Developments in Influenza Prevention and Treatment

Abstract

Until recently, control of influenza has focused on increasing the use of the inactivated influenza vaccine and, in some countries, encouraging the appropriate use of the antiviral drugs amantadine and rimantadine. Now that a new class of antiviral drugs, the neuraminidase inhibitors, has been approved for use in many countries, and a live attenuated vaccine is on the horizon, novel opportunities have arisen for the prevention and treatment of influenza. The clinical effectiveness of these innovations has not been fully determined in many patient populations, particularly in managed-care environments; clinical and economic impacts are similarly considered in making decisions regarding access to new technologies in most healthcare delivery systems. However, it is possible to use available information to speculate on how these technologies might be used, while the relative clinical and cost consequences of these innovations are further clarified.

In treatment, the neuraminidase inhibitors have been shown to significantly reduce the duration of influenza-related illness and usage of antibacterial drugs. As the clinical benefits and cost effectiveness of new drugs are documented, utilisation of these agents is likely to extend from those with underlying risk conditions to previously healthy individuals. For prevention, the new live attenuated vaccines will be increasingly used in children. Inactivated vaccines will continue to be used mainly for the elderly and adults with underlying health conditions. There will also be a limited role for the antiviral drugs in prophylaxis seasonally, but more extensive use is likely in families and in the workplace for short periods after exposure. Relative differences in clinical effectiveness, patient preference and cost will inform managed-care organisations on whether to promote or restrict the use of these interventions in various patient populations.