Clinical characteristics and co-infection analysis of influenza a virus in pediatric respiratory infections: a study based on tNGS technology.

OBJECTIVE

Influenza A virus (IAV) represents a significant etiological agent of respiratory infections in pediatric populations. The primary objective of this research was to evaluate the infection status and clinical manifestations associated with IAV in these pediatric patients.

METHODS

From April 2021 to December 2024, 10,310 pediatric inpatients diagnosed with respiratory infections were enrolled at Guangxi Zhuang Autonomous Region Maternal and Child Health Hospital. Pathogen screening was systematically performed on biological specimens using targeted next-generation sequencing (tNGS) technologies.

RESULTS

Among 10,310 pediatric inpatients with respiratory infections screened by tNGS, 325 cases (3.2%) demonstrated IAV detection, predominantly distributed among preschool-aged children (3-5 years) and adolescents (5-11 years), with males predominating (male: female ratio 1.5:1). Monoinfection was observed in only 9 cases (2.8%), while 316 patients (97.2%) exhibited co-infections, primarily manifesting as IAV-bacterial-viral (97 cases, 29.8%) and IAV-bacterial (91 cases, 28.0%) co-infection patterns. Comprehensive pathogen profiling identified 41 distinct co-pathogens, with Haemophilus influenzae, Streptococcus pneumoniae, and Mycoplasma pneumoniae being the most common. Clinically, 33.2% developed respiratory complications (n = 108) and 41.2% extrapulmonary manifestations (n = 134), requiring median hospitalization of 6 days (IQR 5-8). Critical care needs included respiratory support in 20.6% (n = 67) and ICU admission in 4.6% (n = 15), underscoring the substantial disease burden associated with IAV co-infections in pediatric populations.

CONCLUSION

This study delineates critical epidemiological and clinical patterns of pediatric IAV infections. A striking 97.2% of IAV-positive cases exhibited polymicrobial co-infections, necessitating implementation of comprehensive diagnostic panels. Clinically significant extrapulmonary complications developed in 41.2%, mandating vigilant multi-system monitoring beyond conventional respiratory surveillance. The 4.6% ICU admission rate, coupled with median hospitalization of 6 days (IQR 5-8), underscores the substantial healthcare burden imposed by IV-associated co-infections in pediatric populations.