Lyme disease, or Borrelia burgdorferi, is transmitted, as you said, by small deer ticks sucking blood of the host to reproduce. While sucking blood it can transfere this Borrelia bacteria that can cause neurological and cardiological diseases.
If you get the tick out of the skin within 24 hrs, you propably don`t get the infection. If you get the red rash with a clear center, you can be treated by penicillin or tetracycline - with good results! Both my children has had this infection (the rash) and got treated with antibiotics. They have no signs of the Lyme disease now (6 mnds and 2,5 years after).
You can also be diagnosed after the rash has disappeared; and the antibiotic treatment will still help (a couple of weeks to months after the biting).
We have a lot of these tics here in the south west coast of Norway, and we have discovered that the best protection is garlic! If the blood "smells" garlic, the ticks will not bite (just as a vampire

).
The reason why there are so much ticks now, is due to environmental changes! There are much warmer winters now, so the ticks are able to survive. If we have more than -20 degrees Celcius for over a week, the tcks will dye, and so will the bacteria within them...
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