Factors associated with non-prescription of oseltamivir for infant influenza over nine seasons.

ABSTRACT

BACKGROUND/OBJECTIVE: The Centers for Disease Control and Prevention (CDC) recommends oseltamivir phosphate for children <2 years old with confirmed or suspected influenza as they are at high risk for complications. We analyzed infant characteristics associated with non-prescription of oseltamivir over nine years. METHODS: We conducted a retrospective electronic health record (EHR) review of infants <12 months old born between January 1, 2012 and December 31, 2019 within the UPMC health system in Southwestern Pennsylvania who had >2 well-child visits during their first year. Infants with a confirmed positive test for influenza were included in the analysis. Factors associated with infant oseltamivir non-prescription were assessed using multivariable logistic regression. RESULTS: Of 457 infants with confirmed influenza, 86% were prescribed oseltamivir. The proportion of infants prescribed oseltamivir increased from an average of 64.6% during 2012-2016 influenza seasons to 90.4% during 2016-2020 influenza seasons. Infants were more likely to not be prescribed oseltamivir if they experienced >2 days of influenza symptoms (OR 9.4, 95% CI 4.8, 18.7, P< 0.001), were diagnosed during the 2012-2016 influenza seasons (OR 4.2, 95% CI 1.8, 9.5, P<0.001), tested positive for influenza via a multiplex/RT-PCR test (OR 6.7, 95% CI 2.7, 16.3, P<0.001; OR 2.7, 95% CI 1.1, 7.1; P=0.04), or did not have a fever at point-of-care (OR 2.3, 95% CI 1.2, 4.6, P=0.01). CONCLUSION: Adherence to CDC influenza antiviral treatment guidelines for infants is high and improved over time. However, provision of targeted education to providers may further improve oseltamivir prescribing practices for high-risk children <12 months of age.