Encounters of the Tick Kind
About a week ago I ran the Komen 5k Race for Breast Cancer. It’s a BIG race, 11,000 people participated this year. In the afternoon I noticed a rather large bug bite on my neck. It was a little itchy, and very big and red, but nothing too out of the ordinary.
Over the week it began to go down, but round about Thursday I noticed that it was red again, and kind of had a rash around it. I thought maybe it was a spider bite or something, but I would be fine in a few days. Then Friday it was a little worse. I happened to mention it and showed the bite to my friend Nancy. Her eyes got very big, and she told me to get to the doctor NOW.
I went to the doctor, who took one look at me and declared that I had a textbook case of Lyme Disease. I kind of laughed it off at first, but it can get very serious if left untreated. Thankfully, we caught it early, and hopefully I’ll be fine with a few weeks of antibiotics.
Lyme disease is named after the town where it was discovered, in Lyme, Conneticut. It is the most commontick-borne disease in North American and Europe, with about 20,000 people infected per year. It is prevalent in the northeastern US and the area west of the Great Lakes, so it’s actually pretty rare that I got it in North Carolina. The disease is actually called borreliosis, because it is caused by bacteria in the genus Borrelia. In the east, the bacteria are transmitted to humans from bites by deer ticks, while on the pacific coast, you get Lyme disease from blacklegged ticks (apparently they are the same thing, Ixodes scapularis, but called different things). Lyme disease is transmitted most often in the nymph stage of the tick, which is SO tiny that I’m not surprised I missed it (visual courtesy of Mcgill University).
The genus Borrelia (the species in the US is Borrelia burdorferi), is a spirochete bacteria, which people always say looks like a coiled spring, but which I think looks like a piece of badly permed hair. The cool thing is that they move by endoflagella, which are axonal filaments that rotates the spirochete around (picture below courtesy of the CDC).
The bacteria typically get transferred to the tick vector when the tick feeds on a small mammal while the tick in the larval or nmyph stage, usually the white-footed mouse (for a blog post on the ecology of Lyme Disease, try here, it’s a cool article on how population densities of animals and plants over a two year period can affect whether or not you get Lyme Disease! Who knew that my case of Lyme depended so heavily on acorns and white-footed mice.)
Once the tick is infected, the bacteria remain in the tick while the tick goes from larva to nymph and from nymph to adult. During the nymph or adult stage, the tick feeds on other mammals, transmitting the bacteria in the process. The most common adult tick food is the white-tailed deer, which now has become a reservoir for Lyme disease in some areas. The whole life cycle of the tick takes about two years.
Once it gets in your body, the bacteria can take anywhere from a few days to a month to incubate, before it produces the classic pattern around the site of the bite. This pattern looks like a circular halo around the area of the bite, called an erythema migrans . The halo can reach up to a foot across, and looks kind of like a bull’s eye. Then other symptoms start (I’m having these right now and it’s not very fun), including swollen lymph nodes, fatigue, chills, fever, headache, and severe muscle and joint pain.
If it goes untreated, people with Lyme disease may develop chronic Lyme disease, which is pretty much untreatable, and results in severe arthritis episodes, shooting pains, and loss of short term memory. Not only that, but apparently chronic Lyme disease can cause episodes of psychosis, complete with panic attacks, delusions, and symptoms that people misdiagnose as schizophrenia or bipolar disorder.
Luckily, Lyme disease is usually caught very early (it’s hard to miss an enormous bull’s eye rash), and antibiotics can usually take care of the problem. The usual treatment in adults is a few days to a few weeks with doxycycline, which is a common antibiotic. Unfortunately, the side effects of nausea and skin sensitivity can be no fun at all. You can’t take the pill anywhere around a meal, because that slows the absorption. So when you take them on an empty stomach, brace yourself. And wear a LOT of sunblock, doxycycline makes your skin very sensitive to sunlight.
So the moral of the story is: watch for ticks! Apparently they can also live in trees. And if you see anything like a halo pattern, go to the doctor immediately! I’ve got photo documentation of my own bite, if I can get it on the web somewhere I’ll put it up.
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