Ixodes holocyclus Click to enlarge image
Paralysis Tick, filled with blood Image: Stephen L. Doggett
© Stephen L. Doggett

Fast Facts

  • IUCN Conservation Status
  • Classification

The Australian Paralysis Tick, Ixodes holocyclus, is found in Eastern Australia and is a parasite to native mammals, livestock, pets and even people.


Flattened from top to bottom, overall oval, seed-shaped body. Larvae have 6 legs while nymphs and adults have 8 like the rest of their arachnid relatives.


They are found in a variety of habitats across the humid coastal regions of eastern Australia, particularly wet sclerophyll forests and temperate rainforest areas.


May be found all year round.

Feeding and diet

Mammals are common hosts as are many birds and sometimes reptiles. Domestic animals such as farm animals and pets like dogs are frequently infested.

To find hosts required for their growth and development, ticks wait on vegetation with their legs outstretched and waving slowly until they can make contact.

Life cycle

Larvae or "seed/grass" ticks are tiny (0.5mm) and found mostly in autumn and winter. After 3 different host feedings they then moult to the nymph stage which are about 1mm. Adults are most common from spring to midsummer. Usually only females bite people and other mammals. The bite is usually not notable but may rarely lead to paralysis, allergic reactions and tick typhus.

Danger to humans

They penetrate and suck!

Paralysis Tick bites initially cause local itchiness and a hard lump at the site of the bite with other more serious symptoms presenting themselves over number of days whilst the tick engorges itself. These include flu like symptoms, rashes, an unsteady gait, weak limbs and partial face paralysis.

Other problems associated with Paralysis Tick bites are allergic reactions ranging from mild itching and swelling to potentially life threatening anaphylactic shock.

Children are the most susceptible to problems caused by ticks as they may not be able to communicate they have been bitten and so ticks can be feeding on them for a number of days by which time their symptoms are quite advanced.

If visiting a potential tick infested area it is advised that you wear light coloured clothing (so ticks are more visible), long sleeved tops and pants and ensure that you tuck trouser legs into socks. A repellent can be applied.

If a tick bite is detected it should not be disturbed until the tick has been killed. Reactions to tick bites occur most commonly when a tick is disturbed, not necessarily when it is attached and feeding. If the person bitten has a history of anaphylaxis, they should immediately seek medical assistance to get it removed.

For larval or nymph ticks (they can hardly be seen and look like a tiny speck) the area can be liberally dabbed with insect creams containing permethrin, which should kill the tick. The cream should be applied at least twice with a one-minute interval in between, to make sure it has been killed. The tick can then be left for 24 hours to drop off on its own, or be scraped off with a sharp-edged scraper 60-90 minutes after it has been killed.

If the tick is an adult, take extra care not to disturb it. It should not be touched at all, instead it should be frozen by spraying it liberally with ether-containing sprays, then left alone to drop off by itself. If the tick does not drop off after 24-hours, seek medical assistance to remove it. Do not try to remove it with your fingernails or tweezers as it makes it much more likely for the tick to inject its saliva into the person bitten, and can leave the mouthparts in the skin.

For more information about treating tick bites, please see health department advice here: https://www.health.gov.au/our-work/dscatt/tick-bite-associated-illnesses-resources-for-the-general-public.