Association Between Oseltamivir Timing and Clinical Outcomes in Hospitalized Children with Influenza: A Retrospective Cohort Study.

BACKGROUND

Influenza is one of the most common viruses causing an acute course illness, mainly targeting the respiratory system. It is a communicable disease that spreads easily between individuals and is usually self-limiting in most cases. However, complications of influenza are numerous, including secondary bacterial infections, exacerbation of underlying respiratory conditions, and central nervous system-related complications. The risk of influenza-related hospitalization and complications is increased in children younger than 5 years and in those with underlying chronic diseases. Three classes of antiviral therapy are used in the treatment of influenza: neuraminidase inhibitors, adamantanes, and inhibitors of influenza cap-dependent endonuclease. Oseltamivir is considered the mainstay therapy for influenza treatment.

OBJECTIVE

This study investigates the efficacy of early oseltamivir treatment compared to late treatment in improving recovery by reducing hospital length of stay and preventing influenza-related complications such as pneumonia, otitis media, and asthma exacerbations.

METHODOLOGY: This retrospective study analyzed data from 280 pediatric patients admitted to a tertiary care hospital between January 2020 and April 2023. Included patients were aged 1 month to 14 years, had laboratory-confirmed influenza A or B by polymerase chain reaction or point-of-care rapid testing, and received oseltamivir during hospitalization. Early oseltamivir treatment was defined as initiation within 48 hours of symptom onset, whereas initiation after 48 hours was considered late.

RESULTS

The study included 151 (53.9%) males and 129 (46.1%) females. Children who received early oseltamivir treatment had a significantly shorter hospital length of stay of approximately one day (∼16-19 hours) compared to those who started treatment after 48 hours [mean ± SD: 3.28 ± 1.46 vs 3.95 ± 2.26 days; P = 0.007]. A weak positive correlation was observed between time to oseltamivir initiation and hospital length of stay (r = 0.13, P = 0.02). Early treatment was associated with a significantly lower incidence of pneumonia, otitis media, and acute asthma exacerbation compared to late treatment (P < 0.05 for all).

CONCLUSION

Early initiation of oseltamivir within 48 hours is effective in reducing hospital length of stay and preventing common influenza-related complications.