Overview
Influenza is an acute respiratory tract infection that affects over one billion people globally each year. It spreads person-to-person via airborne droplets, contaminated hands, or objects 1.
Diagnosis
Reverse transcription polymerase chain reaction (RT-PCR), nucleic acid amplification tests (NAATs), and rapid tests are available for diagnosis 1.
Nasopharyngeal swabs may be preferred over midturbinate swabs for influenza diagnosis when a higher viral load is important, as midturbinate swabs yielded a 53% lower viral load in one study 2.Management
Antiviral and immunomodulatory drugs are available for treatment and prophylaxis 1.
For non-severe influenza, baloxavir is conditionally recommended if the risk of severe illness is high; antivirals are not recommended if the risk is low 1.
Oseltamivir is conditionally recommended for severe influenza 1.
Antibiotics are strongly recommended against if bacterial co-infection is unlikely 1.
Peramivir, zanamivir, macrolide antibiotics (in the absence of co-infection), mTOR inhibitors, plasma therapy, and corticosteroids are not recommended 1.Key Recommendations
For non-severe influenza, baloxavir is conditionally recommended if the risk of severe illness is high. (Evidence: Moderate)
Oseltamivir is conditionally recommended for severe influenza. (Evidence: Moderate)
Antibiotics are strongly recommended against if bacterial co-infection is unlikely. (Evidence: Strong)References
1 Meixner J, Nußbaumer-Streit B, Sommer I. [WHO clinical practice guidelines for influenza: an update]. Gesundheitswesen (Bundesverband der Arzte des Offentlichen Gesundheitsdienstes (Germany)) 2025. link
2 Bernasconi C, Katugampola L, Wildum S. Comparison of influenza viral load in nasopharyngeal and midturbinate swabs. Influenza and other respiratory viruses 2024. link