Cause

Tick poisoning is caused by the adult stage of the paralysis tick (Ixodes holocyclus). The natural hosts for this tick are our native fauna, especially possums and bandicoots. When a paralysis tick attaches to a dog or cat it ingests blood and also secretes a toxin into the animal, which causes tick poisoning. Paralysis ticks are more commonly found in the warmer months (spring and summer).


Signs of tick poisoning

The clinical signs of tick poisoning usually occur within 3-4 days of the tick attaching.

The signs can be variable but the most common changes include:

*A change in voice (bark/meow sounds different);
*Vomiting/regurgitating or refusing food;
*Weakness in the back legs which may progress to collapse;
*Breathing problems eg they may have a loud pant or slow laboured breathing.
These signs are caused by the tick toxin attaching to the nerve endings (neuromuscular junctions) leading to progressive weakness and paralysis. For up to 36 hours after a tick has been removed from your pet, the toxin remains in the blood stream and will continue to attach to the nerve endings and cause paralysis. For this reason, tick anti-toxin needs to be administered as soon as possible.


Treatment of tick poisoning

If your pet is showing any of the above signs then they require treatment.

Treatment of animals with tick poisoning includes:

*Removal of ticks and repeated searches for other ticks (long-haired or thick-coated animals may required full body clipping;
*Administration of anti-toxin;
*Cage rest and close monitoring especially of respiration (breathing), mobility, bladder function and the swallowing reflex;
*Food and water is removed for a minimum of 24 hours (in some cases, pets may require intravenous fluid therapy to maintain hydration;
*Frontline spray application or tick adulticide rinse, if still swallowing normally oral NexGard administration;
*Administration of a sedative is also often necessary to reduce anxiety and to help with ease of breathing.
Tick anti-toxin is given to prevent further attachment of tick toxin to the nerve endings. It is NOT an antidote so an immediate reversal of clinical signs does not occur. Some animals with tick poisoning will worsen before they improve, however the overall survival rate for animals with tick poisoning is about 95%

Severely affected animals will require additional intensive supportive treatment and care eg oxygen therapy (some may even need to go onto a ventilator), suctioning of oesophageal fluid, chest x-rays, antibiotics etc. Sometimes affected pets need to be transferred to an emergency facility for monitoring whilst on oxygen therapy.


Hospital stay and costs

In most cases your pet will be hospitalised for 2-3 days. Severely affected animals will require longer periods in hospital as recovery is prolonged and they are more likely to suffer complications eg aspiration pneumonia (where vomit or food has been inhaled into the lungs causing infection) or megaoesophagus (dilation of the oesophagus causing regurgitation).

The costs involved with treating pets with tick poisoning vary according to the level of toxicity which determines the level of hospital care and supportive treatment required. This can be difficult to estimate as some cases will deteriorate even with appropriate intervention. The size of the pet also affects costs as tick anti-toxin is expensive and is administered according to body weight.

Mildly affected tick poisoning cases (minimum costs):

*Cats and small dogs <15kg approx $400-600
*Larger dogs >15kg approx $500-800

More severely affected tick poisoning cases (minimum costs):

*Cats and small dogs <15kg $600+
*Larger dogs >15kg $800+

Ongoing intensive supportive treatment (eg if artificial ventilation is required) at referral hospitals for severely affected cases maybe$1000-2000 or more per day.