefully for 24 hours, and if any signs of paralysis develop, contact your veterinarian. (Paralysis can still develop even if the tick has been removed.)
- 5. ACARICIDAL CHEMICALS
No chemical should be relied on to be 100% effective in preventing tick paralysis. Some insecticides/acaricides are dangerous especially to cats, puppies. or to any animal which is old or unwell.
In our practice we have found the following products useful as part of a tick control strategy:
(Note that in all cases the manufacturer’s recommendations for use of the product should be read and followed.
Frontline Spray – Merial – spray every 3 weeks
Advantix – Bayer – apply to back of neck every 2 weeks
Preventic Collar – Virbac – replace every 2 months (8 weeks)
Frontline TopSpot – Merial – apply to back of neck every 2 weeks
Proban (Cythioate) tablets or liquid, given orally every second day – Boehringer Ingelheim
Kiltix Collar – Bayer – replace every 6 weeks. These collars can cause agitation and muscle tremors.
Permoxin rinse or spray – Dermcare Vet – spray daily or rinse twice a week
Some organo-phosphate rinses (Nucidol, Asuntol). – rinse twice a week
What do I need to do after my pet has been treated for tick paralysis?
PREVENT RE-INFESTATION WITH TICKS
Following treatment for Tick poisoning, you might expect your pet to develop an immunity, but the passive shorterm immunity (a few days) conferred by the serum prevents the development of any long term effective immunity. During the two-month recovery period, the pet is actually more susceptible to another bout of Tick Poisoning if an adult female Paralysis tick attaches and injects her poison. Therefore it is important to keep ticks off your pet especially during this period.
Paralysis ticks can kill. At the time of going home, your pet may be walking and breathing normally and appear outwardly normal, or alternatively may still be showing some of the signs of tick paralysis. It will take at least three weeks for your pet to be 100%, and sometimes 6 weeks.
- FOOD & WATER.
Tick poisoning prevents the dog from swallowing properly. (They get megaoesophagus from effect of tick toxin on neuromuscular junctions and laryngeal problems) Food or water given too early may cause choking, coughing, or inhalation pneumonia which can be fatal. Unless the dog has already been eating or drinking in Hospital, we recommend the following:
(a) The first 24 hours offer water only, in small amounts frequently. If vomiting or coughing occurs, stop offering water.
(b) The second day you can offer soft easy to swallow foods in small amounts. a little often is better than one big meal. If coughing or vomiting occurs, stop. In any case the pet’s total food intake should not exceed half of its normal daily food intake, at this stage.
(c) The third day, if there have been no problems, return to normal daily feeding and make water freely available.
- PROGRESSION OF SIGNS.
When a dog is first treated with Tick Hyperimmune Serum, there is a time lag before it becomes effective, so that the pet’s condition may still deteriorate for a day or more following initial treatment. After this it will normally stabilise or start to recover. Following a stay in hospital of 24 hrs or more, when a pet is sent home it should not get any worse than it is at the time of discharge from hospital.
If it does get any worse, for example if it has greater difficulty walking, or starts coughing or vomiting, you should contact your veterinarian as soon as possible.
- SEARCH FOR MORE TICKS.
Although veterinary and nursing staff search every pet thoroughly for ticks while it is in Hospital, it is impossible to guarantee that one may not be missed. It is also possible for a dog to pick up more ticks as soon as it goes home. You should search the coat thoroughly for ticks every day and remove any you find. If you find any large ones (over 2 mm long), call your vet.
- AVOID STRENUOUS EXERCISE OR UNNECESSARY EXCITEMENT
For up to 2 months after suffering from Tick paralysis, your pets body will be slowly recovering from the effects of the poison, even though outwardly it may seem to have made a quick recovery. Its heart, lungs, muscles, and nerves will not be as strong as they were before the disease. Recovery is gradual, and given time, should be complete without any permanent after-effects.
However it is important to avoid strenuous exercise or excitement, especially in the first few days. Taking a dog for a long run, for example, could cause a heart attack. We suggest confinement and rest for the first few days, and avoidance of serious exercise (as with working dogs) for four to six weeks.
Even after effective tick treatment your pet will take 6 weeks for the electrical activity of the heart ( as shown on ECG) to return to normal. Megaoesophagus – swallowing difficulties – also takes many weeks to return to normal (even though they will eat and drink).