Epidemiological patterns of respiratory infections in children in the post-pandemic period: the role of multiplex PCR in the rapid differentiation of viral and bacterial infections
DOI:
https://doi.org/10.13112/pc.1190Keywords:
Respiratory Tract Infections; Coinfections; Clinical Decision-Making; Croatia; Pathology, Molecular; Multiplex Polymerase Chain ReactionAbstract
Introduction: Acute respiratory infections are the most common illnesses in the pediatric population. The clinical presentation of viral and bacterial infections often overlaps, making differentiation based on symptoms challenging. Modern molecular diagnostics enable the simultaneous detection of multiple respiratory microorganisms with rapid turnaround times. The aim of this study was to determine the frequency and distribution of respiratory microorganisms among children and adolescents.
Methods: The study included all symptomatic outpatient patients aged 0–18 years who presented for testing between January 1 and December 31, 2024, at the Teaching Institute of Public Health of the Split-Dalmatia County in Split, using multiplex real-time PCR for the detection of 13 respiratory pathogens.
Results: Of 7,516 respiratory panels performed, 5,264 (70 %) were positive. As some panels were positive for two or more microorganisms, a total of 6,690 positive results were recorded, predominantly viral (85.4 %). Monomicrobial infections predominated (80.5 %). Rhinovirus was detected in 42.8 % of positive results, followed by influenza A virus (10.5 %), parainfluenza virus (8.8 %), respiratory syncytial virus (8.7 %), Mycoplasma pneumoniae (6.1 %), Bordetella pertussis (4.8 %), adenovirus (4.8 %), human metapneumovirus (4.5 %), SARS-CoV-2 (4.1 %), Chlamydia pneumoniae (3.7 %), influenza B virus (1.2 %), Bordetella parapertussis (0.1 %), and Legionella pneumophila with a single positive result. Coinfections were detected in 19.5 % of panels. The highest proportion of positive panels was recorded in the first quarter of the year (46.3 %).
Conclusions: Although viral pathogens are the most common across all age groups, an age-adjusted clinical approach is required. In infants and preschool-aged children, viral etiology should be the primary diagnostic consideration, whereas in school-aged children and adolescents, bacterial pathogens should also be considered, particularly in cases of prolonged or atypical symptoms.
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Copyright (c) 2026 Anamarija Jurčev Savičević, Vanja Kaliterna, Duje Rakić, Vinko Zoranić, Marta Righi, Nora Josipa Savičević
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