OBJECTIVE To investigate the epidemiological characteristics of human bocavirus （HBoV） in hospitalized children with respiratory infections in Ningbo, and to provide references for the prevention and control of HBoV infection.

METHODS Throat swab specimens were collected from children hospitalized for respiratory infections at the Affiliated Women and Children's Hospital of Ningbo University between Jul. 2019 and Dec. 2025. Multiplex reverse transcription-polymerase chain reaction （RT-PCR） and capillary electrophoresis were employed to detect 11 non-bacterial pathogens, including human bocavirus, influenza virus and respiratory syncytial virus. Clinical data of the children were also collected for statistical analysis.

RESULTS A total of 72 988 specimens were tested, with 1 566 （2.14%） testing positive for HBoV. The lowest positivity rate was in 2024 （0.95%）, while the highest was in 2025 （4.09%）. Positivity rates were relatively high in autumn and winter, though peak seasons varied across years. The overall HBoV positivity rate was higher in male children （2.25%） than in female children （2.01%） （P=0.026）. The highest positivity rate was observed in the 1 to ＜2 years age group （5.42%）, while the lowest was found in the 6 to 17 years age group （0.38%）. Among HBoV-positive specimens, 813 cases （51.92%） were single infections, and 753 cases （48.08%） were co-infections. The top three non-bacterial respiratory pathogens associated with co-infections were human rhinovirus, respiratory syncytial virus and Mycoplasma pneumoniae.

CONCLUSIONS In hospitalized children in Ningbo, HBoV positivity is slightly higher in males than in females and peaks in the 1 to ＜2 years age group. Additionally, the autumn-winter season and co-infections with human rhinovirus, respiratory syncytial virus, and M. pneumoniae are significantly associated with the elevated positivity rates.