Epidemiological characteristics analysis of childhood influenza A virus infections in Hebei, China (2020-2024).

OBJECTIVE

To analyze the epidemiological and infection characteristics of childhood influenza A virus infections in Hebei, China, from 2020 to 2024, and to provide a basis for influenza prevention and control among children.

METHODS

A retrospective analysis was conducted on epidemiological and clinical data of children with influenza A virus infection who were hospitalized in Hebei Province from January 2020 to December 2024. Clinical specimens were analyzed using nucleic acid extraction reagents with automatic extraction on the Smart LabAssist-32 nucleic acid extractor. A 13-pathogen multiplex PCR detection kit combined with the GeXP multiplex gene expression analysis system was used for testing.

RESULTS

A total of 298,810 specimens from children with upper and lower respiratory tract infections were collected. Among which 60,928 specimens were positive for influenza A virus (detection rate: 20.39%). The infection rate was highest in 2024 (23.03%) and lowest in 2020 (13.57%). The annual positive detection rates of influenza A virus in Hebei from 2020 to 2024 were 13.57%, 16.97%, 19.95%, 20.41%, and 23.03%, respectively, with statistically significant differences (P < 0.05). The positive detection rate was significantly correlated with seasons, peaking in winter (29.04%) and reaching the lowest in spring and summer (5.4%). Mixed infections were detected in 16,049 specimens (26.34%), mainly involving rhinovirus, respiratory syncytial virus (RSV), and Mycoplasma pneumoniae (MP).

CONCLUSION

Pediatric influenza A virus infections in Hebei Province exhibit a clustered age distribution, pronounced seasonal variation, and a high co-infection rate. Enhanced surveillance and protective measures should be targeted toward children aged 1-5 years and prioritized during the winter season. This study provides important scientific evidence for optimizing influenza prevention and control strategies, clinical diagnosis, and treatment.