Contact Us
- 800–CDC–INFO
- (800-232-4636)
- 888–232–6348 (TTY)
- cdcinfo@cdc.gov
Indications for Use of Antiviral Agents for Seasonal Influenza (Treatment and Prevention)
NOTE: This information is taken from “Prevention and Control of Influenza Recommendations of the Advisory Committee on Immunization Practices (ACIP), 2007” (MMWR 2007 Jul 13:5[RR06];1-54) and focuses on the two licensed influenza antiviral agents recommended for use in the United States during the 2007-08 influenza season: oseltamivir and zanamivir.
On this page:
Treatment
Oseltamivir and zanamivir can reduce the duration of uncomplicated influenza A and B illness by approximately 1 day. Limited data suggest oseltamivir and zanamivir may also prevent serious influenza-related complications (e.g., bacterial or viral pneumonia or exacerbation of chronic diseases) in uncomplicated influenza. Evidence for the effectiveness of oseltamivir and zanamivir for treatment of influenza among persons who have been hospitalized because of influenza complications is limited.
The recommended duration of treatment with oseltamivir and zanamivir is 5 days.
Prevention
The use of influenza antiviral medications is not a substitute for vaccination, but it is a critical adjunct in preventing and controlling influenza. Community studies of healthy adults indicate that oseltamivir and zanamivir are similarly effective in preventing febrile, laboratory-confirmed influenza illness (efficacy: zanamivir, 84%; oseltamivir, 82%). Both medications also have been reported to prevent influenza illness among persons with an ill household member diagnosed with influenza. In institutional settings, one 6-week study of oseltamivir prophylaxis among nursing home residents reported a 92% reduction in influenza illness.
When determining the timing and duration for administering oseltamivir or zanamivir for prevention, factors related to cost, compliance, and potential side effects should be considered. To be maximally effective as prophylaxis, the drug must be taken each day for the duration of influenza activity in the community.
Consider Use of the Neuraminidase Inhibitors in These People:
People at High Risk Who Are Vaccinated After Influenza Activity Has Begun
People at high risk for complications of influenza should still be vaccinated even if an outbreak of influenza has already begun. However, development of antibodies in adults after vaccination takes approximately 2 weeks and can take longer in children depending on their age and vaccination status. When influenza vaccine is administered while influenza viruses are circulating, antiviral medications for prevention can be considered for persons at high risk during the time from vaccination until immunity after vaccination typically will have developed (two weeks).
People Who Provide Care to Those at High Risk
To reduce the spread of virus to persons at high risk during community or institutional outbreaks, chemoprophylaxis during peak influenza activity can be considered for unvaccinated persons who have frequent contact with persons at high risk. These persons should receive vaccination with the trivalent inactivated influenza vaccine (TIV) also. Persons with frequent contact include employees of hospitals, clinics, and chronic-care facilities, household members, visiting nurses, and volunteer workers. If an outbreak is caused by a variant strain of influenza that might not be controlled by the vaccine, chemoprophylaxis should be considered for all such persons, regardless of their vaccination status. Use of live attenuated influenza vaccine) LAIV while receiving antiviral medications is not recommended.
People Who Have Immune Deficiencies
Chemoprophylaxis can be considered for persons at high risk who are expected to have an inadequate antibody response to influenza vaccine. This category includes persons infected with HIV, chiefly those with advanced HIV disease. No published data are available concerning possible efficacy of chemoprophylaxis among persons with HIV infection or interactions with other drugs used to manage HIV infection. Such patients should be monitored closely if chemoprophylaxis is administered.
Other People
Chemoprophylaxis throughout the influenza season or during peak influenza activity might be appropriate for people at high risk who should not be vaccinated. Chemoprophylaxis can also be offered to persons who wish to avoid influenza illness and for who cannot receive influenza vaccination. Health-care providers and patients should make this decision on an individual basis.
- Page last updated September 26, 2007
- Content Source: Coordinating Center for Infectious Diseases (CCID)
- National Center for Immunization and Respiratory Diseases (NCIRD)
