Thor­oughly ticked off

Eye­less, minis­cule, un­able to fly or jump and a car­rier of the grim Lyme dis­ease, the com­mon sheep tick is a most unattrac­tive and ob­jec­tion­able crea­ture, con­cludes David Pro­fumo

Country Life Every Week - - Contents -

David Pro­fumo finds the tick to be unattrac­tive and ob­jec­tion­able

Wide­spread in high sum­mer, and a vec­tor of sev­eral se­ri­ous dis­eases, the com­mon sheep tick is an ec­topar­a­sitic blood-suck­ing mite that must qual­ify as one of the almighty’s more re­bar­ba­tive cre­ations. an arthro­pod be­long­ing to a het­ero­ge­neous or­der of spi­der-like an­i­mals (Aca­rina), there are more than 20 species of tick in Bri­tain, in­clud­ing one con­fined to tor­toises. sev­eral bite hu­mans—although they are said to shun red­heads—and the chief cul­prit is

Ix­odes rici­nus, also known as the cas­tor­bean tick.

eye­less, minis­cule, un­able to fly or jump, the ma­ture adults have four pairs of legs (they’re not in­sects), a hard ex­oskele­ton pro­tected by a scale-like shield and a red­dish ab­domen that swells up and turns grey­ish when en­gorged af­ter a blood meal—thus the ex­pres­sion ‘as tight as a tick’. The larger fe­male can then mea­sure more than half an inch long and re­sem­bles a re­pul­sive minia­ture hag­gis.

Tykes, keds and taids have long been known as live­stock pests—pliny called them ‘the foulest and nas­ti­est of crea­tures’. They cause an­i­mal dis­eases such as sheep-trem­bling ill, red­wa­ter fever in cat­tle and loup­ing ill that’s fa­tal to red-grouse chicks. From Tu­dor times, the word—like ‘louse’—has been a term of ver­minous be­lit­tle­ment (one of eve­lyn Waugh’s de­trac­tors liked to re­fer to him as ‘that aw­ful lit­tle tick’), but there have been few ver­nac­u­lar so­bri­quets for it. How about Beelze­bub’s beauty spot?

With a par­tic­u­lar lik­ing for bracken, moor­land and bil­berry, rici­nus in­fests wood­land and moors from the New For­est to ur­ban parks, wher­ever it’s damp and hu­mid. The im­ma­ture tick lurks on veg­e­ta­tion await­ing the prox­im­ity of a po­ten­tial host, sen­so­rily de­tected by its Haller’s or­gan, which re­sponds to changes in car­bon diox­ide. it then latches hooked limbs onto a con­ve­nient feather or hair. The very thought of them, blind and quest­ing in the un­der­growth, gives me a psy­chogenic itch.

Their three-host life­cy­cle lasts sev­eral years and be­gins when the lar­vae hatch and search for small mam­mals, bats or birds. These ‘pep­per ticks’ are the size of a Coun­try Life full stop. af­ter a moult, they meta­mor­phose into nymphs of poppy-seed di­men­sions, which are re­spon­si­ble for the ma­jor­ity of hu­man bites. Fi­nally, the adult seeks out a large her­bi­vore—deer, sheep, boar—mates for a week in its fur, then drops to the ground where eggs are laid. Our overly large pop­u­la­tion of var­i­ous deer species seems to cor­re­late with the mod­ern abun­dance of ticks in Bri­tain.

Not all ticks are in­fected, but many pass on var­i­ous zoonitic dis­eases to hu­mans, in­clud­ing the en­cephali­tis virus. Most no­table is the spiro­chetal bac­terium Bor­re­lia burg

dor­feri, which is car­ried in its sali­vary glands and causes Lyme dis­ease. Usu­ally bit­ing soft, damp ar­eas of the body by night, the par­a­site bur­rows its soft ros­trum into your flesh and in­jects an an­ti­co­ag­u­lant saliva along with his­tamine binders (most vic­tims don’t even re­alise they’ve been bit­ten).

The longer a tick is in place, the higher the chances of in­fec­tion. re­move it by grasp­ing with pointed tweez­ers as close as fea­si­ble to the skin or use a wire loop; never twist or squeeze, as this may prompt the tick to re­lease bod­ily flu­ids, as can the folk reme­dies of burn­ing or ap­ply­ing petroleum jelly. if you break off the mouth parts or spurs, they may cause fur­ther ir­ri­ta­tion. One of the more del­i­cate ma­noeu­vres of my life was re­mov­ing a tick em­bed­ded in the an­ti­he­lix of my baby grand­son’s pale outer ear.

Tick fever has fea­tured in med­i­cal writ­ings for cen­turies, but Lyme dis­ease was only named in 1975, fol­low­ing di­ag­no­sis in the Con­necti­cut town­ship of Old Lyme. The first recorded case in Bri­tain was in 1977, although analysis of tick spec­i­mens in the Nat­u­ral His­tory Mu­seum in­di­cates the bac­terium was present in Vic­to­rian times.

in many (but not all) cases, the ini­tial tell­tale symp­tom is Ery­thema mi­grans—a red, bull’s-eye rash fol­lowed by fa­tigue, joint pain, nau­sea or other flu-like symp­toms. Un­di­ag­nosed, it can at­tack the ner­vous sys­tem and prove fa­tal, although prompt treat­ment with an­tibi­otics is usu­ally suc­cess­ful. it’s of­fi­cially es­ti­mated that 2,000 to 3,000 new cases may oc­cur here an­nu­ally. There is cur­rently no vac­cine for Lyme dis­ease.

in the 1990s, an an­i­mated american car­toon se­ries called The Tick lam­pooned su­per­heroes such as spi­der-man and there will be a live-ac­tion TV se­ries this sum­mer. in 1993, a grotesque tick-flick—var­i­ously en­ti­tled Ticks or In­fested—in­volved a group of Cal­i­for­nian mis­fits con­fronting mu­tant bugs (the re­sult of steroids from a lo­cal mar­i­juana farm) and, although some of the spe­cial ef­fects were rudi­men­tary (model arthro­pods be­ing pulled along on fish­ing ny­lon), it was a spec­tac­u­lar gorefest that some en­ter­pris­ing dis­trib­u­tor ought to reis­sue on dvd. ‘it’s not nice to mess with Mother Na­ture,’ con­cluded the trailer. No doubt pliny would have agreed.

‘One of Eve­lyn Waugh’s de­trac­tors re­ferred to him as ‘that aw­ful lit­tle tick’

Not very ro­man­tic: in the UK, the sheep tick (Ix­odes rici­nus) is the prin­ci­pal agent in the spread of Lyme dis­ease, which can cause skin le­sions, car­diac ab­nor­mal­i­ties and arthri­tis

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