lördag 4 juni 2016

Are tick bites taken seriously enough?

Last Wednesday afternoon, I spent a couple of hours working in a friend's garden. On Friday morning, ie about 36 hours later, I felt an itching sensation, scratched the area of skin and removed a particle which, on examination, turned out to be a tick. I noticed several other red inflamed areas nearby and took a shower. In the evening I felt the same thing in the groin area and removed another particle which was also a tick, and another again on my back which I never got to look at which might have been a tick, making between two and five tick bites in all.

I went to the local emergency clinic this afternoon (Saturday) and asked the duty doctor for a prophylactic antibiotic. This is apparently against the guidelines which are to wait until a red patch is at least 5 cm across.

The problem with this protocol is that in about 30% of borrelia infections (the tick-borne Lyme Disease) there is no characteristic red patch, so the most advantageous opportunity for treatment is then missed. Also at the early stage, those infected may experience a fever which, however, can be confused with something else. After that the disease can manifest in a diverse variety of conditions which are difficult to diagnose. In the meantime, the infection advances and can affect the nervous system and even enter the brain, again mimicking other conditions including dementia.

It seems that if treatment with antibiotics begins sufficiently early, at the latest during the fever stage, then the patient will recover completely. After that, treatment becomes more difficult and eventually, the organism is well entrenched and hidden out of reach of antibiotics.

There is another sinister side to this infection: people may seem to have recovered but might not have. In this, Lyme disease seems to resemble one caused by another member of the same Spirochaeta family of bacteria: Treponema pallidum, the organism which causes syphilis and yaws, and another which causes Weil's disease. There is a poem about syphilis called, in this version,
"The Man from Bach Bay"
There once was a man from Bach Bay,
Who thought syphilis just went away;
He thought that a chancer
Was only a canker
Derived from lascivious play.
But now he has acne vulgaris,
(The kind that is rampant in Paris)
It covers his skin,
And his friends all ask where his hair is.
He has pains. in his head and his knees,
His sphincters have gone by degrees;
Paradox incontinence
With all its conoomitance
Bring quite unpredictable - .
With sensations progressing in number,
His aorta's in need of a plumber;
His heart is cavorting
His wife is aborting
Without doubt he's developed a "gummer".
There is more to his terrible plight,
His pupils won't react to light;
Along with his tabes
And saber-shinned babies,
He also has gun-barrel sight.
Though treated in every known way,
His spirochetes grow day by day;
He's developed paresis
Converses with Jesus
And thinks that he's Queen of the May.
Borrelia is less aggressive than syphilis but infections are debilitating and degrade the health of many of the sufferers. Faced with such a risk, and in the absence of a vaccine, one would have thought that the health authorities would lay down stricter guidelines for prevention, including prophylactic treatment of those who might have become infected. That prophylactic antibiotics are effective has been demonstrated by this study here carried out in 2001, which concluded that "A single 200-mg dose of doxycycline given within 72 hours after an I. scapularis tick bite can prevent the development of Lyme disease."

So how seriously should we take this?
A balance must be struck between panic reactions, paranoia and nonchalance. Borrelia is not AIDS, or syphilis as it was before antibiotics. Most authorities seem to agree that tick bites only rarely result in infection but that it can seriously damage people's health. I wonder, too, if infection is as rare as is claimed. I know, personally, two people whose condition is untreatable (one of them a doctor), another three who have been infected and had to receive treatment, and another whose mother was badly affected.That is quite a lot of people considering the small size of my circle of acquaintances.

Even if only, say, 1% of bites result in infection, then with ten bites in a year there is a 10% chance of infection; of course the odds do not increase with successive bites. There is an analogy here with unprotected casual sex. The chances are that you will get away with it once but sooner or later you will get something nasty. Matters are further complicated by the fact that, as mentioned earlier, the initial bite may not be noticed, that the characteristic red spot does not always appear, and that the fever may not develop, or could be mistaken for something else, such as influenza.

It is a increasing problem, as the areas infested with ticks are constantly spreading, partly due to climate change. This year is particularly bad due to the mild winter. It is now in urban areas. I was attacked far from the zones marked on last year's map as liable to be infested, which is why I had taken no precautions.

Perhaps the protocols need to be changed so that treatment is given at the earliest possible opportunity. Since the reservoir of disease is in the wild population, there is little the risk of antibiotic resistance developing. However, the presence of the disease in animals also raises questions about whether it can be transmitted by contact with infected animals used for food, for instance in slaughter, butchery or preparation?

In the absence of anything better, anyone who thinks they may have become infected might take advantage of the principles behind the old "malaria treatment" for syphilis: the organism is killed at 41 degrees. One approach to Lyme disease is what is called hyperthermia ie raising the body core temperature artificially to simulate a fever, for example by spending time in a steam room. Eating plenty of garlic is also reputed to keep the creatures away.

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