Perspective from Amesh A. Adalja, MD
July 29, 2019
2 min read

Prompt NAI treatment reduced hospital stays by 19% during last flu pandemic

Perspective from Amesh A. Adalja, MD
You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact

Neuraminidase inhibitor treatment initiated upon hospitalization decreased patients’ length of stay by 19% overall during the 2009-2010 influenza pandemic, according to findings from a meta-analysis published in The Journal of Infectious Diseases.

“The most pragmatic and important question is whether [neuraminidase inhibitor (NAI)] treatment, started on admission, irrespective of delay since symptom onset, reduces the [length of stay] in hospitalized patients with influenza,” Sudhir Venkatesan, PhD, MPH, research assistant in the University of Nottingham’s division of epidemiology and public health, and colleagues wrote. “Clinically, this is important because there can be significant uncertainty in ascertaining symptom onset, even by the attending physician.”

The meta-analysis included data on 18,309 patients infected with the pandemic influenza A(H1N1) virus from 70 clinical centers in 36 countries, and excluded patients with a length of stay less than 1 day and individuals who died while hospitalized.

The study results showed a 19% overall reduction in length of stay among patients who were promptly administered NAI treatment upon hospitalization compared with those who received it later or not at all (incidence rate ratio, 0.81; 95% CI, 0.78-0.85), with a median decrease of 1.19 days.

NAI treatment initiated less than 2 days after the onset of symptoms as well as NAI treatment administered at any time showed mixed patterns of association with a patient’s length of stay, the researchers reported. They observed an 8% decrease in length of stay in patients who were treated on the day of admission and not admitted to the ICU, and a 28% increase in promptly treated patients with chest radiography-confirmed influenza-related pneumonia.

Length of stay due to influenza can be influenced by a number of other factors, including complications stemming from the infection. According to the CDC, the 2017-2018 influenza season saw the highest spike in hospitalizations related to the virus since 2005 — with an estimated 959,000 patients admitted.

“Our data support current recommendations to treat adults hospitalized with clinically suspected influenza with NAIs as soon as possible upon admission,” the researchers wrote. “If used consistently, this strategy would contribute to the management of surge pressures and health care costs during seasonal influenza epidemics and pandemics.” – by Eamon Dreisbach


CDC. Estimated influenza illnesses, medical visits, hospitalizations, and deaths in the United States — 2017–2018 influenza season. Accessed July 25, 2019

Venkatesan S, et al. J Infect Dis. 2019;doi:10.1093/infdis/jiz152.

Disclosures: Venkatesan reports no relevant financial disclosures. Please see the full study for the other authors’ relevant financial disclosures.