#19,287
While the timing and severity of the next flu season is uncertain, we are already seeing reports of increased flu activity in Asia (see HK DH investigates case of severe paediatric influenza A infection), making the following JAMA Pediatrics study on the effectiveness of Oseltamivir in hospitalized children both timely and reassuring.
One of the popular memes on the internet and in tabloid media has been that the influenza antiviral drug oseltamivir (Tamiflu ®) is either A) Ineffective or B) Ineffective and Dangerous.
A cherry picking of data, along with hyperbolic media reports – like the Daily Mail’s Ministers blew £650MILLION on useless anti-flu drugs - have helped to drive these beliefs.
Admittedly, antivirals are not a panacea against influenza infection, but when administered early in an infection, they can significantly reduce the severity and duration of illness.
The addition of an FDA warning in 2008 - based on primarily on media reports from Japan - warning of rare `Neuropsychiatric events' (particularly among pediatric patients), further drove public opinion.
A 2018 report, however (see Study Finds No Relationship Between Suicide & Oseltamivir In Pediatric Patients), strongly refuted those claims, but the stigma remains.
As a result, oseltamivir is often underused, even though we've seen repeated studies showing their worth (see CID Journal: Under Utilization Of Antivirals For At Risk Flu Patients and CDC Study: Early flu Antiviral Treatment Can Shorten Hospital Stays in Children With Flu).
All of which brings us to a new investigative report, published yesterday in JAMA Pediatrics, which finds that oseltamivir treatment was associated with a 31% lower hazard of ICU admission and shortened hospital LOS (Length of stay) in hospitalized pediatric patients with lab confirmed influenza.
Due to its length, I've only reproduced the summary, abstract, and a few excerpts. Follow the link to read it in its entirety.
Original Investigation
Effectiveness of Oseltamivir in Hospitalized Children With Laboratory-Confirmed Influenza, 2014-2023
Kacie Rytlewski, MD1; Angela Dunn, MS2; Alissa O’Halloran, MSPH3 et al
Published Online: August 10, 2026
doi: 10.1001/jamapediatrics.2026.3376Key Points
Question Does oseltamivir treatment reduce risk of intensive care unit (ICU) admission and hospital length of stay among pediatric patients hospitalized with influenza?
Findings Using a cohort study from a population-based surveillance network in 13 states across 8 influenza seasons, oseltamivir treatment was found to decrease both the likelihood of ICU admission and hospital length of stay among pediatric patients hospitalized with laboratory-confirmed influenza.
Meaning These findings support the current national recommendations from the American Academy of Pediatrics, US Centers for Disease Control and Prevention, and Infectious Diseases Society of America that recommend antiviral treatment for children hospitalized with laboratory-confirmed influenza.
Abstract
Importance National organizations recommend antiviral treatment for hospitalized children with influenza; however, use in this setting has recently declined. Studies of oseltamivir effectiveness in children are limited by misclassification bias, unknown symptom onset date, and incomplete capture of antiviral use prior to admission.
Objective To assess the association between oseltamivir receipt and intensive care unit (ICU) admission and hospital length of stay (LOS) among pediatric influenza-associated hospitalizations.
Design, Setting, and Participants This cohort study used data that were obtained from the Influenza Hospitalization Surveillance Network (FluSurv-NET), which conducts US population-based surveillance for laboratory-confirmed influenza hospitalizations for all ages across 13 states. The study data include seasons 2014 to 2015 through 2022 to 2023, excluding 2020 to 2021. Participants included children aged younger than 18 years who were hospitalized with laboratory-confirmed influenza and for whom a respiratory symptom onset date was available. These data were analyzed from October 2024 through May 2026.
Exposures Oseltamivir receipt as a time-dependent exposure.
Main Outcome(s) and Measure(s) The primary outcome was time from symptom onset to ICU admission. Secondary outcome was time from admission to discharge (LOS). Adjusted Cox proportional hazard models (aHR) with oseltamivir receipt as a time-dependent exposure were used.
Results After exclusions, 6044 influenza cases were included in the primary ICU analysis, of whom 4240 (70.2%) received oseltamivir, and 7103 cases were included in the secondary LOS analysis, of whom 5746 (80.9%) received oseltamivir. In the ICU analysis, the median (IQR) age was 3 (1-7) years, 3382 (56%) were male and 3721 (44%) were female, and 2937 (49%) had 1 or more medical comorbidity—the most common of which was asthma in 1547 children (26%). In adjusted models, compared with untreated children, oseltamivir treatment reduced the hazard of ICU admission (aHR, 0.69; 95% CI, 0.60-0.80) and shortened LOS (analyzed as hazard of hospital discharge; aHR, 1.13; 95% CI, 1.06-1.21).
Conclusions and Relevance In this cohort of children hospitalized with influenza, oseltamivir treatment was significantly associated with a reduced risk of ICU admission by 31% and decreased hospital LOS. These findings demonstrate the benefits of oseltamivir receipt and support current national recommendations for oseltamivir treatment as soon as possible in children hospitalized with suspected or laboratory-confirmed influenza.
(SNIP)
Our main finding was a significant decrease in ICU admission risk among hospitalized children with laboratory-confirmed influenza treated with oseltamivir compared with those not treated. The association persisted after excluding patients who received oseltamivir prior to admission. The association of oseltamivir with decreased odds of ICU admission has been shown in prior retrospective cohort studies in children.7 Importantly, our additional analyses of age, underlying medical comorbidity, and timing of oseltamivir initiation from symptom onset showed consistent benefit for all hospitalized pediatric patients with influenza.
Our analyses also demonstrated a significant decrease in the hospital LOS among those receiving oseltamivir, reflected as an increased hazard of discharge; this is notable particularly given that cases had a relatively short LOS (median, 3 days). This finding persisted in our sensitivity analyses. There was no evidence of effect modification by age or medical comorbidity. We observed the reduction in LOS most prominently with early treatment, which has been observed previously.5,7 Our findings suggest that health care professionals should encourage caregivers of children to seek care early in the course of influenza-like illness and also urgently consider oseltamivir treatment for all children and adolescents hospitalized with suspected or confirmed influenza.
