2013年9月16日星期一

Ordnance Survey Blog » The truth about ticks


By , 27, June, 2011 8:00 am






Today

Today’s blog post comes from Wendy Fox, Director & Chairperson of BADA-UK



Today on the Ordnance Survey blog we have a guest post from Wendy Fox from BADA-UK.



As summer (such as it is) progresses, many of us are getting out and about to enjoy the great outdoors. Of course, there are many health and safety aspects that we should be aware of (such as preparing for adverse weather and preventing walking/running injuries etc.) but how many people think about ticks when it comes to getting out and about?


Vampire ticks: The scourge of the countryside! Are they really that dangerous? Well the press would have us believe so, with recent headlines such as, “Alert over rise in killer ticks”, and “The European Invader that’s after your blood”.  Although not quite relatives of Dracula, lurking in every darkened corner, ticks are blood-sucking parasites and they can transmit a range of diseases to people, domestic animals and wildlife.


As a victim of one such disease called Borreliosis (Lyme disease), I am able to speak from personal experience, and with understanding when it comes to the more serious consequences of infection. My disease was not diagnosed or treated promptly and so had the opportunity to become deep-seated within my central nervous system, heart and other organs, causing irreversible tissue damage. It has left me a paraplegic, blind in one eye and partially sighted in the other, and in need of full-time care due to the extensive nature of my health problems. From the bite of a tiny tick, that’s a lot of consequences!


What perhaps resonates with me most powerfully is that these effects were almost certainly avoidable, had I known some basic facts about ticks. Like many people, I had been taught that the most important thing about tick removal was to get the tick to back out itself, so that mouth parts would not be left in the skin. What I didn’t realise was that burning, freezing or smothering a tick in substances such as petroleum jelly, oils and spirits can result in the tick regurgitating infective fluids before it backs out or dies. The current advice from all official bodies in disease prevention is that these methods should not be used.  Pity I didn’t know that when I was zapping ticks off me with a cigarette end!



Ixodes ricinus - the Castor Bean Tick

Ixodes ricinus – the Castor Bean Tick



There are only two safe methods of tick removal:



  1. With a bespoke tick-removal tool (studies have demonstrated the ones designed like a crochet hook to be the most effective, especially with the tiny sub-adult ticks) and the manufacturer’s instructions should always be followed.

  2. With fine-pointed tweezers (grasping the tick as close to the skin as possible and steadily pulling / levering the tick outwards without jerking or twisting. Twisting with tweezers exerts too much pressure on the mouth parts and they may break off, whereas some tick removers are designed to twist without this risk).


Removal with fingers may risk compression of the tick’s body, squeezing out infective fluids, and squashing or scratching off a tick may spill these fluids. Additionally, some ticks carry infective agents which can enter through breaks in the skin.


There are ways that you can reduce the risk of being bitten in the first place. Various insect repellents on the market are effective against ticks, although these parasites are tenacious and nothing is 100 per cent tick proof.


Depending on your chosen activity, wearing the right kind of clothing can lower the risk of being bitten. Light-coloured clothing allows you to see any ticks on you before they have had a chance to get to your skin and attach themselves. Garments with elasticated waistbands and cuffs will also help to deter them and simply tucking trousers into socks or wearing gaiters helps to create a barrier.


Ticks are more often on low vegetation (about 18 inches high) and they wait until a suitable host (animal or human) brushes past and they latch on with special hooks on their legs. They can also drop onto a host from low branches. Then they will wander around looking for a place to feed, so they can be found attached anywhere on the body (including places too personal to mention)!



Despite what has happened to her - Wendy still has a passion for the outdoors

Despite what has happened to her – Wendy still has a passion for the outdoors



Short of wearing a frog suit, it is almost impossible to completely deter ticks.  It is therefore advisable to check yourself as regularly as possible (a shower or bath at the end of the day is a good opportunity for a thorough look). The more you check, the more likely you are to find a tick before it attaches, or soon after. The longer the tick is allowed to feed the more saliva it pumps in to numb the bite area, keep the blood flowing and prevent inflammation. Each drop of saliva potentially carries a range of infective agents and some people can contract multiple infections from a single bite. Of course, you may be happy wandering the countryside in a wetsuit (each to their own), but for most of us it’s preferable to just take simple, sensible precautions and to do a regular tick check.


Had I known about ticks in Britain and Ireland being vectors of disease prior to my becoming infected, I still think I would have been a fully paid-up member of the “it won’t happen to me” and “I’ve been out and about all my life and never had a problem” brigade.  I can understand why people feel this way but, even in the years since I became infected, there has been an increase in the incidence of disease cases, particularly Lyme disease. In Scotland, cases rose from just 28 in 2001 to 605 in 2009 and in England and Wales from 268 to 973 (all figures being the last available and provisional data).


Authorities acknowledge that the recorded data is incomplete.  The Health Protection Agency estimate that an additional 1,000 – 2,000 cases in England and Wales go unrecorded per annum and Dr. Darrell Ho-Yen of Scotland’s Lyme disease testing service believes that the true incidence for Scotland could be ten times the number recorded. Reasons given for the discrepancy between reported and estimated case numbers include wrong diagnoses, tests giving false results, sufferers who weren’t tested, people who are infected but asymptomatic, failures to notify and infected individuals who don’t consult a doctor.


But why is it that when I was diagnosed I didn’t know anyone with Lyme disease, yet now every second person I meet seems to have had or got it, or knows someone who has? Studies have demonstrated various contributing factors. Changes in farming practices and the climate have allowed ticks to complete their life-cycle faster, increasing their population. An increase in host-animal species has allowed their distribution to increase too, while our residential dwellings are ever encroaching on the tick’s habitat, bringing them into close proximity with our recreational spaces.  Another contributing factor is that more people are involved in outdoor pursuits which bring them into contact with prime tick habitat.


At the time I was infected, there wasn’t the availability of information that there is now and even after diagnosis I found my disease to be bewildering and isolating. It was my desire to prevent others from being in the same position that led me to found Borreliosis & Associated Diseases Awareness UK (BADA-UK), along with some fellow sufferers who felt the same. Now in its seventh year, the charity has seen a rise in the appetite for information and the number of people requiring support.


Despite all that has happened to me, my passion for the great outdoors remains. I particularly love taking my camera into the most inaccessible places (for someone confined to a wheelchair, and thanks to a long-suffering husband).


Are ticks the scourge of the countryside? No – they are part of nature’s bizarre and intricate tapestry, but they do need to be given a little respect for they can inflict a nasty bite which may just change your life.



For more information please visit: www.bada-uk.org or write to:


BADA-UK
PO Box 544
Wath upon Dearne
Rotherham
S63 3DW


Biography:
Wendy Fox is a founder member, director and Chair of Borreliosis & Associated Diseases Awareness UK (BADA-UK). She has a background in zoology but became a full-time volunteer for the charity after being medically retired. Wendy was left paralysed from the waist down and partially sighted following an infection with Borreliosis.


If you want to read more about how to beat the bugs – be they midges, ticks or anything else – have a read of the articles in the Outdoor Skills section in our magazine.







没有评论:

发表评论