[History of the study, epidemiology of the disease and characterization of Borrelia burgdorferi infection].

From the beginning of the twentieth century interest in tick-borne borreliosis continues to be an important diagnostic and therapeutic problem. In 1977, in Lyme and Old Lyme, Cunnecticut, in the United States, arthritis and skin lesions were described in 12 children, which were associated with tick bites. The name of the place was called a syndrome of Lyme disease. Dr Willy Burgdorfer observed microaerophilic Gram-negative bacteria (Spirochetes) with a diameter of 0.3-0.5 µm and a length of about 20-30 µm, which were isolated from the tick colon. Lyme disease (borreliosis) is the most common tick-borne disease in the world. In Poland, most cases of Lyme disease occur between May and November, and more than 80% of cases are found in June and July during the nymph ticks feeding. The northern part of the country is considered endemic. The reservoir of bacteria is about 300 different species of mammals. These are mainly rodents of the norovirus and mouse family, and live deer, deer and wolves, as well as some species of birds. Ticks are infected with Borelia burgdorferi through the blood of infected animals. However, adult ticks are infested with Lyme spirochetes, depending on the region of the country. It infects 5-20% nymph and 15-40% adult individuals. The sequence of the Lyme disease spirochetes reveals a number of interesting traits. Classical virulence factors have not been isolated and therefore it is suspected that the vertebrate does not contain it in relation to mammals. However, a number of lipoproteins have been defined and some of them may be factors contributing to the innate immune system.