ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

The Australian Scrub Tick

Updated on March 9, 2012

The Australian scrub tick, also known as the paralysis tick or dog tick, is a minute parasite that delivers a paralyzing toxin and if not removed can eventually cause death, even in human hosts.

Ticks are notorious for the many serious diseases and ailments they can transmit or cause, but of the 59 species occurring in Australia, the scrub tick, Ixodes holocyclus, is one of the worst offenders. These tiny parasites are not insects but arachnids, members of the spider group.

They are found in eastern Australia between the mountains and the coast from lower Cape York Peninsula down into far eastern Victoria. They are most prevalent within 16 kilometers of the coast but they have been found further inland and are particularly abundant in rainforests.

Birds carrying nymphs of this species have even been recorded in the Canberra area, but whether the tick has become established there has not yet been determined.

Source

No Preferred Victim

Unlike many other ticks which feed only on the blood of certain animals, the scrub tick is not particular and any warmblooded animal will do.

The most common host is the bandicoot but most small and large marsupials, including kangaroos carry scrub ticks, as do spiny anteaters. Many birds are affected, including chickens, ducks, parrots, crows, magpies, curlews and butcherbirds; pets, especially dogs; stock such as horses, cattle, sheep, goats and pigs; mice and rats. There have even been reports of zoo animals, particularly monkeys, carrying scrub ticks. Humans who visit tick-infested areas or come into contact with infested animals are also liable to be chosen as hosts.

Ticks may be found anywhere on a host's body, but tend to prefer softer skin in areas such as the groin and external genitals, the corners of the mouth and eyes, the ears and the head generally. On humans they tend to hide in folds of the skin or above the hairline and have been known to attach themselves to the eardrum. On birds they keep mainly to the head and to bare or sparsely-feathered areas.

Wrong Diagnosis Results in Death

Scrub tick paralysis is caused by a poison in the saliva which causes a progressive muscular paralysis in the host that may eventually affect respiration and heart function, resulting in death. Actually, once a tick is removed the host begins to recover and in severe cases an antitoxin is available.

However, in certain cases where the doctor has not known that the patient was in tick country the symptoms of approaching tick paralysis have been confused with some other disease such as infantile paralysis. There have even been cases reported in which a bandage has been left covering the unrecognized tick until the victim died.

Ticks should never be squeezed as more poison may be thus injected into the host's body. They should be carefully plucked out using either tweezers or the 'v' of slightly open scissors.

Two related species Ixodes cornuatus and Ixodes hirsti are associated with similar paralysis, but further study is required before their significance can be assessed.

Responsible For Many Ailments

Scrub ticks are associated with various other ailments and diseases. Allergic reactions such as itching, rashes, swelling of lymph nodes and respiratory distress have been noted and are in some cases severe.

This species is one of several responsible for the transmission of Q fever, a disease exhibiting pneumonia-like symptoms and caused by the microoganism Coxiella burneti which the ticks can carry. Most noted in humans, natural occurrences of Q fever have been detected in dogs, cattle, sheep, kangaroos and bandicoots.

Although the disease is usually transmitted by a tick's bite, infections in humans are thought to occur mainly through contact with the excretions and secretions of infected animals.

Scrub ticks are also thought to be associated with the spread of Queensland 'tick typhus', a human disease occurring in coastal Queensland.

Complex Life Cycle

Ticks have a complex life cycle consisting of three parasitic stages. Immature forms are no larger than the head of a pin and are oval in shape.

Thousands of these tiny creatures climb grass blades to await a passing host.

As soon as a tick touches the skin of a host, its sharp mouthparts pierce the skin and the tick begins to rapidly engorge itself with blood, becoming partially buried in the skin. In only four days a female tick can expand to as much as 400 times her original size, looking something like a blood blister, her shape now only slightly oval. Size increases in males are not nearly so dramatic.

The tick then drops off to digest its meal, moults and repeats the process. The female feeds during all three stages -larva, nymph, adult - the male feeds from a host only during the first two stages. Females always feed until fully engorged and paralysis is usually associated with the adult female during her final meal. While she consumes her last draught, a male aboard the same host finds her and mates with her. The male has even been observed to refresh itself with a drink from the female body during mating, by piercing her body with its mouthparts.

Fully engorged and fertilized, the adult female drops from the host, lays thousands of eggs in a single batch, then dies. On hatching some seven to nine weeks later, the tiny larvae seek hosts and renew the cycle.

Comments

    0 of 8192 characters used
    Post Comment

    No comments yet.

    working

    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, hubpages.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://hubpages.com/privacy-policy#gdpr

    Show Details
    Necessary
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
    Features
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Marketing
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Statistics
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)