Influenza is generally a self-limited illness, but complications such as pneumonia, respiratory failure, and death can occur, especially in patients at higher risk for complications (see Table 1). Antiviral drugs recommended for treatment and chemoprophylaxis of influenza this season are listed in Table 2. Updated information on influenza activity and antiviral resistance is available from the CDC at www.cdc.gov/flu.

View the Comparison Chart: Antiviral Drugs for Influenza for 2021-2022

Influenza is generally a self-limited illness, but complications such as pneumonia, respiratory failure, and death can occur, especially in patients at increased risk for influenza complications (see Table 1). Antiviral drugs recommended for treatment and chemoprophylaxis of influenza this season are listed in Table 2. Updated information on influenza activity and antiviral resistance is available from the CDC at www.cdc.gov/flu.

Annual vaccination against influenza A and B viruses is recommended for everyone ≥6 months old without a contraindication. Available vaccines and recommendations for specific patient populations for the 2019-2020 season are listed in Tables 2 and 3.

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.

Antiviral drugs can be used for treatment and prophylaxis of influenza. Frequently updated information on influenza activity, testing for influenza, and antiviral resistance is available from the CDC at www.cdc.gov/flu.

Antiviral drugs can be used for prophylaxis and treatment of influenza. Frequently updated information on influenza activity, testing for influenza, and antiviral resistance is available from the CDC at www.cdc.gov/flu.

Antiviral drugs can be used for treatment of influenza and as an adjunct to influenza vaccination1 for prophylaxis. Frequently updated information on influenza activity and antiviral resistance is available from the CDC at www.cdc.gov/flu.

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 (Relenza), which is inhaled, are approved for prophylaxis and treatment of influenza in children and adults.

Some readers of our article on Antiviral Drugs for Seasonal Influenza have expressed concerns regarding our recommendation for use of the oral neuraminidase inhibitor oseltamivir (Tamiflu) to treat high-risk patients with confirmed or suspected influenza illness, citing the British Medical Journal and The Cochrane Collaboration, which have contended that there is no acceptable evidence that the drug prevents complications or hospitalizations and have questioned the completeness of the results of controlled trials conducted by the manufacturer (Roche).

Antiviral drugs can be used for treatment of influenza and as an adjunct to influenza vaccination for prophylaxis. Frequently updated information on influenza activity and antiviral resistance is available from the CDC at www.cdc.gov/flu.

Antiviral drugs can be used for treatment of influenza and as an adjunct to influenza vaccination for prophylaxis. Frequently updated information on antiviral resistance is available at www.cdc.gov.

Antiviral drugs can be used as an adjunct to vaccination for prophylaxis and treatment of influenza. In recent years, the susceptibility of circulating influenza virus strains has evolved rapidly and treatment recommendations have changed during the influenza season. Frequently updated information on antiviral resistance is available at www.cdc.gov/flu/professionals/antivirals.

Antiviral drugs can be used for treatment and prophylaxis of influenza. In recent years, the susceptibility of circulating influenza strains has evolved rapidly and treatment recommendations have changed during the influenza season. The CDC influenza website provides frequently updated information on antiviral resistance (www.cdc.gov/flu).

Antiviral drugs can be used for treatment of patients with influenza and for prophylaxis when exposure to the disease occurs before or less than 2 weeks after vaccination. They can also be used to control institutional outbreaks of influenza. In recent years, the susceptibility of circulating influenza strains has evolved rapidly and treatment recommendations have changed during the influenza season. The CDC influenza web site provides frequently updated information on antiviral resistance (www.cdc.gov/flu)

Currently circulating influenza virus is almost universally pandemic 2009 influenza A H1N1, but seasonal influenza strains could also appear soon. Antiviral drugs are an important adjunct to influenza vaccination for treatment and chemoprophylaxis of both pandemic and seasonal influenza. They may, however, interfere with the efficacy of FluMist, the live-attenuated intranasal vaccine, if they are administered within 48 hours before or <2 weeks after FluMist administration. Inactivated vaccines are not affected by antiviral drug therapy.

Antiviral drugs are an important adjunct to influenza vaccination and can be used for treatment of patients with influenza within 2 days of the onset of illness and for chemoprophylaxis of influenza exposures that occur before or less than 2 weeks after vaccination. Patients who are immunocompromised or immunosuppressed, have pulmonary disease, are elderly or are healthcare workers may also be appropriate candidates for chemoprophylaxis.

Antiviral drugs can be used for treatment of patients with influenza and for prophylaxis of influenza exposures that occur before or less than 2 weeks after vaccination. They can also be used to control institutional influenza outbreaks and for prophylaxis in years when circulating strains differ from those included in the vaccine.

Antiviral drugs can be used to control institutional influenza outbreaks and for prophylaxis of influenza exposures that occur before or less than 2 weeks after vaccination with inactivated vaccine, or in years when circulating strains differ from those included in the vaccine. They can also be used for early treatment of patients with influenza.

Antiviral prophylaxis is indicated for influenza exposures that occur before (or less than 2 weeks after) vaccination with inactivated vaccine, or in years when circulating strains differ from those included in the vaccine. Antiviral drugs can also be used for treatment of patients who develop symptoms of influenza, regardless of vaccination status.
Please see Update: Influenza Resistance to Amantadine and Rimantadine

Unlike the last few years there is no early-season shortage of influenza vaccine. Immunization programs for all recommended individuals can proceed. There are 2 new influenza vaccine formulations available this year, FluMist, an intranasal vaccine and Fluzone, a pediatric formulation. Timing, indications, adverse effects, dosage and cost of the vaccines is discussed. The drugs that can be used for prophylaxis of influenza are also reviewed.

Influenza vaccine for the 2002-2003 season will include last year's A strains, A/New Caledonia/20/99 (H1N1)-like and A/Moscow/10/99 (H3N2)-like, and a new B strain, B/Hong-Kong/330/01-like (MMWR Morb Mortal Wkly Rep 2002; 51:503).