Paralysis Tick & Tick Paralysis

Also called: Ixodes holocyclus, paralysis tick, tick paralysis, tick envenomation

• Dogs
• Skin & parasites
• Any — eastern Australia

The female Australian paralysis tick (Ixodes holocyclus) secretes a potent neurotoxin in its saliva that causes a rapidly ascending paralysis and can be fatal. It occurs along the east coast of Australia — from north Queensland through coastal NSW to eastern Victoria — in bushland and humid coastal areas. It is one of the most common preventable causes of death in dogs and cats in these regions.

Signs to look for

• A change or loss of bark/voice
• Wobbliness or weakness in the hind legs, progressing to inability to stand
• Changed breathing — faster, laboured, or grunting
• Vomiting, regurgitation, gagging, retching, or drooling
• Dilated pupils, then collapse

How a vet diagnoses it

Clinical signs together with finding a tick or a tick 'crater'. Ticks can be very hard to find, so recent exposure and signs guide care even when no tick is found.

Treatment

Emergency treatment: tick antiserum (anti-toxin) as soon as possible, removal of all ticks, sedation to reduce stress, and supportive care including oxygen, IV fluids, and sometimes a ventilator. Signs can worsen for 24–48 hours even after the tick is removed.

Monitoring at home

Usually favourable if caught early, guarded once advanced. Recovery and monitoring take days. Prevention is key — daily tick searches (especially the head, neck, and front of the body), year-round preventive products, and avoiding tick habitat.

Who tends to get it

Dogs (and cats) on the Australian east coast, especially in warmer, wetter months, though ticks occur year-round in the north. Native animals are largely immune. Historically estimated to cause paralysis in around 10,000 domestic pets a year in Australia (an older estimate).

Sources

• RSPCA Knowledgebase — Protecting your pet from tick paralysis
• MSD Veterinary Manual — Tick Paralysis in Dogs