FluMist (MedImmune), the first live-attenuated and first intranasally administered influenza vaccine, has been approved by the FDA to prevent influenza in healthy people 5-49 years old. Given as a nasal spray, it stimulates immunity by viral replication in the upper respiratory tract. This vaccine apparently will be advertised directly to the public as a "needle-free" alternative to intramuscular influenza vaccine.

Addendum: FluMist Storage: The storage requirements for FluMist, the intranasal live-attenuated influenza vaccine (Medical Letter 2003; 45:65) have changed. New data have shown that frost-free freezers are appropriate for storage for at least 3 months, without need for a freezer-box insert.

Two new trivalent influenza vaccines, Flucelvax (Novartis) and Flublok (Protein Sciences), will soon be available for prevention of seasonal influenza in adults ≥18 years old (Flucelvax) and 18-49 years old (Flublok). Unlike other available influenza vaccines, neither vaccine is produced in eggs, removing any concern regarding use in egg-allergic patients. Avoiding the use of eggs should allow for faster production of these 2 new vaccines, which could be especially beneficial during a pandemic.Flucelvax is prepared in a similar manner to other influenza vaccines, but the influenza virus is...

Annual vaccination against influenza A and B viruses is recommended in the US for everyone ≥6 months old without a contraindication. Influenza vaccines available in the US for the 2025-2026 season are listed in Table 2.

The FDA has licensed 4 new monovalent vaccines for prevention of respiratory illness caused by a new influenza A H1N1 virus that appears to be derived from a swine strain. The 5th vaccine should be licensed soon. All of these vaccines are expected to become available in October. An intranasal formulation is expected in the first week of October.

The FDA has approved peramivir (Rapivab – BioCryst), an IV neuraminidase inhibitor administered as a single dose, for treatment of acute uncomplicated influenza in patients ≥18 years old who have had symptoms for no more than 2 days. Peramivir was available temporarily in the US during the 2009-2010 influenza season under an emergency use authorization for treatment of hospitalized patients. It has been available in some Asian countries since 2010. Peramivir is the third neuraminidase inhibitor to be approved in the US. Oseltamivir (Tamiflu), which is taken orally, and zanamivir...

Influenza is generally a self-limited illness, but complications including pneumonia, respiratory failure, and death can occur, especially in persons at increased risk (see Table 1).

The FDA has issued an Emergency Use Authorization (EUA) for the long-acting investigational IV monoclonal antibody pemivibart (Pemgarda – Invivyd) for pre-exposure prophylaxis of COVID-19 in persons ≥12 years old (weight ≥40 kg) who have moderate to severe immune compromise and are unlikely to respond adequately to COVID-19 vaccination (see Table 1). Pemgarda is the only drug that is currently authorized in the US for pre-exposure prophylaxis of COVID-19. Tixagevimab/cilgavimab (Evusheld) was previously available under an EUA for this indication, but it lacks activity against...

View the Comparison Table: Antiviral Drugs for Seasonal Influenza for 2025-2026

The FDA has approved baloxavir marboxil (Xofluza – Shionogi/Genentech), the first polymerase acidic (PA) endonuclease inhibitor, for single-dose, oral treatment of acute uncomplicated influenza in patients ≥12 years old. Baloxavir is the first drug with a new mechanism of action to be approved for treatment of influenza in almost 20 years.