Tetracycline resistance in Moraxella catarrhalis clinical strains isolated in Poland.

Moraxella catarrhalis is considered an important, exclusively human respiratory tract pathogen which, along with Streptococcus pneumoniae and Haemophilus influenzae, is classified as one of the most frequent bacterial etiological factors causing upper respiratory tract infections. In this manuscript, we report the existence of five tetracycline-resistant M. catarrhalis strains with confirmed presence of tetracycline resistance tetB gene. The strains were isolated from children under the age of three with signs of upper respiratory tract infections. Our research also investigated the occurrence of virulence genes in these strains and involved the analysis of drug resistance to five antibiotic groups. It is the first description of clinical strains with confirmed presence of drug resistance tetB genes isolated in Europe.