“…The most commonly isolated bacteria belong to the genera Streptococcus , Neisseria , Haemophilus , Moraxella , Staphylococcus , Corynebacterium , Propionibacterium , Prevotella , and Porphyromonas [ 1 , 2 , 3 ]. Among them, the most common causes of infections are: Streptococcus pneumoniae , S. pyogenes , Haemophilus influenzae , Moraxella catarrhalis , and Staphylococcus aureus [ 3 , 4 , 5 , 6 , 7 ]. The imbalance in the URT microbiota is associated with the increase in the number of invasive pathogenic bacteria, leading to inflammation and infection.…”