PERTURBATIONS IN THE MICROBIAL BALANCE ASSOCIATED WITH ACUTE RESPIRATORY VIRAL INFECTIONS AND ANTIBIOTIC THERAPY

To determine the characteristics of bacterial colonisation of the nasopharynx in patients according to history of acute respiratory viral infection (ARVI) and use of antibiotic therapy within the previous three months. The study was conducted at the Department of Microbiology, Virology, and Immunology of I. Horbachevsky Ternopil National Medical University. In a prospective clinical trial, 57 patients were divided into three groups: Group I - without ARVI and antibiotic therapy; Group II - after ARVI, without antibiotic therapy; Group III - after ARVI with antibiotic therapy. Classical bacteriological methods were used to assess the nasopharyngeal microbiota. Statistical analysis was performed using one-way ANOVA and Tukey HSD test. Group III showed a significant decrease in the concentration of Staphylococcus spp., Corynebacterium spp., and Streptococcus spp. (p<0.05), along with an increase in Staphylococcus aureus levels and the emergence of Streptococcus pyogenes. Group II demonstrated intermediate values between Groups I and III, indicating the impact of both ARVI and antibiotic therapy on the nasopharyngeal microbiota. A history of ARVI leads to statistically significant alterations in the nasopharyngeal microbiocenosis. Antibiotic use is associated with more profound disturbances of the normal microbiota and an increased carriage of Staphylococcus aureus, which may indicate a risk of developing antibiotic resistance.