Use of probiotics in the prevention of respiratory infections in childhood

Abstract

Introduction: Acute respiratory infections are diseases that affect any segment of the respiratory tract within a period of up to 7 days. In childhood, their relevance is due to their high frequency and, at times, unfavorable outcomes, such as hospitalization and death. Recent studies have investigated the use of probiotics in preventing these infections, evaluating the benefits of immunomodulation by these live microorganisms in the host. Objective: To evaluate the effectiveness of probiotics in preventing respiratory infections in children. Methods: A systematic review was conducted, gathering randomized clinical trials. Using platforms such as Scopus, PubMed, Scielo, Clinical Trials, and Embase, in May 2024, filters were applied and data that answered the question "Is the use of probiotics or similar products associated with a reduced risk of respiratory tract infections in children?". A total of 1,157 articles were narrowed down to 33 articles included in the study. Trials emphasizing treatment, symptom reduction, and/or other effects contrary to the focus were excluded. Results: In the 33 articles reviewed, we observed whether there was a decrease in respiratory infection episodes. The results varied depending on the type of probiotic used, the microorganism, the dose, the route of administration, and the duration of use. Some studies demonstrated successful prevention, while others did not. Conclusion: Considering numerous influencing factors (age group, atopy variables, and recurrent infections), conflicting results were obtained. The use of probiotics in the prevention of respiratory infections remains controversial, requiring studies with methodological rigor.