Lyme disease in Poland in 2021.

Abstract

Lyme disease, a zoonosis transmitted by vector (by ticks), may manifest itself in several different forms, such as: erythema migrans, osteoarticular or neuroborreliosis. Infection occurs when an infected common tick (Ixodes ricinus) feeds. Lyme disease is seasonal due to the cycle of tick activity throughout the year. The aim of the study was to assess the epidemiological situation of Lyme disease in Poland in 2021 compared to the situation in previous years. To assess the epidemiological situation of Lyme disease in Poland, data sent to NIPH NIH - NRI by the Voivodeship Sanitary-Epidemiological Stations and published in the annual bulletin: "Infectious diseases and poisonings in Poland in 2021" were used. In 2021, 12,500 cases of Lyme disease and 411 hospitalizations were registered, which means a decrease in the number of cases by 3.4% and a decrease in hospitalizations by 10.5%. The number of cases was similar to 2020, and Lyme disease cases did not return to the pre-COVID-19 pandemic level (approx. 20,000 cases per year). The quarterly distribution of cases remained unchanged, with cases occurring most frequently in Q3 and least frequently in Q1. The impact of the COVID-19 pandemic on the number of reported Lyme disease cases was still noticeable, the number of recorded cases was lower than in the first pandemic year. The distribution of cases in quarters retained the seasonality characteristic of Lyme disease.