Antiviral Medication Update

As of September 12, 2009, 99% of circulating influenza viruses in the United States were 2009 H1N1 influenza which were susceptible to both Tamiflu and Relenza.¹ Appropriate use of antivirals for the treatment and prophylaxis is a crucial component to pandemic influenza prevention and control. In response to the current H1N1 and seasonal influenza concerns, Gateway Health Plan^® has added Tamiflu and Relenza to the Medicaid formulary and will continue to cover these medications for our Medicare Assured^® population. The Center for Disease Control (CDC) continues to update their recommendations for the use of antivirals in the treatment and prevention of influenza. Please take the following recommendations into consideration when determining if Tamiflu or Relenza is appropriate for your patients:

• Persons presenting with suspected influenza and more severe symptoms such as evidence of lower respiratory tract infection or clinical deterioration should receive prompt empiric antiviral therapy, regardless of previous health or age.
• People with more severe illness, such as those hospitalized with suspected or confirmed influenza
• Early empiric treatment with Tamiflu or Relenza should be considered for persons with suspected or confirmed influenza who are at higher risk for complications including:
  • Children younger than 2 years old;
  • Persons aged 65 years or older;
  • Pregnant women;
  • Persons of any age with certain chronic medical or immunosuppressive conditions and,
  • Persons younger than 19 years of age who are receiving long-term aspirin therapy.
• Individuals with mild illness who are not in the above high risk groups do not necessarily require antiviral treatment.
• Treatment, when indicated, should be initiated as early as possible because studies show that treatment initiated early (i.e., within 48 hours of illness onset) is more likely to provide benefit.
• Treatment should not wait for laboratory confirmation of influenza because laboratory testing can delay treatment and because a negative rapid test for influenza does not rule out influenza.
• Consideration for antiviral chemoprophylaxis should generally be reserved for persons at higher risk for influenza-related complications who have had contact with someone likely to have been infected with influenza. However, early treatment is an emphasized alternative to chemoprophylaxis after a suspected exposure. Household or close contacts (with risk factors for influenza complications) of confirmed or suspected cases can be counseled about the early signs and symptoms of influenza, and advised to immediately contact their health care provider for evaluation and possible early treatment if clinical signs or symptoms develop.

1. Updated Interim Recommendations for the Use of Antiviral Medications in the Treatment and Prevention of Influenza for the 2009-2010 Season. www.cdc.gov/H1N1flu/recommendations.htm. Accessed September 29, 2009.