The bite of a humble tick can trigger a truly nasty illness. Expert advice to help you avoid Lyme disease
In 1971 there was an outbreak of what appeared to be arthritis in the children of Old Lyme, Connecticut. Medics identified an antibiotic-treatable microbe (akin to syphilis spirochetes) and realised it was spread via tick bites. It became know as Lyme disease; more than 20,000 cases are reported in the US each year.
The disease has actually been known since 1909, when it was first recorded in Sweden. The disease has almost certainly been around for centuries, certainly on three continents and probably wherever Ixodes – ‘hard’ ticks – are found.
In regions where Lyme disease exists, it is estimated that only 2-3% of those bitten by a tick develop an illness. Ticks need to be attached for at least eight hours for Lyme disease to be transmitted.
It is probably widespread throughout the world. In temperate habitats where it has been studied most carefully, it is usually found where sheep or deer graze among trees and bracken. Lyme-carrying ticks like border habitats: between woods and meadows, and especially sparsely wooded forest paths. It is found across Europe and in the Americas.
People who are at most risk of picking up a tick are those who are pushing through undergrowth and bushes as they walk, and those who are camping in regions where deer or sheep graze. Tick bites are commoner where sheep aren’t dipped. Young ‘seed ticks’ can get onto campers in large numbers and are hugely irritating. They may need to be scraped off with a knife or fingernail.
I think of ticks as sesame seeds on short little legs. They are slow moving but determined. Once they have fed they swell to something looking like a red kidney bean.
Ticks are amazingly good at crawling over your skin without you feeling them. They can also fast for ten years between meals. However, once attached, they are happy to stay feeding for days or even weeks.
Hard ticks are adept disease transmitters because, given the chance, they cement themselves in place and feed for days. They are distinguished from less-harmful ‘soft’ ticks by the hard shield at the front of their bodies.
Sometimes you find a tick firmly attached to you. If you are unlucky enough to be infected, seven to ten days after you’re bitten a slowly enlarging, non-itchy bull’s-eye or target-shaped red patch, ring or weal appears in most (70%) people infected. It spreads to a diameter of about 15cm over a couple of weeks, and may persist for months or disappear after a few weeks.
Other common symptoms (80% of cases) are aching joints, fever, muscle aches and headache.
Untreated, the disease slowly progresses, developing into a serious illness that can affect the heart, nervous system and brain. Antibiotics are effective as long as they are given early.
A vaccine against the American strain of the disease was developed and licensed in the USA. It was 76% effective (ie, not very), and was withdrawn in 2002 because the vaccine itself appeared to cause arthritis. At present there is no vaccine and no protective pills.
The only preventative strategy is to avoid tick bites. Wear long clothes with trousers tucked into socks and, even better, proof your clothes by spraying them with permethrin. For about £6 you can spray one adult outfit. Once sprayed, the outfit should be left to dry; the clothes then lose their odour to humans but repel ticks and other biters for two weeks.
The other important action is to check yourself for feeding ticks at the end of each day (they like to attach to sensitive regions) and remove any as soon as you can – this should give absolute protection from Lyme disease. Ticks can settle down and feed inside the ear, though, so children should be checked carefully.
Also check for new swellings in the groin, armpit or other cosy spots when you bathe each evening.
It is important to stay cool during removal. Manoeuvre your finger and thumb on either side of the mouthparts of the tick, as close to your skin as possible, and pull steadily away. If you are a nail-biter with no fingernails this may be more challenging. Flood the wound with spirits or strong antiseptic if you have it. If you experience any symptoms after a tick bite, see a doctor.
“I think I caught Lyme disease in Sweden in August 2007, though I didn’t get the typical red bite mark. My knees and hands hurt, and I couldn’t get up from the sofa easily.
"It took a year before it was diagnosed; I’ve since learned it’s a difficult bug to spot –
my local GP didn’t even know what Lyme disease was.
"Lyme Disease Action thinks many people are misdiagnosed with ME or chronic fatigue syndrome. Because treatment wasn’t started until August 2008, I’ve now got chronic Lyme disease with Lyme arthritis. I don’t have the same energy I used to and can’t overdo things.
"If you walk in long grass where deer or sheep may have roamed, cover up and check for ticks immediately post-walk. It’s estimated that one in three ticks is infected.
If you find a tick, put it in a jar and take it to your GP pronto. Ask them to give you a four-week course of antibiotics and you should be fine. Don’t let them fob you off!”
Sue Ockwell, MD of Travel PR