2009 update in prevention, evaluation, and outpatient treatment of influenza

Background: Influenza A and B virus infections account for substantial morbidity and mortality and adversely affect quality of life and productivity in millions of Americans every year. Because of antigenic drifts and shifts, influenza is difficult to manage, presenting primary care clinicians with two major challenges every year: 'Who should be vaccinated?' and 'How should patients who present with symptoms of influenza be managed?' Methods: A search from 1995 to 2008 of the National Library of Medicine, the Cochrane Database of Systematic Reviews, the US Centers for Disease Control and Prevention (CDC) website, and the reference lists of retrieved articles was conducted to identify the most current and relevant information to address these two major challenges and the questions they generate in primary care. Emphasis was placed on influenza vaccination and antiviral agents. Findings: In all, 275 articles met the search criteria. Emphasis was placed on recommendations developed by the Advisory Committee on Immunization Practices for 2008-2009, as well as several advisories issued by the US Food and Drug Administration and the US CDC. Discussion: Eighty-five percent of the US population is eligible for influenza vaccination. Several measures have been demonstrated to improve vaccination rates. Diagnosis of influenza should be confirmed with testing such as a rapid viral test. Management of persons with influenza includes treatment with neuraminidase inhibitors and symptom-specific therapy. Conclusion: The implementation of more aggressive measures is needed in the primary care setting to prevent and treat influenza.