Epidemiological features of acute enteric infections in healthcare settings in the context of shifting dominant pathogen variants

Objective. To study the epidemiological features of acute enteric infection (AEI) outbreaks in healthcare settings in the context of shifting dominant pathogen variants and to provide recommendations for the application of modern epidemiological practices in outbreak investigations. Materials and methods. A retrospective analysis of 21 AEI outbreaks in healthcare settings, involving 416 affected individuals, was conducted. The analysis utilized data from Form No 23, outbreak epidemiological investigation reports, and statistical analysis methods. Results. 80.95% of outbreaks in healthcare settings were caused by enteric viruses (norovirus, rotavirus, enterovirus), primarily transmitted via fomites and contact routes. 14.3% were caused by bacteria (Salmonella enteritidis, Shigella sonnei) with foodborne transmission. Outbreaks of bacterial etiology predominantly affected patients over 18 years of age, occurred during the summer months, were characterized by a large number of affected individuals (Me = 81), a high proportion of severe clinical forms (4.6%), and a high index of spread within the outbreak (79.3). For viral outbreaks, the spread index was 17, and the number of cases during outbreak propagation was Me = 8 (Q1–Q3: 6.5–10.5). A direct correlation was established between outbreak duration and the number of affected individuals (an increase of 2.7 persons per day). Conclusion. The investigation of AEI outbreaks in healthcare settings necessitates novel epidemiological practices. These practices should be founded on a comprehensive understanding of the characteristics and epidemic potential of the pathogens involved, and must employ molecular genetic methods for accurate etiological diagnosis and pathogen identification. Key words: outbreak-related morbidity, healthcare settings, epidemiological practices, acute enteric infections