Lyme borreliosis is caused by bacteria which can be present in the ticks body. In 1975 the first cases of borreliosis were reported in Lyme, Connecticut. Sometimes a ring shaped reddish bruise can be seen around the bite.
It has happened that people been walking around several years without understanding the reason to their disease trouble was a tick bite. Treated with antibiotics.

The group of bacteria known as Ehrlichia has been known in veterinary medicine since 1935. In 1954 the first case of Ehrlichiosis on a human was described in Japan. The main symptoms are high temperature, head and joint ache. Liver and heart can be attacked. Treated with antibiotics.

TBE, from Tick-Borne-Encephalitis. One of ticks transmitted encephalitis caused by a virus. After being contaged by the TBE-virus, flue-like symptoms will be seen after a couple of weeks. Most people get well after a while. In about 1/3 of the cases the virus spreads to the brain, which can cause severe trouble. Vaccine is available.

Babesiosis is caused by a blood parasite which destroy the red bloodvessels. There are at least 70 different types of babesia in the world, of which at least two can infect humans.