Influenza.

Influenza is the most frequent cause of acute respiratory illness requiring medical intervention because it affects all age groups and because it can recur in any individual. During the past three decades, efforts to prevent and control influenza have focused primarily on the use of inactivated influenza vaccines in elderly people and in individuals with chronic medical conditions that put them at risk for complications. However, the continuing impact of influenza in these and other population groups has motivated the development of novel approaches for prevention and control of influenza. Several important advances in the field of influenza have occurred in the last few years. An experimental live, attenuated, intranasally administered trivalent influenza vaccine was shown to be highly effective in protecting young children against influenza A H3N2 and influenza B. New antiviral drugs based on the structure of the neuraminidase molecule were assessed in clinical trials and found to be effective against influenza A and B viruses. The expected use of these new antiviral agents has accelerated the development of rapid point-of-care diagnostic tests. The availability of new diagnostic tests, new antiviral drugs, and new vaccines will undoubtedly alter our approaches to influenza control and have an impact on clinical practice.