This is a multicenter, randomized, positive-controlled, non-inferiority clinical study, planning to enroll 90 children with bronchiolitis caused by respiratory syncytial virus infection, to evaluate the safety and efficacy of inhaled Peginterferon α-2b injection compared to recombinant human interferon α2b in the treatment of pediatric respiratory syncytial virus bronchiolitis.

Inclusion Criteria:

1. The guardian of the child is able to understand the content, requirements, and limitations of the protocol, fully understands the possible adverse reactions that may occur during the study, is willing to complete the follow-up as required, and voluntarily signs the informed consent form before the start of the study.
2. The child's age is 6 months or older but no more than 2 years old (including the critical value) at the time of signing the informed consent, and the gender is not specified.
3. Positive viral detection in nasopharyngeal swab.
4. Presence of rapid breathing, wheezing, moist rales and/or wheezing sounds in the lungs; with or without chest imaging showing signs of hyperinflation, patchy infiltrates, localized atelectasis, and peribronchitis.
5. The severity of the illness is mild or moderate (evaluation criteria see Appendix 1: Wang Bronchiolitis Scoring Standard).
6. The time from the onset of the child's illness to the signing of the informed consent form is within 72 hours (the appearance of symptoms and signs related to RSV bronchiolitis does not exceed 72 hours from the signing of the informed consent, including but not limited to: tachypnea, wheezing, hypoxemia, dyspnea, fever).
7. No use of other antiviral drugs or immunomodulators within 3 weeks before randomization.

Exclusion Criteria:

1. Extreme restlessness, drowsiness, coma, and possibly requiring mechanical ventilation assistance for breathing.
2. Presence of other chronic severe diseases such as cardiac insufficiency, respiratory insufficiency, liver insufficiency, renal insufficiency, and severe malnutrition.
3. Having autoimmune diseases such as systemic lupus erythematosus or psoriasis, or immunodeficiency diseases.
4. Having epilepsy or other disorders of central nervous system function.
5. The investigator's comprehensive judgment suspects a concurrent bacterial infection.
6. Clinical diagnosis of myocarditis or suspected myocarditis (diagnostic criteria see Appendix 2: Diagnostic Recommendations for Myocarditis in Children).
7. Known or suspected allergy to interferon or excipients.
8. Participation in other interventional clinical trials within 3 months prior to screening, or planning to participate in other clinical trials during the study period. (9) A history of pneumonia in the past 3 months.

(10) Other conditions deemed unsuitable for inclusion by the investigator.