Study of the specificity of the spread of community-acquired pneumonia in the Lipetsk region and the relationship with seasonal gains in the incidence of influenza and acute respiratory viral infections

Introduction. Community-acquired pneumonia (CAP) remains a significant health problem requiring attention due to its high prevalence and difficulties in etiological diagnosis.

The purpose is to study the epidemic process of CAP in the Lipetsk region over 2011–2024. and assessing the relationship with the incidence of influenza and acute respiratory viral infections.

Materials and methods. Analytical, logical, epidemiological, and statistical methods were used. Data from federal statistical reporting forms No. 1 and No. 2 of the Federal Service for Supervision in Protection of the Rights of Consumer and Man Wellbeing (Rospotrebnadzor) for 2011–2024, calculated per 100 thousand population, were used. Statistical processing was carried out using variation statistics methods in Microsoft Excel (2010). Correlation was assessed using the Spearman coefficient.

Results. The CAP incidence in the total population of the region increased by1.7 times (from 450.5 per 100 thousand in 2011 to 800.8 in 2024); the long-term average was 604.23. The maximum was recorded in 2020 (1194.78). The correlation of CAP with influenza and ARVI was weak and statistically insignificant. The structure of morbidity was dominated by adults (70.3%), among children — groups of 7–14 years (32.2%) and 3–6 years (26.3%). In 2023, there was an increase associated with the circulation of Mycoplasma pneumoniae. Before the pandemic, M. pneumoniae and other bacteria predominated; in 2020–2022 SARS-CoV-2 dominated; Since 2023, bacterial agents have become active again. About 50% of cases remained etiologically undeciphered (in 2024 — 72%).

Limitations. When studying the CAP incidence in the Lipetsk region, an analysis of data from official statistical reporting forms No. 1 and No. 2 “Information on infectious and parasitic diseases” of Rospotrebnadzor for 2011–2024 for the Lipetsk region was carried out.

Conclusions. The epidemiological situation regarding CAP in the region remains unstable. It is necessary to improve diagnostics with the introduction of modern laboratory methods and increase the level of etiological decoding to optimize prevention and reduce mortality.

Compliance with ethical standards: the study does not require the submission of the conclusion of the biomedical ethics committee or other documents.

Contribution of the authors:
Korotkova T.S. — The concept and design of the study, writing text, compiling a list of literature;
Trukhina G.M. — editing, approval of the final version of the article;
Reshetova A.A. — collection and processing of material, writing text, statistical processing, compiling a list of literature;
Savelyev S.I. — editing, approval of the final version of the article, responsibility for the integrity of all parts of the article;
Tabolina E.Yu. — statistical processing of material, editing;
Ushakov S.A. — approval of the final version of the article, responsibility for the integrity of all parts of the article.
All co-authors approved the final version of the article.

Funding. The study did not have sponsorship.

Conflict of interests. The authors declare the absence of a conflict of interest.

Received: October 6, 2025 / Accepted: April 24, 2026 / Published: July 28, 2026

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