Ticks carry unpleasant and dangerous diseases. They are not insects, but they belong instead to the arachnid family. In our latitudes there are about two dozen species of ticks, of which eight are of medical importance. The castor-bean tick (Ixodes ricinus) is most commonly responsible for transmitting diseases to humans.
During each stage of their development ticks have to consume blood. Ticks do not have wings and they cannot jump. Instead to find a donor they settle on grass, ferns or the underside of leaves and bushes. They can wait for several months for a suitable host. If they detect a host, they drop on to it and find a convenient place to suck blood. On humans they prefer moist and warm areas such as the armpits or genital area. Their barbed proboscis unfolds like an umbrella, after biting, to anchor the tick to the skin. If undisturbed they will feed for up to nine days. Once full of blood the tick, several times larger then drops off the host.
The bite itself is usually unnoticeable, since pain-killing secretions are released. Often the site of the bite is only slightly red. However, the tick’s saliva and its excrement can transmit germs.
Ticks are carriers of tick borne encephalitis (a viral disease), which only occurs endemically in certain areas. However they also carry borreliosis a much more common bacterial disease in all regions with temperate climates. If a circular rash appears round the tick bite, which increases in size, it is imperative to consult a doctor.
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