Post-COVID Immunological Disorders as a Factor of Increased Susceptibility to Secondary Bacterial Infections

This paper presents a systematic analysis of the impact of COVID-19 on the development of prolonged immunological dysfunction. The study is based on a retrospective review of data from over 25,000 patients between 2021 and 2025. It was found that SARS-CoV-2 leads to a state of «immunological debt», characterized by T-cell exhaustion, chronic systemic inflammation, and profound dysbiosis of the mucous membranes. The study identifies these disorders as key predictors of the increasing incidence of invasive bacterial infections, particularly those caused by Streptococcus pyogenes, Pseudomonas aeruginosa, and Haemophilus influenzae. The authors analyze trends in the increasing antibiotic resistance of secondary flora and highlight the multisystemic nature of Long COVID, which includes cognitive impairment and reduced quality of life in convalescents. The findings emphasize the need to update empirical therapy protocols and develop multidisciplinary rehabilitation strategies.

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