Comparative Analysis of Bacterial Microflora Isolated from Adult Pneumonia Inpatients and Hospital Objects in the Amur Region

Abstract

Background: The COVID-19 pandemic has exacerbated the problem of healthcare-associated infections and worsened the situation with the hospital spread of antibiotic resistant strains potentially inducing nosocomial infections. Objective: To compare bacterial microflora isolated from adult pneumonia inpatients and hospital objects and to assess the risk of hospital-acquired infections in the Amur Region. Materials and methods: The study was conducted in a multidisciplinary and a “COVID” hospital hereinafter referred to as Hospitals 1 and 2, respectively. Parallel bacteria culture testing of 519 sputum samples from 284 inpatients and 486 wipe samples collected weekly during 12 weeks in both hospitals was carried out using a classical method. AutoSCAN-4 and Vitek® 2 Compact 30 analyzers were applied to identify pathogens and determine their antimicrobial susceptibility. Results: Along with the detection of pathogenic bacteria in 33.8 % of hospitalized patients with pneumonia, we found pathogens in 23.3 % and 12.4 % of wipe samples from Hospitals 1 and 2, respectively, and established that the proportion of Gram-negative bacteria in them was 44.9 % and 15.4 % while the share of multidrug-resistant strains was 32.7 % and 3.8 %. The significant differences observed can be attributed to a more stringent disinfection regime in Hospital 2. The structure of multidrug-resistant Gram-negative bacteria was noted for a high proportion of carbapenem-resistant organisms isolated from both sputum (20.0 %) and wipe (38.9 %) samples. Conclusion: Our monitoring results helped define the composition and ratio of bacterial pathogens isolated from pneumonia cases and hospital objects. A wide range of pathogens, including those resistant to antibiotics, often detected in wipe samples and their accumulation over time indicate the potential hazard of the hospital environment posing an increased risk of hospital-acquired infections.