Reidentification and determination of drug susceptibility of Corynebacterium diphtheriae and Corynebacterium ulcerans strains isolated from clinical samples in 2023 in Poland

Despite the fact that the last cases of fully-symptomatic diphtheria were recorded in Poland in 1996 and 2000, infections caused by non-toxin-producing strains of Corynebacterium still occur. According to the epidemiological reports from ECDC in the second half of 2022, there was an increase in the number of diphtheria cases in European Union countries. As a result, the current issue becomes the appropriate preparation of microbiological laboratories for the diagnosis of Corynebacterium microorganisms.