[Respiratory viruses: epidemiologic features, clinical impact, and management]

Respiratory viral infections are the most frequent cause for morbidity in humans. Among the different etiological agents, influenza virus causes a disproportionate fraction of morbidity and mortality among the elderly and patients with chronic conditions, who have been traditionally the target of the bulk of preventive measures. Recent epidemiological studies though have demonstrated an important role for influenza viruses to cause morbidity among infants. Conversely, Respiratory Syncytial Virus appears also capable to cause substantial morbidity in adults. Influenza prevention and treatment requires the integrated use of vaccines and of antivirals, including the new neuraminidase inhibitors, either as chemoprophylactic or as chemotherapeutic agents. The implementation of current guidelines is a challenge for all the health care workers involved, even though their cost effectiveness is well demonstrated. In addition, considering the recent epidemiological data, should these guidelines be amended to include young children in groups to be vaccinated?