Lyme borreliosis is the most common animal-to-human infection worldwide and also the most common tick-borne bacterial disease. The causative agent of the disease is a highly motile, wave-shaped bacterium classified in the Borrelia genus, a spirochete approximately 15 micrometres long and 0.2 micrometres wide.
Ticks belonging to the Ixodes genus transmit Borrelia burgdorferi sensu lato (the collective name for all Borrelia burgdorferi subspecies) to humans.
In Europe, at least three species cause disease in humans: Borrelia afzelii, Borrelia burgdorferi sensu stricto (the Lyme pathogen in the narrower sense, identified by Willy Burgdorfer) and Borrelia garinii.
It has been recognised that all three pathogenic species are associated with a clinical picture:
• Borrelia burgdorferi sensu stricto: arthritis
• Borrelia garinii: neurological symptoms
• Borrelia afzelii: skin symptoms, joint diseases – and not just inflammation of the large joints. The Carpathian Basin, the most common pathogen in Central Europe
In Central Europe, borrelia can enter the body after a tick has been attached for less than 4 hours, although the average attachment time is 24 hours. In addition, the infection can spread throughout the body via the rapid bloodstream. According to the latest data, the pathogen can enter the connective tissue of the skin from the very first moment and cause local infection as it spreads.
Ticks bite people most often on Saturdays and Sundays, which confirms the fact that Lyme borreliosis is primarily a leisure-related infection. The location of tick bites on the human body depends on contact with the ground: in children, more than 75% of bites are found on the head and neck, while in adults, most bites occur on the lower limbs, in the groin, between the buttocks and below the lower abdomen. During military exercises, conscripts who come into contact with the ground mainly suffer tick bites on their upper limbs.
According to a study in Bavaria, 16% of the total population is affected by tick bites once a year. On average, 3% of the population develops Lyme borreliosis after a tick bite.
The annual incidence of Lyme borreliosis is highest in Central European countries.
However, the uncertainty surrounding the reliability of data on Lyme borreliosis cases can also be attributed to the difficulty of proving early symptoms.
